The tag goes at the top of the card, where it gets looked at

Label chips sat under the body, the checklist, the attachments and the link
previews. On a tall note that puts the one thing saying what a note IS below
the fold of a glance — and a board is scanned, not read. "Which of these is
about the thing I am looking for" should be the first thing the eye lands on.

Above the body rather than beside it: the body's first line is the note's
NAME (M13 steps 3 and 4), and a chip floated next to it would compete with
the thing that identifies the note. A row of its own costs one line, and only
on notes that carry tags.

Both surfaces, same order. Does not depend on tag lifting, which is a much
larger change — see the task.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

.forgejo/workflows/ci.yml

@@ -193,8 +193,7 @@ jobs:
   # them ever executed by CI — and the schema the migrations build had never been
   # checked against the models that read it.
   #
-  # Runs for visibility and does NOT gate the build, matching the `test` lane and
-  # FabledScribe's equivalent job.
+  # Gates the build, along with every other lane — see the `build` job's `needs`.
   #
   # Job key stays separator-free ("integration") with no `name:` — rule 80. act_runner
   # derives the service-container name from the truncated job display name, and the
@@ -261,10 +260,16 @@ jobs:
 
   build:
     name: Build & push image
-    # Build gates on lint + typecheck. The `test` job runs in parallel for
-    # visibility but does not block dev image builds (DB-backed integration
-    # testing happens against the dev image manually, not on every push).
-    needs: [gate, typecheck, lint]
+    # Every lane gates the build. This once stopped at lint + typecheck, on the
+    # reasoning that DB-backed testing happened manually against the dev image
+    # rather than on every push — true until 6f21db8 added the integration lane,
+    # and false since.
+    #
+    # What that gap cost: run 4293 failed `test` and published :dev and :<sha>
+    # anyway, so the deployed server ran a build whose test lane was red. An image
+    # tag is the rollback substrate (family rule 46); one that can be published
+    # from a failing run is not a substrate you can roll back TO.
+    needs: [gate, typecheck, lint, test, integration]
     if: needs.gate.outputs.build == 'true'
     runs-on: python-ci
     container:

alembic/versions/0027_checklist_items_into_body.py

@@ -0,0 +1,128 @@
+"""fold note_items into the note body and drop the table
+
+Revision ID: 0027
+Revises: 0026
+Create Date: 2026-08-24
+
+M304. A checklist item becomes a `- [ ] milk` line of `notes.body`, and `note_items`
+goes. The reason is positional, not cosmetic: a row had a position in a table and no
+position in the text, so a separate list could only ever render AFTER the prose. With
+the items in the body, a list can sit between two paragraphs — which is the thing that
+could not be built before and no amount of restyling would have delivered.
+
+## This migration rewrites note bodies
+
+Every note that has items gets its body appended to. The rules below are strict
+because rewriting somebody's text deserves it — not, as an earlier draft of this
+docstring claimed, because this instance holds imported Google Keep notes. It does
+not; note 2916's headline is that nothing here is anyone's work but the operator's
+test data. What 2916 actually says about imports is conditional — text arriving from
+another app WOULD be real, and any import path has to treat it that way — and the
+importer this migration shares a format with is one nobody here has run.
+
+Careful was still the right call. It cost little, and the same care is what the rule
+demands the day someone does import something:
+
+  * Rows are read BEFORE the table is dropped, in this one transaction.
+  * The existing body is never rewritten, only appended to.
+  * The layout — a blank line between prose and the list, nothing between consecutive
+    items — is byte-for-byte what `_note_markdown` has always exported and what
+    `derive::append_item` produces on every client. All three landing on the same text
+    is what lets the clients migrate their own SQLite stores independently and still
+    agree with the server, with no sync required to reconcile them.
+
+## The fold is inlined on purpose
+
+`notes/checklist.py` has this same function and this migration deliberately does not
+import it. A migration has to keep producing what it produced the day it ran; if the
+app's spacing rule ever changes, this file must not change with it.
+
+## `updated_at` is left alone, and that is load-bearing
+
+Raw SQL, so SQLAlchemy's `onupdate` never fires. Two reasons, and the second matters
+more than the first. Every client folds the same rows the same way, so the new body is
+news to nobody. And a client holding an UNPUSHED body edit still has the newer
+`updated_at`, so when it pulls the migrated note last-write-wins keeps its edit instead
+of the migration silently winning.
+
+The `notes` row's own `sync_revision` trigger (migration 0015) does fire, so every
+migrated note becomes pullable once. That is wanted: it is what makes a client whose
+local fold somehow differed converge on the server's text.
+
+## The downgrade is not a true inverse, and says so
+
+It recreates an empty `note_items` and leaves the bodies alone. Nothing is lost —
+every item is still there as text, which is where this migration put it — but the old
+code would show those notes as prose with no checklist. A faithful inverse is not
+possible: once the items are lines, nothing distinguishes a line this migration wrote
+from one somebody typed, and a downgrade that guessed would eat hand-written task
+lists. The real rollback is a database restore.
+
+Recreating the table is not decoration, though. Migration 0015's downgrade runs
+`DROP TRIGGER IF EXISTS trg_note_items_bump_note ON note_items`, and `IF EXISTS`
+covers the trigger, not the table — against a missing table that statement errors. So
+this is what keeps the migration chain runnable all the way back down.
+"""
+import re
+
+import sqlalchemy as sa
+from alembic import op
+from sqlalchemy.dialects.postgresql import UUID
+
+revision = "0027"
+down_revision = "0026"
+branch_labels = None
+depends_on = None
+
+_TASK_RE = re.compile(r"^\s*[-*] +\[[ xX]\](?: +.*)?$")
+
+
+def _append_item(body: str, text: str, checked: bool) -> str:
+    mark = "x" if checked else " "
+    text = (text or "").strip()
+    line = f"- [{mark}] {text}" if text else f"- [{mark}]"
+    trimmed = (body or "").rstrip("\n")
+    if not trimmed.strip():
+        return line
+    follows_a_list = bool(_TASK_RE.match(trimmed.split("\n")[-1]))
+    return f"{trimmed}\n{line}" if follows_a_list else f"{trimmed}\n\n{line}"
+
+
+def upgrade():
+    bind = op.get_bind()
+    rows = bind.execute(
+        sa.text("SELECT note_id, text, checked FROM note_items ORDER BY note_id, position, created_at")
+    ).fetchall()
+
+    grouped: dict = {}
+    for note_id, text, checked in rows:
+        grouped.setdefault(note_id, []).append((text, bool(checked)))
+
+    for note_id, items in grouped.items():
+        body = bind.execute(sa.text("SELECT body FROM notes WHERE id = :id"), {"id": note_id}).scalar()
+        # An item whose note is already gone has nothing to fold into. The foreign key
+        # should make this impossible; skipping costs nothing and failing here would
+        # leave the database half-migrated.
+        if body is None:
+            continue
+        for text, checked in items:
+            body = _append_item(body, text, checked)
+        bind.execute(sa.text("UPDATE notes SET body = :body WHERE id = :id"), {"body": body, "id": note_id})
+
+    op.drop_table("note_items")
+
+
+def downgrade():
+    # Column-for-column as migration 0006 created it, index name included: 0015's
+    # downgrade names both the table and its trigger, so a near-enough copy is not
+    # good enough.
+    op.create_table(
+        "note_items",
+        sa.Column("id", UUID(as_uuid=True), primary_key=True),
+        sa.Column("note_id", UUID(as_uuid=True), sa.ForeignKey("notes.id", ondelete="CASCADE"), nullable=False),
+        sa.Column("text", sa.Text(), nullable=False),
+        sa.Column("checked", sa.Boolean(), nullable=False, server_default=sa.false()),
+        sa.Column("position", sa.Integer(), nullable=False, server_default="0"),
+        sa.Column("created_at", sa.DateTime(timezone=True), nullable=False, server_default=sa.func.now()),
+    )
+    op.create_index("ix_note_items_note", "note_items", ["note_id"])

android/app/src/main/AndroidManifest.xml

@@ -7,6 +7,9 @@
       this permission never exercised.
     -->
     <uses-permission android:name="android.permission.INTERNET" />
+    <!-- Only to answer "is this connection metered?" before the app downloads its own
+         update in the background. Normal permission, no prompt, no location. -->
+    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
 
     <!--
       Four more permissions are NOT declared here and still reach the merged

android/app/src/main/java/com/fabledsword/thoughtsync/AppUpdate.kt

@@ -4,6 +4,8 @@ import android.content.Context
 import android.content.Intent
 import android.content.IntentSender
 import android.content.pm.PackageInstaller
+import android.net.ConnectivityManager
+import android.net.NetworkCapabilities
 import android.net.Uri
 import android.os.Build
 import android.provider.Settings
@@ -62,6 +64,30 @@ object AppUpdate {
             .setData(Uri.fromParts("package", context.packageName, null))
             .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
 
+    /**
+     * Whether this is wifi somebody is not paying by the megabyte for.
+     *
+     * The app fetches its own update in the background, and fifty-odd megabytes over
+     * mobile data is a bill nobody agreed to. Anywhere else it simply waits — the
+     * update is found, nothing is downloaded, and nothing is said until it can be.
+     *
+     * BOTH conditions, deliberately. Wifi alone would still download over a tethered
+     * hotspot, which is mobile data wearing a different hat and the exact bill this
+     * avoids. Unmetered alone would download over an unmetered cellular plan, which
+     * is not what "on wifi" means to the person who asked for it.
+     *
+     * Every uncertain answer is `false`: the cautious one costs nothing.
+     */
+    fun onWifi(context: Context): Boolean {
+        val caps =
+            context
+                .getSystemService(ConnectivityManager::class.java)
+                ?.let { manager -> manager.activeNetwork?.let(manager::getNetworkCapabilities) }
+        return caps != null &&
+            caps.hasTransport(NetworkCapabilities.TRANSPORT_WIFI) &&
+            caps.hasCapability(NetworkCapabilities.NET_CAPABILITY_NOT_METERED)
+    }
+
     /** Where a download goes: app-private, so no storage permission is involved. */
     fun downloadTarget(context: Context): File = File(context.cacheDir, "update.apk")
 

android/app/src/main/java/com/fabledsword/thoughtsync/MainActivity.kt

@@ -25,8 +25,8 @@ import androidx.lifecycle.viewmodel.compose.viewModel
 import com.fabledsword.thoughtsync.core.ThoughtSync
 import com.fabledsword.thoughtsync.ui.BoardScreen
 import com.fabledsword.thoughtsync.ui.BoardSync
+import com.fabledsword.thoughtsync.ui.BoardUpdate
 import com.fabledsword.thoughtsync.ui.BoardViewModel
-import com.fabledsword.thoughtsync.ui.ComposeSheet
 import com.fabledsword.thoughtsync.ui.ForegroundTransitions
 import com.fabledsword.thoughtsync.ui.NoteEditorScreen
 import com.fabledsword.thoughtsync.ui.StoreUnavailableScreen
@@ -141,14 +141,13 @@ private fun App(
     val sync: SyncViewModel =
         viewModel(factory = SyncViewModel.factory(core, onStoreChanged = board::refresh))
 
-    // Sheet and screen visibility are view STATE, not view-model state: they are
-    // about what is on the display, and nothing in the store cares.
+    // Screen visibility is view STATE, not view-model state: it is about what is on
+    // the display, and nothing in the store cares. Saveable so a rotation does not
+    // close it.
     //
-    // Saveable, though: `remember` alone meant rotating the phone closed whatever
-    // was open and took the half-written note in the capture sheet with it. The
-    // editor never had that problem because the note it is on lives in a view
-    // model; these two are the only screen state that did not.
-    var composing by rememberSaveable { mutableStateOf(false) }
+    // The capture sheet used to keep its own flag here too. It is gone: the + button
+    // opens the editor on an unsaved draft, so writing a note and editing one are the
+    // same surface with the same toolbar.
     var showingSync by rememberSaveable { mutableStateOf(false) }
 
     val update: UpdateViewModel = viewModel(factory = UpdateViewModel.factory(core, context))
@@ -156,6 +155,7 @@ private fun App(
     var automatic by remember { mutableStateOf(settings.automatic) }
 
     AutomaticSync(state = sync.state, enabled = automatic, onSync = sync::syncQuietly)
+    AutomaticUpdate(linked = sync.state.linked, onCheck = update::checkInBackground)
 
     val editing = board.state.editing
     val screen =
@@ -192,6 +192,7 @@ private fun App(
             NoteEditorScreen(
                 // Non-null by construction: `screen` is EDITOR only when it is.
                 note = requireNotNull(editing) { "the editor screen needs a note" },
+                sessionKey = board.state.editingSession,
                 labels = board.state.labels,
                 saving = board.state.saving,
                 error = board.state.error,
@@ -218,20 +219,23 @@ private fun App(
                     ),
                 onOpenSync = { showingSync = true },
                 onSearch = board::search,
-                onCompose = { composing = true },
+                onCompose = board::compose,
+                onToggleItem = board::toggleItem,
+                // Null unless there is genuinely something to say — the board is
+                // handed a decision, not a state to interpret.
+                update =
+                    update.state.available
+                        ?.takeIf { update.state.nagging }
+                        ?.let {
+                            BoardUpdate(
+                                version = it.version,
+                                busy = update.state.busy,
+                                onInstall = update::downloadAndInstall,
+                                onDismiss = update::dismissNag,
+                            )
+                        },
                 onDismissError = board::dismissError,
             )
-
-            if (composing) {
-                ComposeSheet(
-                    saving = board.state.saving,
-                    onDismiss = { composing = false },
-                    onSave = { content ->
-                        board.create(content)
-                        composing = false
-                    },
-                )
-            }
         }
     }
 
@@ -282,6 +286,36 @@ private fun ReminderAlarms(core: ThoughtSync) {
     }
 }
 
+/**
+ * Looking for an app update without being asked.
+ *
+ * Until this existed, `check()` had exactly one caller: a button on the sync screen.
+ * So a new build was found only by someone who went looking for one, and the operator
+ * had to remember to go looking — which is the same as not being told.
+ *
+ * On coming forward rather than on a timer: it is the moment the person is present,
+ * and the view model rate-limits so flicking between two apps is not a re-check.
+ * Unlinked devices are skipped entirely — updates come from a linked server, and
+ * there is nothing to ask.
+ */
+@Composable
+private fun AutomaticUpdate(
+    linked: Boolean,
+    onCheck: () -> Unit,
+) {
+    var wanted by remember { mutableStateOf(false) }
+    ForegroundTransitions(onForeground = { wanted = true }, onBackground = {})
+
+    LaunchedEffect(wanted, linked) {
+        if (!wanted || !linked) return@LaunchedEffect
+        // Consumed here, so this fires once per trip to the foreground however many
+        // times the effect restarts. There is no suspension point before the call, so
+        // the block completes before the recomposition that would cancel it.
+        wanted = false
+        onCheck()
+    }
+}
+
 /**
  * Syncing without being asked.
  *

android/app/src/main/java/com/fabledsword/thoughtsync/ui/BlockBody.kt

@@ -0,0 +1,242 @@
+package com.fabledsword.thoughtsync.ui
+
+import androidx.annotation.StringRes
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.text.BasicTextField
+import androidx.compose.foundation.text.KeyboardActions
+import androidx.compose.foundation.text.KeyboardOptions
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Close
+import androidx.compose.material3.Checkbox
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.LocalMinimumInteractiveComponentSize
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.CompositionLocalProvider
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.remember
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.focus.FocusRequester
+import androidx.compose.ui.focus.focusRequester
+import androidx.compose.ui.graphics.SolidColor
+import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.text.TextStyle
+import androidx.compose.ui.text.input.ImeAction
+import androidx.compose.ui.text.input.TextFieldValue
+import androidx.compose.ui.text.style.TextDecoration
+import androidx.compose.ui.unit.dp
+import com.fabledsword.thoughtsync.R
+
+/**
+ * The note's body, as fields and checkboxes rather than as markup.
+ *
+ * The point of the whole shape: a box you can tick while looking at the note, rather
+ * than `- [ ] ` to read and edit around. What the note IS never changed.
+ */
+@Composable
+fun BlockBody(
+    blocks: List<EditorBlock>,
+    readOnly: Boolean,
+    focus: Long?,
+    onChange: (List<EditorBlock>) -> Unit,
+    onFocus: (Long?) -> Unit,
+    modifier: Modifier = Modifier,
+) {
+    // Focus is addressed by block ID, never by position — the id is the only thing
+    // about a block that survives one being inserted above it. Hoisted to the caller
+    // rather than kept here, because the TOOLBAR also asks for a focus when its button
+    // appends an item, and two owners of one cursor is one too many.
+    val requesters = remember { mutableMapOf<Long, FocusRequester>() }
+
+    LaunchedEffect(focus) {
+        val id = focus ?: return@LaunchedEffect
+        // Honoured after the composition that created the field: a FocusRequester not
+        // yet attached to anything throws when asked.
+        requesters[id]?.requestFocus()
+        onFocus(null)
+    }
+
+    fun replace(
+        index: Int,
+        block: EditorBlock,
+    ) = onChange(blocks.toMutableList().also { it[index] = block })
+
+    Column(modifier = modifier, verticalArrangement = Arrangement.spacedBy(2.dp)) {
+        blocks.forEachIndexed { index, block ->
+            val requester = requesters.getOrPut(block.id) { FocusRequester() }
+            if (block.isTask) {
+                TaskBlock(
+                    block = block,
+                    readOnly = readOnly,
+                    requester = requester,
+                    onChange = { replace(index, it) },
+                    onEnter = {
+                        val next = blocks.nextId()
+                        onChange(afterEnter(blocks, index, next))
+                        // The new item if there was one; otherwise the block that just
+                        // became prose, which keeps the caret where the person left it.
+                        onFocus(if (blocks[index].value.text.isBlank()) block.id else next)
+                    },
+                    onDelete = {
+                        val remaining = blocks.withoutIndex(index)
+                        onChange(remaining)
+                        // The row above — or, for the FIRST row, whichever one takes
+                        // its place. `index - 1` alone is -1 there, which left the
+                        // keyboard up with nothing focused.
+                        onFocus(remaining.getOrNull((index - 1).coerceAtLeast(0))?.id)
+                    },
+                )
+            } else {
+                ProseBlock(
+                    block = block,
+                    readOnly = readOnly,
+                    requester = requester,
+                    onChange = { replace(index, it) },
+                )
+            }
+        }
+    }
+}
+
+/** A run of prose: one ordinary multi-line field, exactly as the editor always had. */
+@Composable
+private fun ProseBlock(
+    block: EditorBlock,
+    readOnly: Boolean,
+    requester: FocusRequester,
+    onChange: (EditorBlock) -> Unit,
+) {
+    BlockField(
+        value = block.value,
+        onValueChange = { onChange(block.copy(value = it)) },
+        modifier = Modifier.focusRequester(requester),
+        enabled = !readOnly,
+        hint = R.string.editor_body_hint,
+    )
+}
+
+/**
+ * One checklist item: a real box, and the item's text beside it.
+ *
+ * Single-line with [ImeAction.Next], which is what turns the keyboard's return key
+ * into "next item" — the reason a list can be typed straight through rather than a
+ * marker at a time.
+ */
+@Composable
+private fun TaskBlock(
+    block: EditorBlock,
+    readOnly: Boolean,
+    requester: FocusRequester,
+    onChange: (EditorBlock) -> Unit,
+    onEnter: () -> Unit,
+    onDelete: () -> Unit,
+) {
+    // Material sizes every interactive component to a 48dp touch target, and on a
+    // checklist that IS the row height — which is why six items filled a phone screen
+    // even after the field's own padding came off.
+    CompositionLocalProvider(LocalMinimumInteractiveComponentSize provides ROW_TOUCH) {
+        Row(verticalAlignment = Alignment.CenterVertically) {
+            Checkbox(
+                checked = block.checked == true,
+                onCheckedChange = { onChange(block.copy(checked = it)) },
+                enabled = !readOnly,
+            )
+            BlockField(
+                value = block.value,
+                onValueChange = { onChange(block.copy(value = it)) },
+                modifier = Modifier.weight(1f).focusRequester(requester),
+                enabled = !readOnly,
+                singleLine = true,
+                textStyle =
+                    MaterialTheme.typography.bodyLarge.copy(
+                        // Struck through when done, matching the card and the web.
+                        textDecoration =
+                            if (block.checked == true) TextDecoration.LineThrough else null,
+                    ),
+                keyboardOptions = KeyboardOptions(imeAction = ImeAction.Next),
+                keyboardActions = KeyboardActions(onNext = { onEnter() }),
+            )
+            if (!readOnly) {
+                IconButton(onClick = onDelete) {
+                    Icon(
+                        Icons.Filled.Close,
+                        contentDescription = stringResource(R.string.editor_remove_item),
+                    )
+                }
+            }
+        }
+    }
+}
+
+/**
+ * The touch target for a checklist row's controls.
+ *
+ * Material's floor is 48dp and this is deliberately under it. That floor is sized for
+ * a control somebody has to find; a checklist box sits in a predictable column with an
+ * identical box directly above and below, and the cost of a near miss is ticking the
+ * neighbouring item — visible, and undone by tapping again. Trading twelve of those
+ * dp for a list that fits on a screen is what was asked for, twice.
+ */
+private val ROW_TOUCH = 36.dp
+
+/**
+ * The field a block is typed into.
+ *
+ * `BasicTextField`, not the Material one [PlainTextField] wraps, and the reason is
+ * density. Material's TextField puts 16dp above and below its text — padding that
+ * makes a FORM field comfortable to hit, and that on a checklist IS the row height. It
+ * made six items twice as tall as the six items, which is what the operator saw.
+ *
+ * Nothing is lost by dropping down a layer. `PlainTextField` exists to strip a
+ * container and an indicator; `BasicTextField` never had either, so there is no box
+ * here to drift back into existence. What it does not supply and this must:
+ *
+ *  - the text COLOUR. It defaults to `Color.Unspecified`, which draws BLACK — the same
+ *    default that made the editor's toolbar invisible in dark mode. Set, not inherited.
+ *  - the cursor brush, which would otherwise be black for the same reason.
+ *  - the placeholder, which is a plain Text behind the field rather than a slot.
+ *
+ * `enabled = false` deliberately does not grey the text out: a trashed note renders
+ * read-only through this and its words are meant to be READ.
+ */
+@Composable
+private fun BlockField(
+    value: TextFieldValue,
+    onValueChange: (TextFieldValue) -> Unit,
+    modifier: Modifier = Modifier,
+    enabled: Boolean = true,
+    singleLine: Boolean = false,
+    @StringRes hint: Int? = null,
+    textStyle: TextStyle = MaterialTheme.typography.bodyLarge,
+    keyboardOptions: KeyboardOptions = KeyboardOptions.Default,
+    keyboardActions: KeyboardActions = KeyboardActions.Default,
+) {
+    val style = textStyle.copy(color = MaterialTheme.colorScheme.onSurface)
+    Box(modifier = modifier) {
+        if (hint != null && value.text.isEmpty()) {
+            Text(
+                text = stringResource(hint),
+                style = style,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+            )
+        }
+        BasicTextField(
+            value = value,
+            onValueChange = onValueChange,
+            modifier = Modifier.fillMaxWidth(),
+            enabled = enabled,
+            singleLine = singleLine,
+            textStyle = style,
+            keyboardOptions = keyboardOptions,
+            keyboardActions = keyboardActions,
+            cursorBrush = SolidColor(MaterialTheme.colorScheme.primary),
+        )
+    }
+}

android/app/src/main/java/com/fabledsword/thoughtsync/ui/BoardScreen.kt

@@ -64,6 +64,8 @@ fun BoardScreen(
     onOpenSync: () -> Unit,
     onSearch: (String) -> Unit,
     onCompose: () -> Unit,
+    onToggleItem: (Note, Int, Boolean) -> Unit,
+    update: BoardUpdate?,
     onDismissError: () -> Unit,
 ) {
     val drawerState = rememberDrawerState(DrawerValue.Closed)
@@ -117,6 +119,17 @@ fun BoardScreen(
                     ErrorBanner(message = message, onDismiss = sync.onDismissError)
                 }
 
+                // Below the failures and above the notes: an update is worth saying,
+                // and never worth saying before a note failed to save.
+                update?.let {
+                    UpdateBanner(
+                        version = it.version,
+                        busy = it.busy,
+                        onInstall = it.onInstall,
+                        onDismiss = it.onDismiss,
+                    )
+                }
+
                 // Only where someone is already thinking about reminders. On the
                 // main board it would nag people who have never set one.
                 if (state.destination == Destination.Reminders) ReminderNotice()
@@ -140,7 +153,12 @@ fun BoardScreen(
                     when {
                         state.loading -> LoadingBoard()
                         state.notes.isEmpty() -> EmptyBoard(state)
-                        else -> NoteBoard(notes = state.notes, onOpenNote = onOpenNote)
+                        else ->
+                            NoteBoard(
+                                notes = state.notes,
+                                onOpenNote = onOpenNote,
+                                onToggleItem = onToggleItem,
+                            )
                     }
                     // `PullToRefreshBox` would be less code, but it takes no
                     // `enabled`, so the modifier and the indicator are wired by
@@ -181,6 +199,25 @@ data class BoardSync(
     val onDismissError: () -> Unit,
 )
 
+/**
+ * The waiting app update, or null when there is nothing to say.
+ *
+ * A holder rather than five loose parameters, for the same reason [BoardSync] is one:
+ * `version` and a pair of booleans as positional arguments could be swapped with
+ * nothing to catch it.
+ *
+ * Null covers every reason there is nothing to show — unlinked, up to date, found but
+ * not yet downloaded, dismissed for this sitting — so the board never has to know
+ * which.
+ */
+data class BoardUpdate(
+    val version: String,
+    /** An install is in flight — the banner stays and reports it. */
+    val busy: Boolean,
+    val onInstall: () -> Unit,
+    val onDismiss: () -> Unit,
+)
+
 /**
  * A search field IS the top bar, following the phone convention rather than the
  * desktop's title-plus-sidebar.
@@ -323,6 +360,7 @@ private fun DrawerRow(
 private fun NoteBoard(
     notes: List<Note>,
     onOpenNote: (Note) -> Unit,
+    onToggleItem: (Note, Int, Boolean) -> Unit,
 ) {
     LazyVerticalStaggeredGrid(
         columns = StaggeredGridCells.Fixed(BOARD_COLUMNS),
@@ -336,7 +374,11 @@ private fun NoteBoard(
         // rebuilding them — and so a newly captured note slides in instead of
         // making every card below it flicker.
         items(items = notes, key = { it.id }) { note ->
-            NoteCard(note = note, onOpen = { onOpenNote(note) })
+            NoteCard(
+                note = note,
+                onOpen = { onOpenNote(note) },
+                onToggleItem = { index, checked -> onToggleItem(note, index, checked) },
+            )
         }
     }
 }

android/app/src/main/java/com/fabledsword/thoughtsync/ui/BoardViewModel.kt

@@ -68,6 +68,16 @@ data class BoardState(
      * has to re-query to see its own change.
      */
     val editing: Note? = null,
+    /**
+     * Bumped each time the editor is opened on a DIFFERENT note, and deliberately
+     * not when the note it is already on changes.
+     *
+     * The editor keys its text field on this rather than on `editing.id`, because a
+     * draft's id changes the instant it is first saved — and re-keying on that would
+     * reset the field to whatever the store just returned, discarding anything typed
+     * during the write. That is a data-loss bug rather than a flicker.
+     */
+    val editingSession: Long = 0,
 ) {
     /** Search overrides the destination while there is a query to run. */
     val searching: Boolean get() = query.isNotBlank()
@@ -188,44 +198,6 @@ class BoardViewModel(
             }
     }
 
-    /**
-     * Save a new note or list.
-     *
-     * Blank input is ignored rather than rejected: an empty save is a slip, not a
-     * mistake worth interrupting someone over.
-     */
-    fun create(content: String) {
-        val cleanContent = content.trim()
-        if (cleanContent.isEmpty()) return
-
-        viewModelScope.launch {
-            state = state.copy(saving = true)
-            state =
-                try {
-                    val created = withContext(Dispatchers.IO) { core.createNote(draft(cleanContent)) }
-                    // Prepend rather than reload: the new note belongs at the top
-                    // of the board, and a full re-query would cost a round trip to
-                    // tell us what we already know. Skipped when the board is not
-                    // showing plain notes — a note created while looking at Trash
-                    // does not belong in that list.
-                    val notes =
-                        if (state.destination == Destination.Notes && !state.searching) {
-                            listOf(created) + state.notes
-                        } else {
-                            state.notes
-                        }
-                    // A capture sheet can carry a reminder in its text one day;
-                    // more to the point, this is a store write and the rule here is
-                    // that every store write re-derives the alarm rather than each
-                    // call site deciding whether its particular write could matter.
-                    withContext(Dispatchers.IO) { onRemindersChanged() }
-                    state.copy(notes = notes, saving = false, error = null)
-                } catch (e: Exception) {
-                    state.copy(saving = false, error = e.message ?: FALLBACK_ERROR)
-                }
-        }
-    }
-
     // ───────────────────────────────  the editor  ──────────────────────────────
 
     /**
@@ -238,12 +210,111 @@ class BoardViewModel(
     fun openNoteById(id: String) {
         viewModelScope.launch {
             runCatching { withContext(Dispatchers.IO) { core.getNote(id) } }
-                .onSuccess { state = state.copy(editing = it) }
+                .onSuccess { state = state.copy(editing = it, editingSession = state.editingSession + 1) }
         }
     }
 
     fun openNote(note: Note) {
-        state = state.copy(editing = note)
+        state = state.copy(editing = note, editingSession = state.editingSession + 1)
+    }
+
+    /**
+     * Open the editor on a note that does not exist yet.
+     *
+     * The + button used to raise a separate capture sheet, which meant a note being
+     * WRITTEN could not be given a colour, a reminder or a checklist — those live on
+     * the editor's toolbar, and the sheet had none. Writing and editing are now the
+     * same surface.
+     *
+     * The draft is a real [Note] carrying [DRAFT_ID] rather than a null, so the
+     * editor renders it without knowing that "not saved yet" is a state it can be
+     * in. It becomes a row on its first save; see [onDraftAction].
+     */
+    fun compose() {
+        draftDismissed = false
+        state = state.copy(editing = blankDraft(), editingSession = state.editingSession + 1)
+    }
+
+    /**
+     * Set when a draft's editor closes, so a create still in flight does not reopen
+     * it. The editor flushes its text and then closes, and the flush is a coroutine —
+     * without this the note would be created, the screen would close, and the create
+     * would finish and put the screen back.
+     */
+    private var draftDismissed = false
+
+    /**
+     * The editor's actions, for a note that has no row yet.
+     *
+     * Everything a toolbar button does needs an id to act on, so the first action
+     * that needs one creates the note and replays itself against the real thing.
+     */
+    private fun onDraftAction(
+        draft: Note,
+        action: EditorAction,
+    ) {
+        when (action) {
+            // Nothing exists, so leaving leaves nothing behind — which is what makes
+            // tapping + and changing your mind free. Text typed before this point has
+            // already gone to createFromDraft via the editor's autosave or its flush.
+            EditorAction.Close, EditorAction.Trash -> {
+                draftDismissed = true
+                state = state.copy(editing = null)
+            }
+            EditorAction.DismissError -> dismissError()
+            is EditorAction.SaveText -> createFromDraft(action.body)
+            // Colour, reminder, pin, labels: attributes OF a note, so there has to be
+            // a note. With autosave at a second, "typed something" is true by the time
+            // anyone reaches the toolbar; before that there is nothing to attribute.
+            else -> createFromDraft(draft.body) { created -> onEditorAction(created, action) }
+        }
+    }
+
+    /**
+     * Turn a draft into a row, and keep the editor on it.
+     *
+     * Adopting the created note is what lets a session of autosaves stay one note:
+     * the second save sees a real id and updates rather than creating again.
+     */
+    private fun createFromDraft(
+        content: String,
+        allowEmpty: Boolean = false,
+        then: (Note) -> Unit = {},
+    ) {
+        val cleanContent = content.trim()
+        // A blank draft is not a note. Ignored rather than rejected: tapping + and
+        // walking away is a slip, not a mistake worth interrupting someone over.
+        if (cleanContent.isEmpty() && !allowEmpty) return
+        viewModelScope.launch {
+            state = state.copy(saving = true)
+            state =
+                try {
+                    val created = withContext(Dispatchers.IO) { core.createNote(draft(cleanContent)) }
+                    // Prepend rather than reload: the new note belongs at the top of
+                    // the board, and a full re-query would cost a round trip to tell
+                    // us what we already know. Skipped when the board is not showing
+                    // plain notes — a note created while looking at Trash does not
+                    // belong in that list.
+                    val notes =
+                        if (state.destination == Destination.Notes && !state.searching) {
+                            listOf(created) + state.notes
+                        } else {
+                            state.notes
+                        }
+                    withContext(Dispatchers.IO) { onRemindersChanged() }
+                    // editingSession is NOT bumped: this is the same sitting, and the
+                    // editor's field must not be re-keyed underneath the typing.
+                    state.copy(
+                        notes = notes,
+                        editing = if (draftDismissed) state.editing else created,
+                        saving = false,
+                        error = null,
+                    )
+                } catch (e: Exception) {
+                    state.copy(saving = false, error = e.message ?: FALLBACK_ERROR)
+                }
+            if (!draftDismissed) state.editing?.let(then)
+        }
     }
 
     /**
@@ -268,13 +339,18 @@ class BoardViewModel(
         note: Note,
         action: EditorAction,
     ) {
+        if (note.id == DRAFT_ID) {
+            onDraftAction(note, action)
+            return
+        }
         val id = note.id
         when (action) {
             EditorAction.Close -> state = state.copy(editing = null)
             EditorAction.DismissError -> dismissError()
 
-            // Saved on close rather than per keystroke, so a session of typing
-            // costs one write and one revision snapshot.
+            // Sent on an idle debounce while typing, and again on close. Writing
+            // this often is affordable because a body write no longer snapshots a
+            // revision — the core keeps one per editing session, not one per save.
             is EditorAction.SaveText ->
                 mutate { it.updateNote(id, listOf(NoteEdit.Body(action.body))) }
 
@@ -302,20 +378,6 @@ class BoardViewModel(
                     null
                 }
 
-            // An empty first item: the checklist editor appears the moment the note
-            // has one, and an empty row is what someone can type straight into.
-            EditorAction.AddChecklist -> mutate { it.addItem(id, "") }
-
-            is EditorAction.AddItem ->
-                action.text.trim().takeIf { it.isNotEmpty() }?.let { text ->
-                    mutate { it.addItem(id, text) }
-                }
-            is EditorAction.SetItemChecked ->
-                mutate { it.setItemChecked(id, action.itemId, action.checked) }
-            is EditorAction.SetItemText ->
-                mutate { it.setItemText(id, action.itemId, action.text) }
-            is EditorAction.DeleteItem -> mutate { it.deleteItem(id, action.itemId) }
-
             is EditorAction.SetLabels -> mutate { it.setNoteLabels(id, action.labelIds) }
 
             is EditorAction.CreateLabel ->
@@ -351,9 +413,10 @@ class BoardViewModel(
     /**
      * The one path every store mutation takes.
      *
-     * Each core mutation returns the reloaded note, which goes straight into
-     * [BoardState.editing] so an open editor shows its own change without a
-     * re-query. The BOARD list is then reloaded rather than patched in place:
+     * Each core mutation returns the reloaded note, which refreshes
+     * [BoardState.editing] so an OPEN editor shows its own change without a
+     * re-query — and does nothing at all when the editor is closed, because that
+     * field doubles as "which screen is up". The BOARD list is then reloaded rather than patched in place:
      * pinning re-sorts it, archiving removes the note from it, and adding a label
      * can move it in or out of a label view — a splice would have to reimplement
      * the core's ordering and membership rules in Kotlin to get any of that right.
@@ -389,7 +452,12 @@ class BoardViewModel(
                     withContext(Dispatchers.IO) { onRemindersChanged() }
                     state.copy(
                         notes = notes,
-                        editing = if (closeEditor) null else updated ?: state.editing,
+                        // Only REFRESHES an open editor; it must never open one.
+                        // `editing != null` IS "the editor is on screen", so writing
+                        // the reloaded note in unconditionally meant any mutation
+                        // started from the BOARD threw the editor open on top of it —
+                        // which is exactly what ticking a checkbox on a card did.
+                        editing = if (closeEditor) null else state.editing?.let { updated ?: it },
                         saving = false,
                         error = null,
                     )
@@ -402,6 +470,21 @@ class BoardViewModel(
         }
     }
 
+    /**
+     * Tick or untick one item from the BOARD, without opening the note.
+     *
+     * The common gesture on a checklist, and the reason it goes through the store
+     * rather than the pure text helpers the editor uses: nothing here is holding a
+     * half-typed body, so the reloaded note is simply the truth.
+     *
+     * `index` is the item's ordinal, which is what its id is now (M304).
+     */
+    fun toggleItem(
+        note: Note,
+        index: Int,
+        checked: Boolean,
+    ) = mutate { it.setItemChecked(note.id, index.toString(), checked) }
+
     fun dismissError() {
         state = state.copy(error = null)
     }
@@ -447,3 +530,33 @@ private fun draft(content: String): NoteDraft =
     // findable without anyone being asked to name it. A checklist is added afterwards,
     // in the editor — it is something a note HAS, not a different thing to capture.
     NoteDraft(body = content, color = DEFAULT_COLOR, items = null)
+
+/**
+ * The id a note has before it has been saved.
+ *
+ * A real id is a uuid, so the empty string cannot collide with one. Using a sentinel
+ * rather than making the editor's note nullable keeps "not saved yet" out of a screen
+ * that reads eight fields off the note and should not have to null-check any of them.
+ */
+internal const val DRAFT_ID = ""
+
+private fun blankDraft(): Note =
+    Note(
+        id = DRAFT_ID,
+        displayTitle = "",
+        body = "",
+        color = DEFAULT_COLOR,
+        position = 0,
+        pinned = false,
+        archived = false,
+        trashed = false,
+        deletedAt = null,
+        remindAt = null,
+        recurrence = null,
+        labels = emptyList(),
+        items = emptyList(),
+        attachments = emptyList(),
+        previews = emptyList(),
+        createdAt = null,
+        updatedAt = null,
+    )

android/app/src/main/java/com/fabledsword/thoughtsync/ui/ComposeSheet.kt

@@ -1,130 +0,0 @@
-package com.fabledsword.thoughtsync.ui
-
-import androidx.compose.foundation.layout.Arrangement
-import androidx.compose.foundation.layout.Column
-import androidx.compose.foundation.layout.Row
-import androidx.compose.foundation.layout.fillMaxWidth
-import androidx.compose.foundation.layout.imePadding
-import androidx.compose.foundation.layout.navigationBarsPadding
-import androidx.compose.foundation.layout.padding
-import androidx.compose.material3.Button
-import androidx.compose.material3.ExperimentalMaterial3Api
-import androidx.compose.material3.ModalBottomSheet
-import androidx.compose.material3.Text
-import androidx.compose.material3.TextButton
-import androidx.compose.material3.rememberModalBottomSheetState
-import androidx.compose.runtime.Composable
-import androidx.compose.runtime.LaunchedEffect
-import androidx.compose.runtime.getValue
-import androidx.compose.runtime.mutableStateOf
-import androidx.compose.runtime.remember
-import androidx.compose.runtime.saveable.rememberSaveable
-import androidx.compose.runtime.setValue
-import androidx.compose.ui.Modifier
-import androidx.compose.ui.focus.FocusRequester
-import androidx.compose.ui.focus.focusRequester
-import androidx.compose.ui.res.stringResource
-import androidx.compose.ui.unit.dp
-import com.fabledsword.thoughtsync.R
-
-/**
- * The new-note surface, opened by the + button.
- *
- * A bottom sheet rather than a full screen: capture should feel like a quick aside
- * from the board, not a place you navigate to and have to come back from. The
- * board stays visible behind it, so the note lands somewhere you can already see.
- *
- * It asks note-or-list up front rather than making that a mode you discover later,
- * because on a phone the two are genuinely different typing tasks and switching
- * halfway is worse than choosing at the start.
- *
- * ## Leaving keeps what you wrote
- *
- * Every way out of this sheet except Discard SAVES: the save button, tapping the
- * board behind it, swiping down, back, and the app being backgrounded. A sheet
- * that throws away a typed thought because you touched outside it is a sheet that
- * teaches people not to trust the app with a thought — and capture is the one
- * place this product cannot afford that.
- *
- * The same shape the editor settled on, for the same reason, with one difference:
- * capture also has to be abandonable, because tapping + and changing your mind is
- * a normal thing to do. That is what Discard is, and it is the only path that
- * loses anything. An empty draft needs neither — it is simply dropped, since a
- * blank note nobody asked for is worse than no note at all.
- */
-@OptIn(ExperimentalMaterial3Api::class)
-@Composable
-fun ComposeSheet(
-    saving: Boolean,
-    onDismiss: () -> Unit,
-    onSave: (String) -> Unit,
-) {
-    val sheetState = rememberModalBottomSheetState(skipPartiallyExpanded = true)
-    // Saveable, not just remembered: a rotation mid-sentence is the same lost
-    // thought as a discarded one, and it was losing it before this.
-    var content by rememberSaveable { mutableStateOf("") }
-    val contentFocus = remember { FocusRequester() }
-
-    val written = content.isNotBlank()
-    val leave = { if (written) onSave(content) else onDismiss() }
-
-    // Straight into the one field there is. A capture is a thought, and every field
-    // someone has to tab past is the difference between "under a second" and not —
-    // which is why the title field is gone rather than merely skipped (M13 step 3).
-    LaunchedEffect(Unit) { contentFocus.requestFocus() }
-
-    // Backgrounding PERSISTS but does not close an empty sheet. Someone who tapped
-    // + and then got distracted should find the composer where they left it; the
-    // only reason to act here is that there is something to lose.
-    FlushOnStop { if (written) onSave(content) }
-
-    ModalBottomSheet(onDismissRequest = leave, sheetState = sheetState) {
-        Column(
-            modifier =
-                Modifier
-                    .fillMaxWidth()
-                    .padding(horizontal = 16.dp)
-                    .imePadding()
-                    .navigationBarsPadding(),
-            verticalArrangement = Arrangement.spacedBy(8.dp),
-        ) {
-            // No note/list switch any more: there is one thing to capture. A
-            // checklist is added to a note in the editor, once there is a note.
-            PlainTextField(
-                value = content,
-                onValueChange = { content = it },
-                modifier = Modifier.focusRequester(contentFocus),
-                hint = R.string.compose_body_hint,
-                minLines = MIN_CONTENT_LINES,
-            )
-
-            SheetActions(
-                canSave = !saving && written,
-                onDiscard = onDismiss,
-                onSave = { onSave(content) },
-            )
-        }
-    }
-}
-
-@Composable
-private fun SheetActions(
-    canSave: Boolean,
-    onDiscard: () -> Unit,
-    onSave: () -> Unit,
-) {
-    Row(
-        modifier = Modifier.fillMaxWidth().padding(bottom = 16.dp),
-        horizontalArrangement = Arrangement.End,
-    ) {
-        // "Discard", not "Cancel". Cancel means "undo what I am doing", which is
-        // precisely what leaving no longer does — the word would now describe the
-        // one button it is NOT attached to.
-        TextButton(onClick = onDiscard) { Text(stringResource(R.string.compose_discard)) }
-        Button(onClick = onSave, enabled = canSave) {
-            Text(stringResource(R.string.compose_save))
-        }
-    }
-}
-
-private const val MIN_CONTENT_LINES = 4

android/app/src/main/java/com/fabledsword/thoughtsync/ui/DerivedTint.kt

@@ -0,0 +1,294 @@
+package com.fabledsword.thoughtsync.ui
+
+import kotlin.math.abs
+
+// The colour a note has when nothing chose one for it.
+//
+// A board of `default` notes is a wall of white rectangles and the eye gets no help
+// telling one from the next. Every note now carries some tint; this is where an
+// untagged one gets it.
+//
+// "RANDOM" MEANS DERIVED. The operator asked for "random subdued colors", but a tint
+// rolled at render time would differ between the phone and the browser and change on
+// every reload. Hashing the note's id is deterministic, identical on every surface,
+// costs no column and no migration, and a note keeps its colour for life — which is
+// what "random" actually meant here.
+//
+// THIS IS HALF A MIRRORED PAIR. `frontend/src/notes/colors.ts` computes the same hash
+// over the same key order, and the two must agree exactly or a note is one colour on
+// the phone and another in the browser. Same discipline as the checklist grammar's
+// three implementations, and the same reason: a value that disagrees across surfaces
+// is a bug you cannot unsee and cannot explain.
+//
+// NO COMPOSE IN THIS FILE, deliberately. It is the half of the pair that CAN be
+// pinned by a host-JVM test, and staying free of `androidx.compose` is what keeps
+// `DerivedTintTest` runnable in the Unit tests step rather than on an emulator. The
+// web side has no test runner at all, so this test is the only mechanical guard the
+// mirror gets — see the fixture comment in colors.ts.
+
+/**
+ * The tints a derived colour can land on: `NOTE_TINTS`' keys minus `default`, which
+ * is the white this exists to eliminate. `gray` stays — `bg-neutral-100` reads as a
+ * deliberate card against the board's `bg-neutral-50`, not as an absence.
+ *
+ * Order is load-bearing and matches `DERIVED_TINT_KEYS` in colors.ts. Reordering
+ * this list silently recolours every untagged note on one surface only.
+ */
+val DERIVED_TINT_KEYS: List<String> =
+    listOf("red", "orange", "yellow", "green", "teal", "blue", "purple", "pink", "gray")
+
+private const val FNV_OFFSET_BASIS = -0x7ee3623b // 0x811c9dc5 as a signed Int
+private const val FNV_PRIME = 0x01000193
+private const val BYTE_MASK = 0xFF
+private const val UNSIGNED_MASK = 0xFFFFFFFFL
+
+/**
+ * FNV-1a over the id's bytes, 32-bit.
+ *
+ * Chosen because both languages compute it identically in ten lines with no library.
+ * Explicitly NOT `String.hashCode()`: Kotlin's is specified but JS has no equivalent,
+ * and reimplementing Java's from memory in TypeScript is exactly how a mirror drifts.
+ *
+ * `and BYTE_MASK` is a no-op for the ASCII of a UUID, and is kept because it states
+ * the intent — this hashes BYTES, so the TypeScript side reading `charCodeAt(i) &
+ * 0xff` is the same function rather than a coincidence.
+ *
+ * Overflow is the point: Kotlin's `Int` wraps on multiply, which is what the web's
+ * `Math.imul` exists to reproduce.
+ */
+fun tintHash(id: String): Int {
+    var hash = FNV_OFFSET_BASIS
+    for (ch in id) {
+        hash = hash xor (ch.code and BYTE_MASK)
+        hash *= FNV_PRIME
+    }
+    return hash
+}
+
+/** The tint a note with no colour of its own wears. Stable for the life of the note. */
+fun derivedTint(id: String): String {
+    // Through Long to read the hash as unsigned. A signed remainder would be negative
+    // for half of all ids and index out of the list.
+    val index = (tintHash(id).toLong() and UNSIGNED_MASK) % DERIVED_TINT_KEYS.size
+    return DERIVED_TINT_KEYS[index.toInt()]
+}
+
+/**
+ * The colour key for a LABEL — its chip, and (step 3) every note carrying it.
+ *
+ * Derived from the tag's NAME when nobody has picked one. Every `#tag` ever typed is
+ * currently `default`: the server mints one as `Label(owner_id=…, name=name)` with no
+ * colour, so tag-driven note colour against that would leave the board exactly as
+ * grey as it was.
+ *
+ * DERIVED RATHER THAN PERSISTED AT MINT TIME, reversing #2965's plan. That plan wanted
+ * a hashed colour written at each of the four places a label can be born — and named
+ * the risk itself: `find_or_create_label` is "easy to miss, and it is the common one",
+ * since most tags are born from typing `#grocery`, not from a management screen.
+ * Deriving has no mint points to miss and no backfill for the tags already out there.
+ * The cost is that renaming a tag recolours it, which is fair: the name IS the tag.
+ *
+ * Lowercased because tags dedupe case-insensitively — `#Todo` renamed to `#todo` is
+ * the same tag and should not change colour. Kotlin's `lowercase()` and the web's
+ * `toLowerCase()` are both locale-independent, so the mirror holds.
+ */
+fun resolvedLabelColor(
+    name: String,
+    color: String,
+    known: Set<String>,
+): String =
+    when {
+        color.isNotEmpty() && color != "default" && color in known -> color
+        name.isEmpty() -> "default"
+        else -> derivedTint(name.lowercase())
+    }
+
+/**
+ * The colour key to actually paint a note with.
+ *
+ * An explicitly-picked colour still wins — the picker is on its way out (milestone
+ * 309 step 5) but it has not gone yet, and a note the operator coloured by hand
+ * changing under them would read as data loss.
+ *
+ * `known` is passed in rather than read from `NOTE_TINTS` so this file stays free of
+ * Compose and therefore testable; `noteTintFor` supplies the real set.
+ */
+fun resolvedNoteColor(
+    id: String,
+    color: String,
+    labelColor: String,
+    known: Set<String>,
+): String =
+    when {
+        color.isNotEmpty() && color != "default" && color in known -> color
+        // The note's FIRST tag. Passed in already resolved, so this does not need to
+        // know that a colourless tag derives one from its name.
+        labelColor.isNotEmpty() -> labelColor
+        // A draft carries DRAFT_ID (""), so there is no identity to derive from yet.
+        // Staying white until the note exists costs one colour change at save time;
+        // hashing the empty string instead would give EVERY draft the same tint and
+        // then change it anyway, which is two surprises where one will do.
+        id.isEmpty() -> "default"
+        else -> derivedTint(id)
+    }
+
+/**
+ * Whether a note's colour was CHOSEN rather than derived — which is what decides
+ * between the two weights the card is drawn at.
+ *
+ * A tag (or, until step 5, the picker) means somebody said what this note is. A
+ * derived tint only means the board should not be a wall of white. Drawing both at
+ * the same weight is what prompted the operator's "the tints look the same as the
+ * chosen colors" — the tint was never meant to shout as loudly as a decision.
+ */
+fun noteColorIsChosen(
+    color: String,
+    labelColor: String,
+    known: Set<String>,
+): Boolean = labelColor.isNotEmpty() || (color.isNotEmpty() && color != "default" && color in known)
+
+// ---------------------------------------------------------------------------
+// The fill for an UNTAGGED note, which is a different job from the palette above.
+//
+// The palette has nine keys and they MEAN something: a tag's colour. An untagged
+// note's fill means nothing at all — it exists so a board is not a monolithic wall.
+// Tying the second job to the first was the mistake. Nine keys is far too few for a
+// board of any size, and once the nine were subdued enough not to shout they became
+// indistinguishable from each other: measured, the nine dark fills were separated by
+// at most a 1.03 contrast ratio, which is to say not at all. Nine tints that look
+// like three is exactly the wall the tint was added to break up.
+//
+// So this hashes to a colour directly rather than to a key. 338 distinct fills in
+// dark, 193 in light, against nine.
+//
+// TWO AXES, AND THE SECOND ONE IS THE FIX. The old ramp varied hue while pinning
+// every fill to the same lightness — deliberately, so each would read as a card
+// against the board. But the eye separates by lightness first, so nine hues at one
+// lightness read as one card repeated. Varying lightness too is what makes the
+// difference; the hue alone never could at this darkness.
+//
+// It is only SAFE to vary lightness because the card now has a grey edge of its own
+// (see NoteCard.CARD_EDGE_DARK). While the fill was the only boundary the card had,
+// it could not afford to drift toward the board. The edge bought that freedom.
+
+/** Lightness steps a derived fill can land on. Six rather than three because the
+ *  levels are what carry the variety, and rather than twelve because past a point
+ *  they stop being distinguishable and only cost contrast headroom. */
+private const val TINT_LEVELS = 6
+
+/**
+ * Saturation is FIXED, and that is what keeps this subtle no matter which hue it
+ * lands on. Variety comes from hue and lightness; loudness would come from
+ * saturation, so saturation is the one dial the hash never touches.
+ */
+private const val DARK_SATURATION = 0.25
+private const val LIGHT_SATURATION = 0.60
+
+/**
+ * HSL LIGHTNESS IS NOT LUMINANCE, and the floor here is set by the difference.
+ *
+ * The obvious floor is `neutral-900`'s own lightness, 0.090 — "start at the plain card
+ * surface and climb, so no note ever recedes into the board". That was the first
+ * attempt and it was wrong, because at a FIXED HSL lightness the eye sees wildly
+ * different brightnesses depending on hue: green carries 71% of the luminance formula
+ * and blue only 7%, so at L=0.090 a yellow measures 0.0118 and a blue 0.0061 — the
+ * blue landing 1.41x DARKER than the card it was supposed to match. A sixth of the
+ * board would have been holes rather than variety.
+ *
+ * 0.113 is the lowest floor at which EVERY hue clears the card surface, solved for
+ * rather than guessed. The range then measures 1.11–1.71 against the board where the
+ * old single level managed 1.14, so the floor is unchanged and the ceiling is much
+ * higher. `no generated fill sinks below the card surface` in DerivedTintTest is what
+ * caught the original mistake and what holds this.
+ */
+private val DARK_LIGHTNESS = doubleArrayOf(0.113, 0.127, 0.141, 0.155, 0.169, 0.183)
+
+/**
+ * Light runs the other way, from white down toward the `neutral-50` board and just
+ * past it. A card slightly darker than the board still reads as a card because the
+ * edge says so — the same freedom the edge bought in dark, spent in the other
+ * direction.
+ */
+private val LIGHT_LIGHTNESS = doubleArrayOf(1.000, 0.990, 0.980, 0.970, 0.960, 0.950)
+
+private const val HUE_DEGREES = 360L
+private const val LEVEL_BIT_SHIFT = 16
+private const val HUE_SECTOR_DEGREES = 60.0
+private const val TWO = 2.0
+private const val CHANNEL_MAX = 255.0
+private const val ROUND_HALF = 0.5
+private const val CHANNEL_CEILING = 255
+private const val ALPHA_OPAQUE = 0xFF
+private const val ALPHA_BIT_SHIFT = 24
+private const val RED_BIT_SHIFT = 16
+private const val GREEN_BIT_SHIFT = 8
+
+/**
+ * The opaque ARGB fill an untagged note wears, stable for the life of the note.
+ *
+ * Returns an Int rather than a Compose `Color` on purpose: this file stays free of
+ * `androidx.compose` so `DerivedTintTest` can run on the host JVM, and that test is
+ * the only mechanical guard the mirror with colors.ts has.
+ *
+ * Hue and level are read from DIFFERENT parts of the hash so a note's shade is not a
+ * function of its hue — two notes of nearly the same hue should still be able to
+ * differ in weight, which is half of where the variety comes from.
+ */
+fun derivedFillArgb(
+    id: String,
+    dark: Boolean,
+): Int {
+    val hash = tintHash(id).toLong() and UNSIGNED_MASK
+    val level = ((hash shr LEVEL_BIT_SHIFT) % TINT_LEVELS).toInt()
+    return hslToArgb(
+        hue = (hash % HUE_DEGREES).toDouble(),
+        saturation = if (dark) DARK_SATURATION else LIGHT_SATURATION,
+        lightness = if (dark) DARK_LIGHTNESS[level] else LIGHT_LIGHTNESS[level],
+    )
+}
+
+/**
+ * Textbook HSL to RGB, written out rather than pulled from a library because the
+ * TypeScript side has to compute the same bytes and there is no library both can
+ * share.
+ *
+ * DOUBLE, NOT FLOAT, and that is not a style choice. JavaScript has one number type
+ * and it is IEEE-754 binary64; a Kotlin `Float` is binary32, so the two would round
+ * differently near a channel boundary and a note would be one byte off between the
+ * phone and the browser. Nobody would ever see that as a bug — they would see two
+ * colours that are "sort of the same" and never work out why. Doubles on both sides
+ * make it the same arithmetic rather than nearly the same.
+ *
+ * Rounding is `floor(v + 0.5)` on both sides, NOT the language's `round`: Kotlin
+ * rounds half away from zero and JavaScript rounds half up, which agree for the
+ * non-negative values here, but stating the rule leaves nothing to have to check.
+ */
+private fun hslToArgb(
+    hue: Double,
+    saturation: Double,
+    lightness: Double,
+): Int {
+    val chroma = (1.0 - abs(TWO * lightness - 1.0)) * saturation
+    val sector = hue / HUE_SECTOR_DEGREES
+    val second = chroma * (1.0 - abs(sector % TWO - 1.0))
+    val match = lightness - chroma / TWO
+    // The six hue sectors, as a table rather than a `when` — which is also the form
+    // colors.ts uses, so the two read as the same function rather than as two people's
+    // idea of it. `sector` is in [0, 6) because the hue it came from is in [0, 360).
+    val ramps =
+        listOf(
+            Triple(chroma, second, 0.0),
+            Triple(second, chroma, 0.0),
+            Triple(0.0, chroma, second),
+            Triple(0.0, second, chroma),
+            Triple(second, 0.0, chroma),
+            Triple(chroma, 0.0, second),
+        )
+    val (red, green, blue) = ramps[sector.toInt()]
+    return (ALPHA_OPAQUE shl ALPHA_BIT_SHIFT) or
+        (channelByte(red + match) shl RED_BIT_SHIFT) or
+        (channelByte(green + match) shl GREEN_BIT_SHIFT) or
+        channelByte(blue + match)
+}
+
+private fun channelByte(value: Double): Int = (value * CHANNEL_MAX + ROUND_HALF).toInt().coerceIn(0, CHANNEL_CEILING)

android/app/src/main/java/com/fabledsword/thoughtsync/ui/EditorAction.kt

@@ -29,15 +29,6 @@ sealed interface EditorAction {
         val color: String,
     ) : EditorAction
 
-    /**
-     * Give this note a checklist.
-     *
-     * Not a conversion — a note HAS a checklist rather than BEING one (M13 step 2),
-     * so nothing moves and nothing is swapped: the body stays exactly where it is and
-     * the note gains a first, empty item for someone to type into.
-     */
-    data object AddChecklist : EditorAction
-
     data class SetPinned(
         val pinned: Boolean,
     ) : EditorAction
@@ -52,23 +43,12 @@ sealed interface EditorAction {
 
     data object DeleteForever : EditorAction
 
-    data class AddItem(
-        val text: String,
-    ) : EditorAction
-
-    data class SetItemChecked(
-        val itemId: String,
-        val checked: Boolean,
-    ) : EditorAction
-
-    data class SetItemText(
-        val itemId: String,
-        val text: String,
-    ) : EditorAction
-
-    data class DeleteItem(
-        val itemId: String,
-    ) : EditorAction
+    // No checklist actions at all any more (M304). An item is a `- [ ] ` line of the
+    // body, so adding, renaming, ticking or deleting one is editing text — which the
+    // editor already does, through SaveText, with the same autosave and the same
+    // revision window as any other edit. Routing them through the store would have
+    // meant the store handing back a note whose body disagreed with the field the
+    // person was typing in.
 
     /**
      * The note's MANUAL labels, replacing whatever was there.

android/app/src/main/java/com/fabledsword/thoughtsync/ui/EditorBlock.kt

@@ -0,0 +1,155 @@
+package com.fabledsword.thoughtsync.ui
+
+import androidx.compose.runtime.saveable.Saver
+import androidx.compose.ui.text.TextRange
+import androidx.compose.ui.text.input.TextFieldValue
+import com.fabledsword.thoughtsync.core.checklistItems
+import com.fabledsword.thoughtsync.core.checklistRender
+
+/**
+ * One piece of a note body, as the editor DRAWS it.
+ *
+ * The note is still one markdown string underneath (M304) — this is a rendering and
+ * input shape, and nothing below the editor can tell it exists. [joinBlocks] puts the
+ * string back together on every edit.
+ *
+ * A run of prose lines is ONE block rather than one per line. Typing a paragraph has
+ * to feel like typing a paragraph, and a separate field under every sentence would
+ * break the caret in the middle of writing. Only a checklist item earns a block of its
+ * own, because only a checklist item needs a widget.
+ *
+ * The block owns its [TextFieldValue], not just its text, so a caret survives an edit
+ * to some other block. And [id] is stable across edits: Compose keys fields by
+ * position unless told otherwise, so inserting an item above one would otherwise move
+ * everyone's caret up a row. Content cannot serve as that key — two empty items are
+ * identical and neither is the other.
+ */
+data class EditorBlock(
+    val id: Long,
+    val value: TextFieldValue,
+    /** null for prose; ticked-or-not for a checklist item. */
+    val checked: Boolean?,
+) {
+    val isTask: Boolean get() = checked != null
+}
+
+/**
+ * Split a body into blocks, numbering them from [firstId].
+ *
+ * Which lines are items comes from the core, not from a pattern here — the grammar is
+ * written three times already and Kotlin is not going to be the fourth.
+ */
+fun splitBlocks(
+    body: String,
+    firstId: Long = 0,
+): List<EditorBlock> {
+    val itemAt = checklistItems(body).associateBy { it.line.toInt() }
+    val out = mutableListOf<EditorBlock>()
+    val prose = mutableListOf<String>()
+    var id = firstId
+
+    fun flushProse() {
+        if (prose.isNotEmpty()) {
+            out += EditorBlock(id++, TextFieldValue(prose.joinToString("\n")), null)
+            prose.clear()
+        }
+    }
+
+    body.split("\n").forEachIndexed { n, line ->
+        val item = itemAt[n]
+        if (item == null) {
+            prose += line
+        } else {
+            flushProse()
+            out += EditorBlock(id++, TextFieldValue(item.text), item.checked)
+        }
+    }
+    flushProse()
+
+    // Never empty: an empty note still needs one field to type into.
+    return out.ifEmpty { listOf(EditorBlock(id, TextFieldValue(""), null)) }
+}
+
+/**
+ * The body those blocks stand for — byte-identical to what [splitBlocks] was given,
+ * for a body already in canonical form. A non-canonical one (`- [X]`, an odd bullet)
+ * comes back canonical, which is the same rule every other rewriter in `derive`
+ * follows.
+ */
+fun joinBlocks(blocks: List<EditorBlock>): String =
+    blocks.joinToString("\n") { block ->
+        val checked = block.checked
+        if (checked == null) block.value.text else checklistRender(block.value.text, checked)
+    }
+
+/**
+ * Rotation carries the TEXT and re-derives the shape.
+ *
+ * Blocks are not parcelable and their ids are meaningless across a process death, so
+ * the body string is the honest thing to save — it is the real state, and everything
+ * else about a block is derived from it.
+ */
+val blocksSaver: Saver<List<EditorBlock>, String> =
+    Saver(save = { joinBlocks(it) }, restore = { splitBlocks(it) })
+
+/**
+ * What the return key does on a checklist item.
+ *
+ * `internal` rather than private because BlockBody.kt calls it. These three helpers
+ * are the block MODEL and the composables are the block UI — one file was doing both,
+ * which detekt noticed by counting functions before anybody noticed by reading.
+ *
+ * On one with words in it, a new empty item below. On an EMPTY one, the item becomes
+ * prose — which is how a list ENDS, and the same rule the plain text field used
+ * before this: without it a list is impossible to get out of.
+ *
+ * Deliberately appends rather than splitting at the caret. Splitting an item in two is
+ * a rarity, and the caret is at the end for every ordinary use of this key.
+ */
+internal fun afterEnter(
+    blocks: List<EditorBlock>,
+    index: Int,
+    newId: Long,
+): List<EditorBlock> {
+    val block = blocks[index]
+    val out = blocks.toMutableList()
+    if (block.value.text.isBlank()) {
+        out[index] = block.copy(value = TextFieldValue(""), checked = null)
+    } else {
+        out.add(index + 1, EditorBlock(newId, TextFieldValue(""), false))
+    }
+    return out
+}
+
+/** Drop a block, leaving at least one field to type into. */
+internal fun List<EditorBlock>.withoutIndex(index: Int): List<EditorBlock> {
+    val out = toMutableList().also { it.removeAt(index) }
+    return out.ifEmpty { listOf(EditorBlock(nextId(), TextFieldValue(""), null)) }
+}
+
+/** An id nothing else is using. Monotonic within a session, which is all it has to be. */
+internal fun List<EditorBlock>.nextId(): Long = (maxOfOrNull { it.id } ?: -1L) + 1L
+
+/**
+ * One more empty checklist item at the end, and the id to put the caret in.
+ *
+ * What the toolbar's checklist button does. It appends rather than inserting at the
+ * caret because a block editor has no single caret to insert at — the field that had
+ * focus may not even be the one being looked at by the time this runs.
+ */
+fun List<EditorBlock>.plusTask(): Pair<List<EditorBlock>, Long> {
+    val id = nextId()
+    return (this + EditorBlock(id, TextFieldValue(""), false)) to id
+}
+
+/**
+ * Put the caret at the end of the last block, for an editor that has just opened.
+ *
+ * Opening an existing note means continuing it, and a caret at offset zero would put
+ * the cursor before the first character of the wrong field.
+ */
+fun List<EditorBlock>.focusedAtEnd(): List<EditorBlock> {
+    if (isEmpty()) return this
+    val last = last()
+    return dropLast(1) + last.copy(value = last.value.copy(selection = TextRange(last.value.text.length)))
+}

android/app/src/main/java/com/fabledsword/thoughtsync/ui/EditorChecklist.kt

@@ -1,144 +0,0 @@
-package com.fabledsword.thoughtsync.ui
-
-import androidx.compose.foundation.layout.Column
-import androidx.compose.foundation.layout.Row
-import androidx.compose.foundation.layout.padding
-import androidx.compose.foundation.text.KeyboardActions
-import androidx.compose.foundation.text.KeyboardOptions
-import androidx.compose.material.icons.Icons
-import androidx.compose.material.icons.filled.Add
-import androidx.compose.material.icons.filled.Close
-import androidx.compose.material3.Checkbox
-import androidx.compose.material3.Icon
-import androidx.compose.material3.IconButton
-import androidx.compose.material3.MaterialTheme
-import androidx.compose.runtime.Composable
-import androidx.compose.runtime.getValue
-import androidx.compose.runtime.mutableStateOf
-import androidx.compose.runtime.remember
-import androidx.compose.runtime.setValue
-import androidx.compose.ui.Alignment
-import androidx.compose.ui.Modifier
-import androidx.compose.ui.focus.onFocusChanged
-import androidx.compose.ui.res.stringResource
-import androidx.compose.ui.text.input.ImeAction
-import androidx.compose.ui.text.style.TextDecoration
-import androidx.compose.ui.unit.dp
-import com.fabledsword.thoughtsync.R
-import com.fabledsword.thoughtsync.core.ChecklistItem
-import com.fabledsword.thoughtsync.core.Note
-
-/**
- * The checklist, with real checkboxes this time.
- *
- * The card renders glyphs because it is a preview; here every row is live. This is
- * the other half of the answer to how a list gets typed on a phone: the capture
- * sheet takes a whole list at once, one item per line, because at capture time the
- * list is already in your head and a tap per row would be the slow part. The
- * editor is where a list is REVISED, and revising is item-at-a-time — so this is
- * where the per-row control lives.
- *
- * No empty state: a checklist with no items already shows the add row with its
- * hint, which says the same thing an empty state would and can be typed into.
- */
-@Composable
-fun ChecklistEditor(
-    note: Note,
-    readOnly: Boolean,
-    onAction: (EditorAction) -> Unit,
-) {
-    Column {
-        note.items.forEach { item ->
-            ChecklistRow(item = item, readOnly = readOnly, onAction = onAction)
-        }
-        if (!readOnly) {
-            AddItemRow(onAdd = { onAction(EditorAction.AddItem(it)) })
-        }
-    }
-}
-
-/**
- * One row: a live checkbox, editable text, and a remove button.
- *
- * The text commits on FOCUS LOSS rather than per keystroke. Every commit is a
- * store write that reloads the note, so per-keystroke saving would both hammer
- * SQLite and race the reload against the next character.
- */
-@Composable
-private fun ChecklistRow(
-    item: ChecklistItem,
-    readOnly: Boolean,
-    onAction: (EditorAction) -> Unit,
-) {
-    // Keyed by item id, so a reload after some OTHER row's edit doesn't reset the
-    // text being typed here.
-    var text by remember(item.id) { mutableStateOf(item.text) }
-    val commit = { if (text != item.text) onAction(EditorAction.SetItemText(item.id, text)) }
-
-    Row(verticalAlignment = Alignment.CenterVertically) {
-        Checkbox(
-            checked = item.checked,
-            onCheckedChange = { onAction(EditorAction.SetItemChecked(item.id, it)) },
-            enabled = !readOnly,
-        )
-        PlainTextField(
-            value = text,
-            onValueChange = { text = it },
-            modifier =
-                Modifier
-                    .weight(1f)
-                    .onFocusChanged { if (!it.isFocused) commit() },
-            enabled = !readOnly,
-            singleLine = true,
-            textStyle =
-                MaterialTheme.typography.bodyLarge.copy(
-                    // Struck through when done, matching the card and the web.
-                    textDecoration = if (item.checked) TextDecoration.LineThrough else null,
-                ),
-            keyboardOptions = KeyboardOptions(imeAction = ImeAction.Done),
-            keyboardActions = KeyboardActions(onDone = { commit() }),
-        )
-        if (!readOnly) {
-            IconButton(onClick = { onAction(EditorAction.DeleteItem(item.id)) }) {
-                Icon(
-                    Icons.Filled.Close,
-                    contentDescription = stringResource(R.string.editor_remove_item),
-                )
-            }
-        }
-    }
-}
-
-/**
- * The always-present row at the bottom for adding an item.
- *
- * It clears but keeps focus after a submit, so a list can be typed straight
- * through — "milk ⏎ eggs ⏎ bread" — rather than costing a tap between each. That
- * is the same speed the capture sheet's one-item-per-line field buys, carried into
- * the editor so refining a list never feels slower than making one.
- */
-@Composable
-private fun AddItemRow(onAdd: (String) -> Unit) {
-    var text by remember { mutableStateOf("") }
-    Row(verticalAlignment = Alignment.CenterVertically) {
-        Icon(
-            Icons.Filled.Add,
-            contentDescription = null,
-            modifier = Modifier.padding(horizontal = 12.dp),
-            tint = MaterialTheme.colorScheme.onSurfaceVariant,
-        )
-        PlainTextField(
-            value = text,
-            onValueChange = { text = it },
-            modifier = Modifier.weight(1f),
-            hint = R.string.editor_add_item,
-            singleLine = true,
-            keyboardOptions = KeyboardOptions(imeAction = ImeAction.Done),
-            keyboardActions =
-                KeyboardActions(onDone = {
-                    onAdd(text)
-                    text = ""
-                }),
-        )
-    }
-}

android/app/src/main/java/com/fabledsword/thoughtsync/ui/EditorChrome.kt

@@ -1,5 +1,6 @@
 package com.fabledsword.thoughtsync.ui
 
+import android.text.format.DateUtils
 import androidx.annotation.StringRes
 import androidx.compose.foundation.background
 import androidx.compose.foundation.border
@@ -8,23 +9,31 @@ import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.imePadding
+import androidx.compose.foundation.layout.navigationBarsPadding
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.shape.CircleShape
 import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.ArrowBack
 import androidx.compose.material.icons.automirrored.filled.List
+import androidx.compose.material.icons.filled.Check
 import androidx.compose.material.icons.filled.Close
 import androidx.compose.material.icons.filled.MoreVert
 import androidx.compose.material.icons.filled.Notifications
-import androidx.compose.material3.BottomAppBar
 import androidx.compose.material3.DropdownMenu
 import androidx.compose.material3.DropdownMenuItem
 import androidx.compose.material3.ExperimentalMaterial3Api
+import androidx.compose.material3.FilledTonalIconButton
 import androidx.compose.material3.Icon
 import androidx.compose.material3.IconButton
+import androidx.compose.material3.IconButtonDefaults
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.material3.TextButton
+import androidx.compose.material3.TopAppBar
+import androidx.compose.material3.TopAppBarDefaults
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
@@ -39,7 +48,19 @@ import com.fabledsword.thoughtsync.R
 import com.fabledsword.thoughtsync.core.Note
 
 /**
- * The editor's action bar, at the bottom where a thumb already is.
+ * The editor's action bar, along the top of the surface.
+ *
+ * It sits exactly where the capture sheet's drag handle used to. The handle cost
+ * this strip of screen and did nothing that a back gesture does not already do, so
+ * the strip carries the actions instead.
+ *
+ * Top rather than bottom, now that this one surface is used for WRITING as well as
+ * editing: the keyboard owns the bottom of the display for most of a note's life,
+ * so a bar down there spends its time riding on the IME. That is the right place
+ * for a send button and the wrong one for a colour picker, which is reached for
+ * between thoughts rather than at the end of them. The cost is honest — the top of
+ * a phone is further from a thumb than the bottom — and it buys a bar that does not
+ * move while you type.
  *
  * The three affordances with a permanent slot are the ones reached for while still
  * writing — colour, reminder, note-or-list. Everything structural (pin, labels,
@@ -54,16 +75,31 @@ import com.fabledsword.thoughtsync.core.Note
  */
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
-fun EditorBottomBar(
+fun EditorTopBar(
     note: Note,
     readOnly: Boolean,
     tint: NoteTint,
+    onClose: () -> Unit,
+    onStartChecklist: () -> Unit,
     onPicker: (Picker) -> Unit,
     onConfirmDelete: () -> Unit,
     onAction: (EditorAction) -> Unit,
 ) {
     val dark = isSystemInDarkTheme()
-    BottomAppBar(containerColor = tint.background(dark)) {
+    TopAppBar(
+        title = {},
+        navigationIcon = {
+            // The only way out, and the only thing that needed a "save" button
+            // before writes became continuous. Leaving IS saving now, which is what
+            // the line in the bottom corner is there to say out loud.
+            IconButton(onClick = onClose) {
+                Icon(
+                    Icons.AutoMirrored.Filled.ArrowBack,
+                    contentDescription = stringResource(R.string.editor_back),
+                )
+            }
+        },
+        actions = {
             if (!readOnly) {
                 // A dot in the note's CURRENT colour rather than a palette icon: it
                 // shows what the colour is as well as what the button does.
@@ -83,21 +119,17 @@ fun EditorBottomBar(
                         contentDescription = stringResource(R.string.editor_reminder),
                     )
                 }
-            // Adds the first checklist item, which is what makes the checklist
-            // editor appear. Hidden once the note already has one — there is nothing
-            // left to add that the checklist's own "+" row doesn't do better.
-            if (note.items.isEmpty()) {
-                IconButton(onClick = { onAction(EditorAction.AddChecklist) }) {
+                // Inserts `- [ ] ` at the caret. Always available, and never hidden:
+                // a checklist is text now (M304), so there is no section to be
+                // already-showing and no reason a second list cannot start further
+                // down the same note.
+                IconButton(onClick = onStartChecklist) {
                     Icon(
                         Icons.AutoMirrored.Filled.List,
                         contentDescription = stringResource(R.string.editor_add_checklist),
                     )
                 }
             }
-        }
-
-        Box(modifier = Modifier.weight(1f))
-
             OverflowMenu(
                 note = note,
                 readOnly = readOnly,
@@ -105,6 +137,127 @@ fun EditorBottomBar(
                 onConfirmDelete = onConfirmDelete,
                 onAction = onAction,
             )
+        },
+        // EXPLICIT, and not optional — the same lesson the old bottom bar learned.
+        // Material derives a bar's content colour from its container via
+        // contentColorFor(), which maps a colour-SCHEME ROLE to its `on-` pair and
+        // returns Unspecified for anything else. A note tint is never a role, so the
+        // icons drew with no colour filter: black vectors on a near-black bar, a
+        // toolbar that rendered the whole time and was invisible in dark mode.
+        //
+        // onSurface for the actions too, not the default onSurfaceVariant: these sit
+        // on a tinted bar rather than a scheme surface, and the muted variant does
+        // not have the contrast to spare.
+        colors =
+            TopAppBarDefaults.topAppBarColors(
+                containerColor = tint.background(dark),
+                navigationIconContentColor = MaterialTheme.colorScheme.onSurface,
+                titleContentColor = MaterialTheme.colorScheme.onSurface,
+                actionIconContentColor = MaterialTheme.colorScheme.onSurface,
+            ),
+    )
+}
+
+/**
+ * The footer: when the note was last written, and the way out.
+ *
+ * **Where the note stands.** There is no save button, and there should not be — a
+ * note is saved continuously, so a button offering to do what already happened is a
+ * lie with a tap attached. But that left nothing on screen saying the work is safe,
+ * and "closing this keeps it" is not a thing anyone should have to be told twice. So
+ * the state says it, as a fact rather than an instruction: Not saved yet → Saving… →
+ * Edited just now is the whole lifecycle, and someone who watches it once never has
+ * to wonder again.
+ *
+ * **The way out.** Down here because of where hands are. Moving the toolbar to the
+ * top took the back arrow with it, which left the only exit from a full-screen
+ * editor in the top-left corner — the furthest point on the display from a
+ * right-handed thumb, and reached over the whole note to get to. The operator hit
+ * that on the first device pass and was right to. So the exit lives in the bottom
+ * corner, which with the keyboard up sits directly above it.
+ *
+ * The top-left arrow stays as well. Two affordances for one action is usually
+ * clutter, but this is the case that earns it: the arrow is what habit, the system
+ * back gesture and TalkBack all expect of a full-screen surface, and removing it
+ * would strand the reflex to strike a duplicate that costs one icon slot.
+ *
+ * A checkmark, at the operator's ask. I had shipped the word "Done" here on the
+ * argument that a tick in a NOTES app reads as a checklist item; overruled, and the
+ * filled treatment is what settles it — a tonal button in the note's own colour is
+ * plainly a control, where a bare glyph beside a checklist would not be. It carries
+ * "Done" as its content description, so the reasoning survives where it actually
+ * mattered: read aloud.
+ *
+ * [DateUtils] rather than a hand-rolled formatter: it is localised, it already
+ * knows the difference between minutes, hours and yesterday, and getting plurals
+ * right in every language is not this app's problem to solve twice.
+ */
+@Composable
+fun EditorFooter(
+    updatedAt: String?,
+    saving: Boolean,
+    tint: NoteTint,
+    onClose: () -> Unit,
+    modifier: Modifier = Modifier,
+) {
+    val dark = isSystemInDarkTheme()
+    Row(
+        modifier =
+            modifier
+                .fillMaxWidth()
+                // Rides above the keyboard, like the bar that used to be here. The
+                // content Column deliberately does not also inset for the IME:
+                // Scaffold measures this row at its lifted height and passes the
+                // inset down.
+                .imePadding()
+                .navigationBarsPadding()
+                .padding(horizontal = 12.dp, vertical = 4.dp),
+        // The gap is what keeps the timestamp from reading as the button's label.
+        horizontalArrangement = Arrangement.spacedBy(12.dp, Alignment.End),
+        verticalAlignment = Alignment.CenterVertically,
+    ) {
+        Text(
+            text = savedLabel(updatedAt, saving),
+            style = MaterialTheme.typography.labelSmall,
+            color = MaterialTheme.colorScheme.onSurfaceVariant,
+        )
+        FilledTonalIconButton(
+            onClick = onClose,
+            // The note's own colour rather than the scheme's secondaryContainer,
+            // which would be the one element on a tinted card ignoring the tint.
+            colors =
+                IconButtonDefaults.filledTonalIconButtonColors(
+                    containerColor = tint.chipBackground(dark),
+                    contentColor = tint.chipForeground(dark),
+                ),
+        ) {
+            Icon(Icons.Filled.Check, contentDescription = stringResource(R.string.editor_done))
+        }
+    }
+}
+
+/** The three things the footer can be saying, in the order it says them. */
+@Composable
+private fun savedLabel(
+    updatedAt: String?,
+    saving: Boolean,
+): String {
+    // No timestamp means no row yet — a draft opened by + and not typed into.
+    val at = updatedAt?.let { epochMillis(it) }
+    val now = System.currentTimeMillis()
+    return when {
+        saving -> stringResource(R.string.editor_saving)
+        at == null -> stringResource(R.string.editor_unsaved)
+        // DateUtils rounds anything under its minimum resolution to "0 minutes
+        // ago" — which is both odd-looking and precisely the moment this line is
+        // on screen for, since it is the moment right after a save lands.
+        now - at < DateUtils.MINUTE_IN_MILLIS ->
+            stringResource(R.string.editor_edited, stringResource(R.string.editor_just_now))
+        else ->
+            stringResource(
+                R.string.editor_edited,
+                DateUtils.getRelativeTimeSpanString(at, now, DateUtils.MINUTE_IN_MILLIS).toString(),
+            )
     }
 }
 
@@ -177,7 +330,7 @@ fun EditorLabelRow(
     val dark = isSystemInDarkTheme()
     Column(modifier = Modifier.padding(top = 12.dp)) {
         note.labels.forEach { label ->
-            val tint = noteTint(label.color)
+            val tint = labelTintFor(label.name, label.color)
             Row(
                 verticalAlignment = Alignment.CenterVertically,
                 modifier = Modifier.padding(vertical = 2.dp),
@@ -190,6 +343,7 @@ fun EditorLabelRow(
                         Modifier
                             .clip(CircleShape)
                             .background(tint.chipBackground(dark))
+                            .border(1.dp, tint.chipBorder(dark), CircleShape)
                             .padding(horizontal = 10.dp, vertical = 4.dp),
                 )
                 if (label.viaTag) {

android/app/src/main/java/com/fabledsword/thoughtsync/ui/NoteCard.kt

@@ -15,59 +15,73 @@ import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.remember
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.clip
-import androidx.compose.ui.res.pluralStringResource
+import androidx.compose.ui.draw.shadow
+import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.font.FontStyle
 import androidx.compose.ui.text.style.TextDecoration
 import androidx.compose.ui.text.style.TextOverflow
 import androidx.compose.ui.unit.dp
 import com.fabledsword.thoughtsync.R
-import com.fabledsword.thoughtsync.core.ChecklistItem
+import com.fabledsword.thoughtsync.core.BodyItem
 import com.fabledsword.thoughtsync.core.Note
 import com.fabledsword.thoughtsync.core.NoteLabel
+import com.fabledsword.thoughtsync.core.checklistItems
 
 @Composable
 fun NoteCard(
     note: Note,
     onOpen: () -> Unit,
+    onToggleItem: (Int, Boolean) -> Unit,
 ) {
     val dark = isSystemInDarkTheme()
-    val tint = noteTint(note.color)
 
     Column(
         modifier =
             Modifier
                 .fillMaxWidth()
+                // Depth, not the boundary — the edge below is that. 1dp: enough to
+                // separate a white card from a #fafafa board, and the web's own
+                // `shadow-sm` is the value it is matching.
+                .shadow(CARD_ELEVATION, RoundedCornerShape(CARD_RADIUS))
                 // Clipped BEFORE clickable, so the ripple is bounded by the card's
                 // rounded corners instead of a rectangle overhanging them.
                 .clip(RoundedCornerShape(CARD_RADIUS))
                 .clickable(onClickLabel = stringResource(R.string.board_open_note), onClick = onOpen)
-                .background(tint.background(dark))
-                .border(1.dp, tint.border(dark), RoundedCornerShape(CARD_RADIUS))
+                .background(noteCardColor(note, dark))
+                // ONE grey edge on every card, regardless of its colour — the tint is
+                // deliberately not consulted here. See CARD_EDGE_DARK.
+                .border(1.dp, if (dark) CARD_EDGE_DARK else CARD_EDGE_LIGHT, RoundedCornerShape(CARD_RADIUS))
                 .padding(12.dp),
     ) {
-        // Body then checklist, in order — a note can carry both (M13 step 2), and
-        // nothing above them: the first line of the body IS the note's name, at the
-        // same weight as the rest of it (M13 steps 3 and 4).
-        if (note.body.isNotBlank()) {
-            Text(
-                text = note.body,
-                style = MaterialTheme.typography.bodyMedium,
-                maxLines = MAX_PREVIEW_LINES,
-                overflow = TextOverflow.Ellipsis,
-            )
-        }
-        if (note.items.isNotEmpty()) {
-            if (note.body.isNotBlank()) Spacer(Modifier.height(4.dp))
-            Checklist(items = note.items)
+        // TAGS FIRST. They used to sit under everything else, which on a tall note put
+        // the one thing that says what a note IS below the fold of a glance. A board is
+        // scanned, not read, and the answer to "which of these is about the thing I am
+        // looking for" should be the first thing the eye lands on rather than the last.
+        //
+        // Above the body rather than beside it, because the body's first line is the
+        // note's NAME (M13 steps 3 and 4) and a chip floated next to it would compete
+        // with the thing that identifies the note. A row of its own costs one line and
+        // only on notes that have tags at all.
+        if (note.labels.isNotEmpty()) {
+            LabelChips(labels = note.labels)
+            Spacer(Modifier.height(8.dp))
         }
 
-        // A note with no body and no items still has to occupy the board legibly —
-        // otherwise it reads as a rendering bug.
-        if (note.body.isBlank() && note.items.isEmpty()) {
+        // Body then checklist, in order — a note can carry both (M13 step 2). The
+        // first line of the body IS the note's name, at the same weight as the rest of
+        // it (M13 steps 3 and 4).
+        if (note.body.isNotBlank()) {
+            NoteBody(note = note, onToggleItem = onToggleItem)
+        }
+
+        // A note with nothing in it still has to occupy the board legibly — otherwise
+        // it reads as a rendering bug.
+        if (note.body.isBlank()) {
             Text(
                 text = stringResource(R.string.board_empty_note),
                 style = MaterialTheme.typography.bodyMedium,
@@ -76,11 +90,6 @@ fun NoteCard(
             )
         }
 
-        if (note.labels.isNotEmpty()) {
-            Spacer(Modifier.height(8.dp))
-            LabelChips(labels = note.labels)
-        }
-
         note.remindAt?.let { at ->
             Spacer(Modifier.height(8.dp))
             ReminderChip(instant = at, recurrence = note.recurrence)
@@ -88,18 +97,83 @@ fun NoteCard(
     }
 }
 
+/**
+ * The note's body, with its checklist drawn where it actually sits.
+ *
+ * Rendered line by line rather than as one block of text, because an item is a line
+ * of the body now (M304) and a card that showed the prose and then the list would put
+ * every list in the wrong place — and, since the body already contains those lines,
+ * would show each one twice.
+ *
+ * Which lines are items is asked of the core rather than matched here. The grammar is
+ * already written three times; a fourth in Compose would be a fourth place for a
+ * checklist to change shape when it syncs.
+ */
 @Composable
-private fun Checklist(items: List<ChecklistItem>) {
+private fun NoteBody(
+    note: Note,
+    onToggleItem: (Int, Boolean) -> Unit,
+) {
+    val lines = remember(note.body) { note.body.split("\n") }
+    // Read from the BODY rather than from note.items, which is the same list by a
+    // longer route — and one that can lag the text by a save.
+    val itemAtLine =
+        remember(note.body) {
+            checklistItems(note.body)
+                .mapIndexed { index, item -> item.line.toInt() to (index to item) }
+                .toMap()
+        }
+
     Column(verticalArrangement = Arrangement.spacedBy(2.dp)) {
-        items.take(MAX_CHECKLIST_ROWS).forEach { item ->
+        lines.take(MAX_PREVIEW_LINES).forEachIndexed { n, line ->
+            val found = itemAtLine[n]
+            when {
+                found != null ->
+                    ChecklistRow(found.second) { onToggleItem(found.first, !found.second.checked) }
+                // Kept as a gap rather than dropped: it is the paragraph break
+                // somebody typed, and the card reads as a wall without it.
+                line.isBlank() -> Spacer(Modifier.height(4.dp))
+                else ->
+                    Text(
+                        text = line,
+                        style = MaterialTheme.typography.bodyMedium,
+                        maxLines = MAX_WRAPPED_LINES,
+                        overflow = TextOverflow.Ellipsis,
+                    )
+            }
+        }
+        if (lines.size > MAX_PREVIEW_LINES) {
+            Text(
+                text = "…",
+                style = MaterialTheme.typography.bodyMedium,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+            )
+        }
+    }
+}
+
+/**
+ * One checklist row on a card, with a box you can actually tick.
+ *
+ * A glyph rather than a Material Checkbox: it sits on a line of text and has to share
+ * that line's metrics, and a real Checkbox brings 48dp of touch target that would
+ * space a list out like a form. The tap target is the glyph's own padding, which is
+ * why it carries `clickable` rather than the row — clicking the TEXT should open the
+ * note, the way clicking anywhere else on the card does.
+ */
+@Composable
+private fun ChecklistRow(
+    item: BodyItem,
+    onToggle: () -> Unit,
+) {
     Row(verticalAlignment = Alignment.Top) {
-                // A glyph rather than a real Checkbox: the card is a PREVIEW, and
-                // a live control here would invite taps that the board cannot yet
-                // honour. It becomes interactive with the editor.
         Text(
             text = if (item.checked) "☑" else "☐",
             style = MaterialTheme.typography.bodyMedium,
-                    modifier = Modifier.padding(end = 6.dp),
+            modifier =
+                Modifier
+                    .clickable(onClick = onToggle)
+                    .padding(end = 6.dp),
         )
         Text(
             text = item.text,
@@ -111,21 +185,10 @@ private fun Checklist(items: List<ChecklistItem>) {
                 } else {
                     MaterialTheme.colorScheme.onSurface
                 },
-                    maxLines = 2,
+            maxLines = MAX_WRAPPED_LINES,
             overflow = TextOverflow.Ellipsis,
         )
     }
-        }
-        val hidden = items.size - MAX_CHECKLIST_ROWS
-        if (hidden > 0) {
-            Text(
-                text = pluralStringResource(R.plurals.board_more_items, hidden, hidden),
-                style = MaterialTheme.typography.labelMedium,
-                color = MaterialTheme.colorScheme.onSurfaceVariant,
-                modifier = Modifier.padding(top = 2.dp),
-            )
-        }
-    }
 }
 
 @Composable
@@ -135,7 +198,7 @@ private fun LabelChips(labels: List<NoteLabel>) {
     // not grow taller than its content. The editor shows the full set.
     Row(horizontalArrangement = Arrangement.spacedBy(4.dp)) {
         labels.take(MAX_LABEL_CHIPS).forEach { label ->
-            val tint = noteTint(label.color)
+            val tint = labelTintFor(label.name, label.color)
             Text(
                 text = label.name,
                 style = MaterialTheme.typography.labelSmall,
@@ -146,6 +209,7 @@ private fun LabelChips(labels: List<NoteLabel>) {
                     Modifier
                         .clip(RoundedCornerShape(CHIP_RADIUS))
                         .background(tint.chipBackground(dark))
+                        .border(1.dp, tint.chipBorder(dark), RoundedCornerShape(CHIP_RADIUS))
                         .padding(horizontal = 6.dp, vertical = 2.dp),
             )
         }
@@ -182,7 +246,36 @@ private fun ReminderChip(
 }
 
 private const val MAX_PREVIEW_LINES = 8
-private const val MAX_CHECKLIST_ROWS = 8
+
+/** How far one long line of a card may wrap before it is cut. */
+private const val MAX_WRAPPED_LINES = 2
 private const val MAX_LABEL_CHIPS = 3
 private val CARD_RADIUS = 12.dp
+private val CARD_ELEVATION = 1.dp
+
+// THE CARD'S EDGE — one grey, every card, both weights, all ten colour keys. It is a
+// constant here rather than a column in NoteTint precisely so the palette CANNOT vary
+// it; uniformity is the feature.
+//
+// The version of this that came from the palette was a `{hue}-900` border, and it
+// failed twice over: the line measured 1.56-2.09 against its own fill while the fill
+// managed only 1.03-1.05 against the board, so it was the loudest thing on the card —
+// and it carried the same information the fill did. A field of cards read as a grid of
+// outlines however different the colours inside were. A neutral line carries no
+// information at all, which is exactly what lets it be structure instead of content.
+//
+// The two values are MATCHED rather than chosen by eye: each measures ~1.6-1.7 against
+// the card it edges (light 1.57-1.98 across all twenty fills, dark 1.58-1.73), so the
+// edge reads with the same authority in either theme. Dark is `neutral-700`, which is
+// what the `default` card's border always was — one entry's value promoted to the rule
+// for all of them. Light sits between `neutral-300` and `neutral-400`, neither of which
+// lands in range: 300 fades to 1.18 on a gray-tagged card, 400 jumps to 2.52 and reads
+// as a wireframe.
+//
+// NOT a translucent black/white edge, which is the tidier way to write this and was
+// measured and rejected: a border composites over the card's own fill, so `White` at
+// 20% comes out #56396D on a purple card and #A3C9C1 on a teal one. Hue-coded edges are
+// the thing being removed.
+private val CARD_EDGE_LIGHT = Color(0xFFB8B8B8)
+private val CARD_EDGE_DARK = Color(0xFF404040)
 private val CHIP_RADIUS = 6.dp

android/app/src/main/java/com/fabledsword/thoughtsync/ui/NoteEditorScreen.kt

@@ -1,32 +1,30 @@
 package com.fabledsword.thoughtsync.ui
 
 import androidx.activity.compose.BackHandler
-import androidx.annotation.StringRes
 import androidx.compose.foundation.isSystemInDarkTheme
+import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.WindowInsets
 import androidx.compose.foundation.layout.fillMaxSize
-import androidx.compose.foundation.layout.fillMaxWidth
-import androidx.compose.foundation.layout.imePadding
 import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.statusBars
+import androidx.compose.foundation.layout.windowInsetsPadding
 import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.foundation.verticalScroll
-import androidx.compose.material.icons.Icons
-import androidx.compose.material.icons.automirrored.filled.ArrowBack
 import androidx.compose.material3.AlertDialog
 import androidx.compose.material3.ExperimentalMaterial3Api
-import androidx.compose.material3.Icon
-import androidx.compose.material3.IconButton
-import androidx.compose.material3.LinearProgressIndicator
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Scaffold
+import androidx.compose.material3.Surface
 import androidx.compose.material3.Text
 import androidx.compose.material3.TextButton
-import androidx.compose.material3.TopAppBar
-import androidx.compose.material3.TopAppBarDefaults
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
+import androidx.compose.runtime.saveable.rememberSaveable
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.res.stringResource
@@ -34,36 +32,63 @@ import androidx.compose.ui.unit.dp
 import com.fabledsword.thoughtsync.R
 import com.fabledsword.thoughtsync.core.Label
 import com.fabledsword.thoughtsync.core.Note
+import kotlinx.coroutines.delay
 
 /**
- * The note editor: a full screen, not a sheet.
+ * The one writing surface: a new note and an existing one are the same screen.
  *
- * A sheet works for capture, where the board behind it is reassurance that the
- * thought landed somewhere. Editing is different — a sustained task with the
- * keyboard up — and a sheet would spend the whole time fighting the IME for the
- * bottom half of the display. Full screen also gives the actions a bottom bar,
- * which is where a thumb already is.
+ * Shaped like the capture sheet it replaced — a rounded card that begins below the
+ * status bar — so opening a note still reads as something rising over the board
+ * rather than a place you navigated to. It is full height rather than a real
+ * `ModalBottomSheet`, and that is the whole trade: a sheet spends a writing session
+ * negotiating with the IME for the bottom half of the display, and the swipe-down it
+ * buys is a gesture back already does. The shape is what was worth keeping.
  *
- * The note's own colour paints the WHOLE screen rather than a card inside it, so
+ * The note's own colour paints the WHOLE card rather than a panel inside it, so
  * opening a note reads as the same object growing to fill the display.
+ *
+ * No save button, deliberately. Writes are continuous, so a button offering to do
+ * what already happened would be a lie with a tap attached; [EditorFooter] in the
+ * bottom corner says the same thing as a fact instead, beside the Done that
+ * leaves.
  */
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
 fun NoteEditorScreen(
     note: Note,
+    sessionKey: Long,
     labels: List<Label>,
     saving: Boolean,
     error: String?,
     onAction: (EditorAction) -> Unit,
 ) {
     val dark = isSystemInDarkTheme()
-    val tint = noteTint(note.color)
+    val tint = noteTintFor(note)
 
-    // Keyed by note id: the editor is reused across notes, and without the key the
-    // second note opened would show the first one's text.
-    var body by remember(note.id) { mutableStateOf(note.body) }
-    var picker by remember(note.id) { mutableStateOf(Picker.NONE) }
-    var confirmingDelete by remember(note.id) { mutableStateOf(false) }
+    // Keyed by the SESSION, not by note.id: the editor is reused across notes, so it
+    // needs a key — but a draft's id changes the moment it is first saved, and
+    // re-keying on that would reset this state to whatever the store just returned,
+    // throwing away every character typed during the write.
+    //
+    // BLOCKS rather than one string, because a checklist item is drawn as a real
+    // checkbox now and a widget cannot live inside a text field. The note is still one
+    // markdown body underneath — see EditorBlock.kt — and `bodyText` is what is saved.
+    //
+    // Saveable, because a new note has nothing to fall back on if the phone rotates
+    // mid-capture. The saver carries the TEXT and re-derives the shape, since a block's
+    // id means nothing across a process death.
+    var blocks by
+        rememberSaveable(sessionKey, stateSaver = blocksSaver) {
+            mutableStateOf(splitBlocks(note.body).focusedAtEnd())
+        }
+    // Which field the caret is wanted in, or null. Held HERE rather than inside
+    // BlockBody because the toolbar's checklist button also asks for one.
+    var focus by remember(sessionKey) { mutableStateOf<Long?>(null) }
+
+    val bodyText = remember(blocks) { joinBlocks(blocks) }
+
+    var picker by remember(sessionKey) { mutableStateOf(Picker.NONE) }
+    var confirmingDelete by remember(sessionKey) { mutableStateOf(false) }
 
     // A note in the trash is a record, not a document: editing one would silently
     // resurrect work that was meant to be thrown away. It renders read-only, with
@@ -75,8 +100,8 @@ fun NoteEditorScreen(
     // would bump `updated_at`, mark the note dirty for sync, and snapshot a
     // revision identical to the one before it.
     val flush = {
-        if (!readOnly && body != note.body) {
-            onAction(EditorAction.SaveText(body))
+        if (!readOnly && bodyText != note.body) {
+            onAction(EditorAction.SaveText(bodyText))
         }
     }
     val leave = {
@@ -84,6 +109,32 @@ fun NoteEditorScreen(
         onAction(EditorAction.Close)
     }
 
+    // Opening an existing note means continuing it. Without this the note arrives
+    // unfocused, and carrying on costs a tap into the last field.
+    //
+    // Not for a trashed note: it renders read-only, and a keyboard over a record you
+    // cannot edit is noise.
+    LaunchedEffect(sessionKey) {
+        if (!readOnly) focus = blocks.lastOrNull()?.id
+    }
+
+    // Idle-debounced autosave. LaunchedEffect cancels and restarts on every
+    // keystroke, so the delay only ever elapses once typing stops.
+    //
+    // Saving this often is affordable because a body write no longer costs a
+    // revision: history snapshots once per editing session rather than once per
+    // save. Before that, writing was expensive enough that this editor hoarded
+    // text until it closed — and an app kill mid-session lost the lot.
+    //
+    // For a note that does not exist yet this is also what CREATES it, which is why
+    // every toolbar button works moments after the first keystroke rather than
+    // needing the note to be saved by hand first.
+    LaunchedEffect(bodyText, sessionKey) {
+        if (readOnly || bodyText == note.body) return@LaunchedEffect
+        delay(AUTOSAVE_IDLE_MS)
+        onAction(EditorAction.SaveText(bodyText))
+    }
+
     BackHandler(onBack = leave)
 
     // Leaving the APP is not closing the editor, so the text has to be saved
@@ -91,71 +142,101 @@ fun NoteEditorScreen(
     // is exactly the failure that makes someone stop trusting a notes app.
     FlushOnStop(flush)
 
+    // The sheet shape, kept. `windowInsetsPadding` both insets the card below the
+    // status bar AND consumes that inset, so the bar inside adds no second gap of
+    // its own — the strip above the rounded corner is what makes this read as a card
+    // over the board rather than a screen that replaced it.
+    Box(
+        modifier =
+            Modifier
+                .fillMaxSize()
+                .windowInsetsPadding(WindowInsets.statusBars),
+    ) {
+        Surface(
+            modifier = Modifier.fillMaxSize(),
+            shape = RoundedCornerShape(topStart = SHEET_CORNER, topEnd = SHEET_CORNER),
+            color = noteCardColor(note, dark),
+            // Both content colours are spelled out for the reason the toolbar had to
+            // be: Surface and Scaffold each default theirs to contentColorFor(their
+            // container), which returns Unspecified for anything that is not a
+            // colour-SCHEME ROLE. A note tint never is, so the default publishes
+            // Unspecified as LocalContentColor and everything inside that does not
+            // set its own colour draws black — which is how the last toolbar became
+            // invisible in dark mode.
+            contentColor = MaterialTheme.colorScheme.onSurface,
+        ) {
             Scaffold(
-        containerColor = tint.background(dark),
+                containerColor = noteCardColor(note, dark),
+                contentColor = MaterialTheme.colorScheme.onSurface,
                 topBar = {
-            TopAppBar(
-                title = {},
-                navigationIcon = {
-                    IconButton(onClick = leave) {
-                        Icon(
-                            Icons.AutoMirrored.Filled.ArrowBack,
-                            contentDescription = stringResource(R.string.editor_back),
-                        )
-                    }
-                },
-                colors = TopAppBarDefaults.topAppBarColors(containerColor = tint.background(dark)),
-            )
-        },
-        bottomBar = {
-            EditorBottomBar(
+                    EditorTopBar(
                         note = note,
                         readOnly = readOnly,
                         tint = tint,
+                        onClose = leave,
+                        onStartChecklist = {
+                            val (next, id) = blocks.plusTask()
+                            blocks = next
+                            focus = id
+                        },
                         onPicker = { picker = it },
                         onConfirmDelete = { confirmingDelete = true },
                         onAction = onAction,
                     )
                 },
+                // Where the action bar used to be, carrying the two things that
+                // belong within reach of a thumb: whether the note is safe, and the
+                // way out. See [EditorFooter] for why the exit is down here and not
+                // only in the top-left corner.
+                bottomBar = {
+                    EditorFooter(
+                        updatedAt = note.updatedAt,
+                        saving = saving,
+                        tint = tint,
+                        onClose = leave,
+                    )
+                },
             ) { padding ->
                 Column(
                     modifier =
                         Modifier
                             .fillMaxSize()
+                            // No imePadding here: EditorFooter carries it, so
+                            // Scaffold measures that row at its keyboard-lifted
+                            // height and the inset already reaches this Column
+                            // through `padding`. Adding it again would inset for the
+                            // keyboard twice.
                             .padding(padding)
-                    .imePadding()
                             .verticalScroll(rememberScrollState())
                             .padding(horizontal = 16.dp),
                 ) {
-            // A one-pixel line, not a spinner: a save slow enough to see is worth
-            // showing, and one that isn't must not make the screen jump.
-            if (saving) {
-                LinearProgressIndicator(modifier = Modifier.fillMaxWidth())
-            }
-
-            // A failed save has to be visible HERE. The board renders the same
-            // banner, but a write that fails while the editor is open would
-            // otherwise report itself only after the user had already left.
+                    // A failed save has to be visible HERE. The board renders the
+                    // same banner, but a write that fails while the editor is open
+                    // would otherwise report itself only after the user had already
+                    // left.
                     error?.let { message ->
-                ErrorBanner(message = message, onDismiss = { onAction(EditorAction.DismissError) })
+                        ErrorBanner(
+                            message = message,
+                            onDismiss = { onAction(EditorAction.DismissError) },
+                        )
                     }
 
-            // One field. A note is its body; its NAME is that body's first line, so
-            // there is nothing separate to type into and nothing to render bolder
-            // than the line beneath it (M13 steps 3 and 4).
-            EditorField(
-                value = body,
-                onValueChange = { body = it },
-                hint = R.string.editor_body_hint,
-                enabled = !readOnly,
-                minLines = MIN_BODY_LINES,
+                    // A note is its body; its NAME is that body's first line, so there
+                    // is nothing separate to type into and nothing rendered bolder than
+                    // the line beneath it (M13 steps 3 and 4). What 2992 changed is only
+                    // how the body is DRAWN — checklist items as boxes rather than as
+                    // the markup for boxes.
+                    BlockBody(
+                        blocks = blocks,
+                        readOnly = readOnly,
+                        focus = focus,
+                        onChange = { blocks = it },
+                        onFocus = { focus = it },
                     )
 
-            // Below the body, not instead of it, and only once the note has items —
-            // the toolbar's add-checklist action is what puts the first one there.
-            if (note.items.isNotEmpty()) {
-                ChecklistEditor(note = note, readOnly = readOnly, onAction = onAction)
-            }
+                    // No checklist section. The items ARE lines of the field above
+                    // (M304) — rendering them again down here is what would put every
+                    // list on screen twice.
 
                     if (note.labels.isNotEmpty()) {
                         EditorLabelRow(note = note, readOnly = readOnly, onAction = onAction)
@@ -171,6 +252,8 @@ fun NoteEditorScreen(
                     }
                 }
             }
+        }
+    }
 
     EditorOverlays(
         note = note,
@@ -245,32 +328,16 @@ private fun EditorOverlays(
 }
 
 /**
- * The note's body field.
+ * How long typing has to stop before the note is written.
  *
- * Undecorated, via the shared [PlainTextField]: the screen is already painted in
- * the note's colour, and a filled field would draw a second surface over the first
- * and turn a note into a form.
- *
- * One weight throughout. The first line is the note's name, but it is not a
- * different KIND of text from the line after it, and typing it should not feel like
- * filling in a header.
+ * Long enough that a normal sentence is one write, short enough that nothing
+ * meaningful is at risk if the app dies. The flush on close and [FlushOnStop] still
+ * cover the window between the last keystroke and this elapsing.
  */
-@Composable
-private fun EditorField(
-    value: String,
-    onValueChange: (String) -> Unit,
-    @StringRes hint: Int,
-    enabled: Boolean,
-    minLines: Int = 1,
-) {
-    PlainTextField(
-        value = value,
-        onValueChange = onValueChange,
-        hint = hint,
-        enabled = enabled,
-        minLines = minLines,
-        textStyle = MaterialTheme.typography.bodyLarge,
-    )
-}
+private const val AUTOSAVE_IDLE_MS = 1_000L
 
-private const val MIN_BODY_LINES = 6
+/**
+ * The card's top corner radius — Material's extra-large, which is what a bottom
+ * sheet uses. Same shape as the capture surface this replaced, on purpose.
+ */
+private val SHEET_CORNER = 28.dp

android/app/src/main/java/com/fabledsword/thoughtsync/ui/NoteTint.kt

@@ -3,6 +3,7 @@ package com.fabledsword.thoughtsync.ui
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.ReadOnlyComposable
 import androidx.compose.ui.graphics.Color
+import com.fabledsword.thoughtsync.core.Note
 
 /**
  * The note colour palette, matching `frontend/src/notes/colors.ts` VALUE FOR VALUE.
@@ -13,9 +14,12 @@ import androidx.compose.ui.graphics.Color
  * is amber on the desktop is the same amber on the phone rather than a near-miss.
  * Generated from tailwindcss 3.4's palette rather than transcribed by eye.
  *
- * Dark tints keep the web's ALPHA (`dark:bg-red-950/40`) instead of a
- * precomputed blend — Compose composites a translucent colour over what's beneath
- * exactly as CSS does, so the card sits on the background the same way in both.
+ * Dark tints keep the web's ALPHA (`dark:bg-red-950/70`) instead of a precomputed
+ * blend — Compose composites a translucent colour over what's beneath exactly as CSS
+ * does, so the card sits on the background the same way in both.
+ *
+ * This table is the palette of MEANINGFUL colours: a tag's. The fill an untagged note
+ * wears is generated rather than looked up, and lives in DerivedTint.kt.
  *
  * `yellow` maps to Tailwind's *amber*, matching colors.ts; plain yellow is too
  * acid against the neutral surfaces.
@@ -30,16 +34,86 @@ data class NoteTint(
     val lightChipForeground: Color,
     val darkChipBackground: Color,
     val darkChipForeground: Color,
+    /**
+     * False only for `default`, which is the ABSENCE of a colour rather than one of
+     * them. A tint can be drawn at the chosen weight (see [chosenBackground]);
+     * `default` cannot, because there is no such thing as an emphatic lack of colour —
+     * and re-alphaing its opaque neutral fill would make a draft card translucent.
+     */
+    val tintable: Boolean = true,
 ) {
     fun background(dark: Boolean): Color = if (dark) darkBackground else lightBackground
 
+    /**
+     * The fill for a note whose colour was CHOSEN — by a tag, or (until step 5) by
+     * the picker. A note with no tag does not come through here at all; see
+     * [noteCardColor].
+     *
+     * That split IS the design. The palette's nine keys mean something: which tag.
+     * An untagged note's fill means nothing, and tying the two together is what left
+     * the board monolithic — nine keys is far too few for a board of any size, and
+     * subdued enough not to shout they became indistinguishable from one another
+     * (measured: the nine dark fills sat within a 1.03 contrast of each other).
+     * Meaning gets a palette; texture gets a generator.
+     *
+     * THE CARD'S EDGE IS NOT A TINT and never comes from here. It used to be a 1px
+     * `{hue}-900` border measuring 1.56–2.09 against its own fill while the fill
+     * managed 1.03–1.05 against the board — the loudest thing on every card saying
+     * exactly what the fill already said, so a field of them read as a grid of
+     * outlines. The edge is now one grey for all ten keys, held as a constant in
+     * `NoteCard.kt` where the palette cannot reach it. [border] is untouched and
+     * still serves panels, banners, the update card and the pickers.
+     *
+     * Light is one Tailwind step deeper (`-100`, which is exactly
+     * [lightChipBackground] — already in this table, so no new hex is transcribed);
+     * dark is the `-950` at [STRONG_DARK_ALPHA].
+     */
+    fun chosenBackground(dark: Boolean): Color =
+        when {
+            !tintable -> background(dark)
+            dark -> darkBackground.copy(alpha = STRONG_DARK_ALPHA)
+            else -> lightChipBackground
+        }
+
     fun border(dark: Boolean): Color = if (dark) darkBorder else lightBorder
 
     fun chipBackground(dark: Boolean): Color = if (dark) darkChipBackground else lightChipBackground
 
     fun chipForeground(dark: Boolean): Color = if (dark) darkChipForeground else lightChipForeground
+
+    /**
+     * A hairline edge for a chip, in its own text colour at low alpha.
+     *
+     * Needed because a chip's fill can no longer be trusted to differ from what is
+     * behind it. A tagged note takes its FIRST tag's colour, and that card is drawn
+     * at exactly [lightChipBackground] — the same value the chip uses — so in light
+     * mode the pill was measured at a contrast ratio of 1.00 against the card it had
+     * itself coloured. Perfectly invisible: the tag name read as loose text.
+     *
+     * An edge rather than shifting the fill, because the fill can collide with any
+     * card colour and chasing that needs the chip to know what it is sitting on. A
+     * border in the chip's own foreground always reads, against any background, and
+     * needs no plumbing.
+     */
+    fun chipBorder(dark: Boolean): Color = chipForeground(dark).copy(alpha = CHIP_EDGE_ALPHA)
 }
 
+// How strongly a chip's edge is drawn, as a fraction of its own text colour.
+//
+// 0.60 measured, not guessed: against the worst case — a chip on a card of its own
+// colour — this is a 2.32:1 boundary, where 0.30 gave only 1.49:1 and was effectively
+// no edge at all. It does NOT reach the 3:1 of WCAG 1.4.11, which needs 0.80 and
+// draws a hard outline rather than a hairline. 1.4.11 governs boundaries that carry
+// REQUIRED information, and a chip's information is its text — which passes AA at
+// 8:1 or better on every card in the palette. The edge restores the pill's shape;
+// it does not carry the meaning. Raise to 0.80 if that judgment is ever overruled.
+private const val CHIP_EDGE_ALPHA = 0.60f
+
+// The chosen weight in dark, as a fraction. Mirrors `dark:bg-{hue}-950/70` in
+// colors.ts. There is no counterpart any more: an untagged note's fill is generated
+// rather than drawn from this table at a second weight. See DerivedTint.kt.
+private const val STRONG_DARK_ALPHA = 0.70f
+
 /** Keyed by the core's colour vocabulary. Order matches the web's picker. */
 val NOTE_TINTS: Map<String, NoteTint> =
     mapOf(
@@ -54,6 +128,7 @@ val NOTE_TINTS: Map<String, NoteTint> =
                 lightChipForeground = Color(0xFF525252),
                 darkChipBackground = Color(0x1AFFFFFF),
                 darkChipForeground = Color(0xFFD4D4D4),
+                tintable = false,
             ),
         "red" to
             NoteTint(
@@ -175,3 +250,75 @@ val NOTE_TINTS: Map<String, NoteTint> =
 @Composable
 @ReadOnlyComposable
 fun noteTint(key: String): NoteTint = NOTE_TINTS[key] ?: NOTE_TINTS.getValue("default")
+
+/**
+ * The tint for a NOTE, which is not the same thing as looking up its stored key: a
+ * note that has no colour of its own gets one derived from its id, so that a board
+ * of untagged notes reads as individual items rather than a wall of white.
+ *
+ * See `DerivedTint.kt` — the rule lives there, free of Compose, so it can be tested.
+ */
+@Composable
+@ReadOnlyComposable
+fun noteTintFor(note: Note): NoteTint =
+    noteTint(resolvedNoteColor(note.id, note.color, firstLabelColor(note), NOTE_TINTS.keys))
+
+/**
+ * Whether this note's colour was chosen rather than generated — see [noteCardColor].
+ *
+ * Not `@Composable`: the card needs it alongside `isSystemInDarkTheme()`, and keeping
+ * it an ordinary function means it can be read anywhere the note is.
+ */
+private fun noteIsStrong(note: Note): Boolean = noteColorIsChosen(note.color, firstLabelColor(note), NOTE_TINTS.keys)
+
+/**
+ * The single answer to "what colour is this card", from either of the two sources.
+ *
+ * A tagged note takes its tag's colour out of [NOTE_TINTS]; an untagged one gets a
+ * fill generated from its id, which is not a palette key at all. Callers ask this
+ * rather than choosing between them, so the two paths cannot drift apart between the
+ * board and the editor.
+ *
+ * A draft carries DRAFT_ID ("") and stays on the plain surface — there is no identity
+ * to derive from yet, and hashing the empty string would give every draft the same
+ * fill and then change it at save time anyway.
+ */
+@Composable
+@ReadOnlyComposable
+fun noteCardColor(
+    note: Note,
+    dark: Boolean,
+): Color =
+    when {
+        noteIsStrong(note) -> noteTintFor(note).chosenBackground(dark)
+        note.id.isEmpty() -> NOTE_TINTS.getValue("default").background(dark)
+        else -> Color(derivedFillArgb(note.id, dark))
+    }
+
+/**
+ * The colour of the note's FIRST label, already resolved, or "" when it has none.
+ *
+ * First rather than any other: it is the one the person controls by typing, where
+ * alphabetical or most-used would move a note's colour when an unrelated tag was
+ * added somewhere else. Manual labels count the same as `#tags` — someone looking at
+ * a chip cannot tell which kind they made, and two identically-tagged notes in
+ * different colours for an invisible reason is worse than the rule being loose.
+ */
+private fun firstLabelColor(note: Note): String {
+    val first = note.labels.firstOrNull() ?: return ""
+    return resolvedLabelColor(first.name, first.color, NOTE_TINTS.keys)
+}
+
+/**
+ * The tint for a LABEL, derived from its name when nobody has picked one.
+ *
+ * Every `#tag` is born colourless, so without this a board of tags is a board of
+ * identical grey chips. See `DerivedTint.kt` for why this derives rather than
+ * persisting a colour when the tag is minted.
+ */
+@Composable
+@ReadOnlyComposable
+fun labelTintFor(
+    name: String,
+    color: String,
+): NoteTint = noteTint(resolvedLabelColor(name, color, NOTE_TINTS.keys))

android/app/src/main/java/com/fabledsword/thoughtsync/ui/PlainField.kt

@@ -9,6 +9,7 @@ import androidx.compose.material3.LocalTextStyle
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.material3.TextField
+import androidx.compose.material3.TextFieldColors
 import androidx.compose.material3.TextFieldDefaults
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
@@ -20,12 +21,16 @@ import androidx.compose.ui.text.input.VisualTransformation
 /**
  * A text field with no box around it.
  *
- * Every writing surface in the app — the capture sheet, the editor's title and
- * body, each checklist row — sits on a surface that already has its own edges and
- * its own colour. Material's filled field would draw a second, differently
- * coloured box inside the first, which makes writing a note look like filling in a
- * form. Stripping the container and the indicator in four places independently is
- * how they drift apart, so it happens once, here.
+ * The search box, the label picker, the sync-pairing form: fields that sit on a
+ * surface which already has its own edges and its own colour, where Material's filled
+ * field would draw a second, differently coloured box inside the first. Stripping the
+ * container and the indicator at each site independently is how they drift apart, so
+ * it happens once, here.
+ *
+ * The note EDITOR no longer comes through this. It dropped to `BasicTextField`
+ * (see `EditorBlock.kt`) for density: Material's field puts 16dp above and below its
+ * text, which is right for a form and is the whole row height on a checklist. Nothing
+ * about "no box" was lost there — BasicTextField never had one.
  *
  * The disabled colours are stripped too: a trashed note is shown through this
  * field read-only, and Material's disabled treatment would grey out text the user
@@ -58,11 +63,21 @@ fun PlainTextField(
         keyboardOptions = keyboardOptions,
         keyboardActions = keyboardActions,
         visualTransformation = visualTransformation,
-        colors =
+        colors = plainFieldColors(),
+    )
+}
+
+/**
+ * One definition of "no box". Two copies of this is exactly the drift this file
+ * exists to prevent.
+ */
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+private fun plainFieldColors(): TextFieldColors =
     TextFieldDefaults.colors(
-                // Full-strength, not Material's 38%-alpha disabled treatment: a
-                // trashed note is rendered read-only through this field and its
-                // text is meant to be READ, not visually retired.
+        // Full-strength, not Material's 38%-alpha disabled treatment: a trashed
+        // note is rendered read-only through this field and its text is meant to
+        // be READ, not visually retired.
         disabledTextColor = MaterialTheme.colorScheme.onSurface,
         focusedContainerColor = Color.Transparent,
         unfocusedContainerColor = Color.Transparent,
@@ -70,6 +85,4 @@ fun PlainTextField(
         focusedIndicatorColor = Color.Transparent,
         unfocusedIndicatorColor = Color.Transparent,
         disabledIndicatorColor = Color.Transparent,
-            ),
     )
-}

android/app/src/main/java/com/fabledsword/thoughtsync/ui/Time.kt

@@ -1,6 +1,5 @@
 package com.fabledsword.thoughtsync.ui
 
-import java.time.Instant
 import java.time.LocalDateTime
 import java.time.OffsetDateTime
 import java.time.ZoneId
@@ -67,9 +66,14 @@ fun reminderLabel(
         }
     }
 
+/** A stored instant as epoch milliseconds, or null if it will not parse. */
+fun epochMillis(raw: String): Long? = runCatching { OffsetDateTime.parse(raw).toInstant().toEpochMilli() }.getOrNull()
+
 /** Whether a stored reminder has already passed, for showing it as overdue. */
-fun isPast(raw: String): Boolean =
-    runCatching { OffsetDateTime.parse(raw).toInstant() < Instant.now() }.getOrDefault(false)
+fun isPast(raw: String): Boolean {
+    val at = epochMillis(raw) ?: return false
+    return at < System.currentTimeMillis()
+}
 
 /**
  * Whether a timestamp is older than [minutes] ago — or absent entirely.
@@ -83,8 +87,8 @@ fun olderThan(
     raw: String?,
     minutes: Long,
 ): Boolean {
-    val at = raw?.let { runCatching { OffsetDateTime.parse(it).toInstant() }.getOrNull() }
-    return at == null || at < Instant.now().minusSeconds(minutes * SECONDS_PER_MINUTE)
+    val at = raw?.let { epochMillis(it) }
+    return at == null || at < System.currentTimeMillis() - minutes * MILLIS_PER_MINUTE
 }
 
-private const val SECONDS_PER_MINUTE = 60L
+private const val MILLIS_PER_MINUTE = 60_000L

android/app/src/main/java/com/fabledsword/thoughtsync/ui/UpdateCard.kt

@@ -1,18 +1,27 @@
 package com.fabledsword.thoughtsync.ui
 
+import androidx.compose.foundation.background
+import androidx.compose.foundation.border
+import androidx.compose.foundation.isSystemInDarkTheme
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.material3.Button
+import androidx.compose.material3.CircularProgressIndicator
 import androidx.compose.material3.LinearProgressIndicator
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.material3.TextButton
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
 import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.unit.dp
@@ -113,6 +122,59 @@ fun UpdateCard(
     }
 }
 
+/**
+ * The nag: an update is waiting, said where someone will actually see it.
+ *
+ * Until this existed the only way to learn about a new build was to open the sync
+ * screen and press Check — so the updates that got installed were the ones somebody
+ * went looking for, and the rest were simply never found.
+ *
+ * Only ever shown once the build is DOWNLOADED, so the offer is a single tap rather
+ * than the start of a wait — and so nothing is said at all until the app has been on
+ * wifi, which is where the fetch happens.
+ *
+ * Dismissible, but not permanently. "Later" clears it for this sitting; the next time
+ * the app comes forward it says so again. That is the difference between a reminder
+ * and a notice you can lose.
+ */
+@Composable
+fun UpdateBanner(
+    version: String,
+    busy: Boolean,
+    onInstall: () -> Unit,
+    onDismiss: () -> Unit,
+) {
+    val dark = isSystemInDarkTheme()
+    val tint = noteTint("blue")
+    Row(
+        modifier =
+            Modifier
+                .fillMaxWidth()
+                .padding(horizontal = 12.dp, vertical = 4.dp)
+                .clip(RoundedCornerShape(BANNER_RADIUS))
+                .background(tint.background(dark))
+                .border(1.dp, tint.border(dark), RoundedCornerShape(BANNER_RADIUS))
+                .padding(start = 12.dp),
+        verticalAlignment = Alignment.CenterVertically,
+    ) {
+        Text(
+            text = stringResource(R.string.update_banner_ready, version),
+            style = MaterialTheme.typography.bodyMedium,
+            modifier = Modifier.weight(1f),
+        )
+        if (busy) {
+            CircularProgressIndicator(modifier = Modifier.size(BANNER_SPINNER), strokeWidth = 2.dp)
+            Spacer(Modifier.size(12.dp))
+        } else {
+            TextButton(onClick = onDismiss) { Text(stringResource(R.string.update_later)) }
+            TextButton(onClick = onInstall) { Text(stringResource(R.string.update_install)) }
+        }
+    }
+}
+
+private val BANNER_RADIUS = 12.dp
+private val BANNER_SPINNER = 18.dp
+
 /**
  * The one line an unlinked device gets.
  *

android/app/src/main/java/com/fabledsword/thoughtsync/ui/UpdateViewModel.kt

@@ -24,10 +24,28 @@ data class UpdateState(
     val available: ClientUpdate? = null,
     /** A check completed and found nothing. Distinct from "not checked yet". */
     val upToDate: Boolean = false,
+    /** The available build has been fetched and is sitting in the cache. */
+    val ready: Boolean = false,
+    val downloading: Boolean = false,
     val working: Boolean = false,
     val error: String? = null,
+    /** The banner has been waved away — until the app next comes forward. */
+    val nagDismissed: Boolean = false,
 ) {
-    val busy: Boolean get() = checking || working
+    val busy: Boolean get() = checking || downloading || working
+
+    /**
+     * Worth interrupting the board for.
+     *
+     * Gated on [ready], so the banner never appears until the bytes are on disk. An
+     * update that has been FOUND is not news anyone can act on quickly — offering it
+     * off wifi would turn one tap into a download somebody did not plan.
+     *
+     * Deliberately still true while [working]: the install is the one moment the
+     * banner has something to report, and hiding it there would look like the tap
+     * did nothing.
+     */
+    val nagging: Boolean get() = ready && available != null && !nagDismissed
 }
 
 /**
@@ -53,28 +71,103 @@ class UpdateViewModel(
     var state by mutableStateOf(UpdateState(installedVersion = AppUpdate.installedVersionCode(context)))
         private set
 
-    /** Ask the linked server what it has. */
-    fun check() {
+    /** When the last check ran, so coming back to the app twice in a minute is one. */
+    private var lastCheckAt = 0L
+
+    /** Ask the linked server what it has. The Check button on the sync screen. */
+    fun check() = runCheck(fetch = false)
+
+    /**
+     * The automatic path: look, fetch, then nag.
+     *
+     * Called when the app comes forward. Until this existed an update was only ever
+     * found by someone opening the sync screen and pressing a button — so the ones
+     * that mattered were the ones nobody went looking for.
+     *
+     * Skipped when a check is already in flight, when a build is already waiting, and
+     * when one ran recently: flicking between two apps is not a request to re-check.
+     */
+    fun checkInBackground() {
+        val now = System.currentTimeMillis()
+        when {
+            state.busy -> Unit
+
+            // Already fetched and waved away — say so again. "Later" is for that
+            // sitting, not forever, and without this branch a single dismissal would
+            // silence the update permanently. Which is precisely the "lost" this whole
+            // path exists to prevent.
+            state.ready -> if (state.nagDismissed) state = state.copy(nagDismissed = false)
+
+            // Found one and never fetched it — almost always because the last look
+            // happened on mobile data. Retry the FETCH rather than the check, and
+            // ignore the interval: this is what makes an update found on the train
+            // arrive when the person gets home instead of waiting out six hours.
+            state.available != null ->
+                if (AppUpdate.onWifi(context)) viewModelScope.launch { download() }
+
+            // Flicking between two apps is not a request to re-check.
+            now - lastCheckAt < CHECK_INTERVAL_MS -> Unit
+
+            else -> {
+                lastCheckAt = now
+                runCheck(fetch = true)
+            }
+        }
+    }
+
+    private fun runCheck(fetch: Boolean) {
         viewModelScope.launch {
             state = state.copy(checking = true, error = null, upToDate = false)
             state =
                 try {
                     val found = core.clientUpdate(state.installedVersion)
-                    state.copy(checking = false, available = found, upToDate = found == null)
+                    state.copy(
+                        checking = false,
+                        available = found,
+                        upToDate = found == null,
+                        // A build that is still there is worth mentioning again. The
+                        // dismissal was for that sitting, not for this version.
+                        nagDismissed = if (found == null) state.nagDismissed else false,
+                    )
                 } catch (e: Exception) {
                     // Broad by intent, as everywhere the core is called: it reports
                     // every failure as one error type carrying a message written to
                     // be read, and a failed check must not take the screen down.
                     state.copy(checking = false, error = e.message ?: FALLBACK)
                 }
+            // Fetched before anything is said, so the banner is a one-tap install
+            // rather than the start of a wait. Off wifi this simply does not happen
+            // and the app stays quiet — the next foreground on wifi picks it up.
+            if (fetch && state.available != null && AppUpdate.onWifi(context)) {
+                download()
+            }
         }
     }
 
+    /** Fetch the waiting build into the cache, leaving it for [install]. */
+    private suspend fun download() {
+        state = state.copy(downloading = true, error = null)
+        state =
+            try {
+                core.downloadClientUpdate(AppUpdate.downloadTarget(context).absolutePath)
+                state.copy(downloading = false, ready = true)
+            } catch (e: Exception) {
+                state.copy(downloading = false, error = e.message ?: FALLBACK_DOWNLOAD)
+            }
+    }
+
+    /** Stop nagging for this sitting. The next trip to the foreground says it again. */
+    fun dismissNag() {
+        state = state.copy(nagDismissed = true)
+    }
+
     /**
-     * Download the update and hand it to the system installer.
+     * Hand the update to the system installer, downloading first if it is not already
+     * in the cache.
      *
-     * One action rather than two buttons: nobody wants a downloaded APK sitting
-     * around as an intermediate state they have to think about.
+     * Still one action from the outside. A downloaded APK is not a state anyone wants
+     * to think about, so whether the fetch already happened in the background is this
+     * class's problem rather than the person's.
      */
     fun downloadAndInstall() {
         viewModelScope.launch {
@@ -83,7 +176,7 @@ class UpdateViewModel(
             val failure =
                 try {
                     val target = AppUpdate.downloadTarget(context)
-                    core.downloadClientUpdate(target.absolutePath)
+                    if (!state.ready) core.downloadClientUpdate(target.absolutePath)
                     // Off the main thread: this streams ~55 MiB into the session.
                     withContext(Dispatchers.IO) { AppUpdate.install(context, target) }
                 } catch (e: Exception) {
@@ -126,3 +219,14 @@ class UpdateViewModel(
 }
 
 private const val FALLBACK = "The update couldn't be checked."
+private const val FALLBACK_DOWNLOAD = "The update couldn't be downloaded."
+
+/**
+ * How long a background check stays good for.
+ *
+ * Long enough that switching to another app and back is not a re-check; short enough
+ * that a build published this morning is offered today. The same reasoning as sync's
+ * STALE_MINUTES, at a slower cadence — an app update is not urgent, it is just
+ * something that must not get lost.
+ */
+private const val CHECK_INTERVAL_MS = 6L * 60 * 60 * 1000

android/app/src/main/res/values/strings.xml

@@ -10,16 +10,9 @@
 
     <!-- Compose sheet -->
     <string name="compose_open">New note</string>
-    <string name="compose_body_hint">Take a note…</string>
-    <string name="compose_discard">Discard</string>
-    <string name="compose_save">Save</string>
 
     <!-- Board -->
     <string name="board_empty_note">Empty note</string>
-    <plurals name="board_more_items">
-        <item quantity="one">+%d more item</item>
-        <item quantity="other">+%d more items</item>
-    </plurals>
 
     <!-- Empty states. Each destination says something true of ITSELF; a single
          "nothing here" reads as encouragement on the board and as a fault in Trash. -->
@@ -38,12 +31,17 @@
     <string name="board_open_note">Open note</string>
     <string name="editor_back">Back to notes</string>
     <string name="editor_add_checklist">Add a checklist</string>
-    <string name="editor_body_hint">Note</string>
+    <string name="editor_body_hint">Take a note…</string>
     <string name="editor_add_item">Add item</string>
     <string name="editor_remove_item">Remove item</string>
     <string name="editor_remove_label">Remove label</string>
     <string name="editor_reminder">Set a reminder</string>
     <string name="editor_more">More actions</string>
+    <string name="editor_saving">Saving…</string>
+    <string name="editor_unsaved">Not saved yet</string>
+    <string name="editor_edited">Edited %1$s</string>
+    <string name="editor_just_now">just now</string>
+    <string name="editor_done">Done</string>
     <string name="editor_pin">Pin</string>
     <string name="editor_unpin">Unpin</string>
     <string name="editor_labels">Labels…</string>
@@ -122,6 +120,8 @@
     <string name="update_current">You\'re on the newest build this server has.</string>
     <string name="update_check">Check for an update</string>
     <string name="update_install">Update</string>
+    <string name="update_banner_ready">Build %1$s is downloaded and ready.</string>
+    <string name="update_later">Later</string>
     <string name="update_failed_title">The update didn\'t install</string>
     <string name="update_permission_title">Android needs your permission</string>
     <string name="update_permission_body">ThoughtSync has to be allowed to install apps before it can update itself. This is a one-time setting.</string>

android/app/src/test/java/com/fabledsword/thoughtsync/ui/DerivedTintTest.kt

@@ -0,0 +1,318 @@
+package com.fabledsword.thoughtsync.ui
+
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNotEquals
+import org.junit.Test
+
+/**
+ * Pins the derived-tint rule against `frontend/src/notes/colors.ts`.
+ *
+ * These are not tests of Kotlin — they are the ONE mechanical guard the mirrored pair
+ * has. The web side is TypeScript with no test runner (its CI lane is `vue-tsc
+ * --noEmit` and nothing else), so if these values drift, nothing on that surface will
+ * say so and a note will simply be a different colour on the phone than in the
+ * browser. The same four ids and hashes are written into colors.ts as a comment;
+ * changing either side means changing both and re-checking here.
+ */
+class DerivedTintTest {
+    @Test
+    fun `hashes match the fixture shared with the web`() {
+        // Kotlin's Int is signed, so the two hashes above 0x7FFFFFFF are written as
+        // their negative literal. The unsigned value in the comment is what colors.ts
+        // records and what an implementation of FNV-1a will actually produce.
+        assertEquals(-0x41B8712F, tintHash("00000000-0000-0000-0000-000000000000")) // 0xbe478ed1
+        assertEquals(0x3D75CC01, tintHash("11111111-1111-1111-1111-111111111111"))
+        assertEquals(-0x0EF71AD0, tintHash("6ba7b810-9dad-11d1-80b4-00c04fd430c8")) // 0xf108e530
+        assertEquals(0x5B651540, tintHash("f47ac10b-58cc-4372-a567-0e02b2c3d479"))
+    }
+
+    @Test
+    fun `tints match the fixture shared with the web`() {
+        assertEquals("purple", derivedTint("00000000-0000-0000-0000-000000000000"))
+        assertEquals("blue", derivedTint("11111111-1111-1111-1111-111111111111"))
+        assertEquals("orange", derivedTint("6ba7b810-9dad-11d1-80b4-00c04fd430c8"))
+        assertEquals("orange", derivedTint("f47ac10b-58cc-4372-a567-0e02b2c3d479"))
+    }
+
+    /** Half of all 32-bit hashes are negative as Kotlin Ints; a signed remainder would
+     *  index out of the list for those. The bug this catches is a crash, not a wrong
+     *  colour, so it is worth more than one id's worth of coverage. */
+    @Test
+    fun `every tint is a real palette key, over many ids`() {
+        for (n in 0 until 2000) {
+            val tint = derivedTint("note-$n")
+            assertEquals(true, tint in DERIVED_TINT_KEYS)
+        }
+    }
+
+    @Test
+    fun `the derived palette excludes default`() {
+        assertEquals(false, "default" in DERIVED_TINT_KEYS)
+        assertEquals(9, DERIVED_TINT_KEYS.size)
+    }
+
+    /** The order IS the mapping — reordering silently recolours every untagged note
+     *  on one surface only. Written out longhand so a reorder fails here loudly. */
+    @Test
+    fun `key order matches colors ts`() {
+        assertEquals(
+            listOf("red", "orange", "yellow", "green", "teal", "blue", "purple", "pink", "gray"),
+            DERIVED_TINT_KEYS,
+        )
+    }
+
+    @Test
+    fun `an explicitly picked colour still wins`() {
+        val known = DERIVED_TINT_KEYS.toSet() + "default"
+        assertEquals("teal", resolvedNoteColor("any-id", "teal", "", known))
+    }
+
+    @Test
+    fun `an unknown colour key falls back to the derived tint`() {
+        val known = DERIVED_TINT_KEYS.toSet() + "default"
+        val id = "00000000-0000-0000-0000-000000000000"
+        assertEquals("purple", resolvedNoteColor(id, "chartreuse", "", known))
+    }
+
+    /** `default` is not a choice, it is the absence of one — so a note stored as
+     *  `default` gets a derived tint rather than staying white. That is the whole
+     *  point of the change. */
+    @Test
+    fun `a default colour is treated as no colour`() {
+        val known = DERIVED_TINT_KEYS.toSet() + "default"
+        val id = "11111111-1111-1111-1111-111111111111"
+        assertEquals("blue", resolvedNoteColor(id, "default", "", known))
+        assertNotEquals("default", resolvedNoteColor(id, "default", "", known))
+    }
+
+    /** A draft has no id yet. It must not be hashed — see the comment in DerivedTint. */
+    @Test
+    fun `a draft stays default until it has an id`() {
+        val known = DERIVED_TINT_KEYS.toSet() + "default"
+        assertEquals("default", resolvedNoteColor("", "", "", known))
+        assertEquals("default", resolvedNoteColor("", "default", "", known))
+    }
+
+    /** The point of the whole milestone: notes sharing a tag share a colour, however
+     *  different their ids. Four `#todo` notes in four colours is what started this. */
+    @Test
+    fun `notes sharing a tag share a colour whatever their ids`() {
+        val known = DERIVED_TINT_KEYS.toSet() + "default"
+        val todo = resolvedLabelColor("todo", "default", known)
+        val a = resolvedNoteColor("11111111-1111-1111-1111-111111111111", "default", todo, known)
+        val b = resolvedNoteColor("6ba7b810-9dad-11d1-80b4-00c04fd430c8", "default", todo, known)
+        assertEquals(todo, a)
+        assertEquals(a, b)
+        // ...and it is NOT what either id would have derived on its own.
+        assertNotEquals(derivedTint("11111111-1111-1111-1111-111111111111"), a)
+    }
+
+    /** Until step 5 removes the picker, a hand-picked colour outranks the tag. */
+    @Test
+    fun `an explicit note colour still beats its tag`() {
+        val known = DERIVED_TINT_KEYS.toSet() + "default"
+        val todo = resolvedLabelColor("todo", "default", known)
+        assertNotEquals("teal", todo)
+        assertEquals("teal", resolvedNoteColor("any-id", "teal", todo, known))
+    }
+
+    /** Strength is not a second decision — it IS whether the colour was chosen. */
+    @Test
+    fun `only a chosen colour is drawn strongly`() {
+        val known = DERIVED_TINT_KEYS.toSet() + "default"
+        val todo = resolvedLabelColor("todo", "default", known)
+        assertEquals(true, noteColorIsChosen("default", todo, known))
+        assertEquals(true, noteColorIsChosen("teal", "", known))
+        assertEquals(false, noteColorIsChosen("default", "", known))
+        assertEquals(false, noteColorIsChosen("", "", known))
+        // An unrecognised key is not a choice — it is data we could not read.
+        assertEquals(false, noteColorIsChosen("chartreuse", "", known))
+    }
+
+    /** A tag with no colour of its own derives one from its NAME, which is what makes
+     *  every `#todo` note the same colour rather than nine different ones. */
+    @Test
+    fun `a label with no colour derives one from its name`() {
+        val known = DERIVED_TINT_KEYS.toSet() + "default"
+        val todo = resolvedLabelColor("todo", "default", known)
+        assertEquals(derivedTint("todo"), todo)
+        assertNotEquals("default", todo)
+    }
+
+    /** Tags dedupe case-insensitively, so `#Todo` and `#todo` are one tag and must not
+     *  be two colours. This is the whole reason the name is lowercased first. */
+    @Test
+    fun `label colour ignores case`() {
+        val known = DERIVED_TINT_KEYS.toSet() + "default"
+        assertEquals(
+            resolvedLabelColor("todo", "default", known),
+            resolvedLabelColor("ToDo", "default", known),
+        )
+    }
+
+    /** `teal` deliberately, NOT the colour "todo" derives to (pink) — asserting the
+     *  derived value here would pass even with the explicit branch deleted. */
+    @Test
+    fun `an explicitly picked label colour still wins`() {
+        val known = DERIVED_TINT_KEYS.toSet() + "default"
+        assertNotEquals("teal", derivedTint("todo"))
+        assertEquals("teal", resolvedLabelColor("todo", "teal", known))
+    }
+
+    /**
+     * The spread is real, and collisions are real too.
+     *
+     * Nine keys means two tags sharing a colour is not a bug and cannot be designed
+     * out — in this very sample `home`/`reading` are both gray and `work`/`ideas` are
+     * both green. Colour is a hint that two notes are related, never a claim that they
+     * carry the same tag; the chip's TEXT is what says which tag it is.
+     */
+    @Test
+    fun `different tag names spread across the palette`() {
+        val known = DERIVED_TINT_KEYS.toSet() + "default"
+        val names = listOf("todo", "grocery", "work", "home", "ideas", "reading", "urgent")
+        val colours = names.map { resolvedLabelColor(it, "default", known) }
+        assertEquals(true, colours.toSet().size >= 5)
+    }
+
+    /** The reason the feature exists: two adjacent notes should not look identical. */
+    @Test
+    fun `the tint spreads across the palette`() {
+        val seen = (0 until 500).map { derivedTint("spread-$it") }.toSet()
+        assertEquals(DERIVED_TINT_KEYS.size, seen.size)
+    }
+
+    // ---------------------------------------------------------------------
+    // derivedFillArgb — the generated fill an UNTAGGED note wears.
+    //
+    // A different job from the palette above, and pinned separately. The palette's
+    // nine keys mean "which tag"; this means nothing at all and exists so a board is
+    // not a monolithic wall. It was nine keys once, and measured, those nine dark
+    // fills sat within a 1.03 contrast of one another — nine tints that looked like
+    // three. These are the tests that stop that happening again.
+
+    /** The web has no test runner and cannot even be EXECUTED on the dev machine
+     *  (no node), so this fixture is the only place the two implementations are ever
+     *  actually compared. The same four ids and hexes are a comment in colors.ts. */
+    @Test
+    fun `generated fills match the fixture shared with the web`() {
+        assertEquals("#1e3130", hex(derivedFillArgb("00000000-0000-0000-0000-000000000000", dark = true)))
+        assertEquals("#1a2818", hex(derivedFillArgb("11111111-1111-1111-1111-111111111111", dark = true)))
+        assertEquals("#162419", hex(derivedFillArgb("6ba7b810-9dad-11d1-80b4-00c04fd430c8", dark = true)))
+        assertEquals("#311e20", hex(derivedFillArgb("f47ac10b-58cc-4372-a567-0e02b2c3d479", dark = true)))
+
+        assertEquals("#f3fcfb", hex(derivedFillArgb("00000000-0000-0000-0000-000000000000", dark = false)))
+        assertEquals("#fbfefb", hex(derivedFillArgb("11111111-1111-1111-1111-111111111111", dark = false)))
+        assertEquals("#ffffff", hex(derivedFillArgb("6ba7b810-9dad-11d1-80b4-00c04fd430c8", dark = false)))
+        assertEquals("#fcf3f4", hex(derivedFillArgb("f47ac10b-58cc-4372-a567-0e02b2c3d479", dark = false)))
+    }
+
+    /** The whole reason this replaced the nine-key ramp. Two orders of magnitude more
+     *  fills than the palette could offer, so a board of any size stops repeating. */
+    @Test
+    fun `the generated fill spreads far wider than the palette ever could`() {
+        val dark = (0 until 500).map { derivedFillArgb("note-$it", dark = true) }.toSet()
+        val light = (0 until 500).map { derivedFillArgb("note-$it", dark = false) }.toSet()
+        assertEquals(true, dark.size > 200)
+        assertEquals(true, light.size > 100)
+        // ...and far more than the nine it replaced, which is the actual claim.
+        assertEquals(true, dark.size > DERIVED_TINT_KEYS.size * 20)
+    }
+
+    /**
+     * Lightness is the axis that carries the variety, so it is the one worth pinning.
+     *
+     * The bug this catches is the one that shipped: a ramp that varies hue while
+     * holding lightness fixed reads as one card repeated, because the eye separates
+     * by lightness first. If someone collapses these levels again, the fills will
+     * still all be "different colours" and the board will still be a wall.
+     */
+    @Test
+    fun `generated fills vary in lightness, not only in hue`() {
+        val levels = (0 until 500).map { luminance(derivedFillArgb("note-$it", dark = true)) }.toSet()
+        assertEquals(true, levels.size >= 6)
+        assertEquals(true, levels.max() / levels.min() > 2.0)
+    }
+
+    /**
+     * Nothing may be darker than the plain card surface (`neutral-900`, #171717) in
+     * dark, or the note reads as a hole in the board rather than a card on it.
+     *
+     * THIS TEST HAS ALREADY EARNED ITS KEEP. The first floor was 0.090 — `neutral-900`'s
+     * own HSL lightness — on the reasoning that starting at the card surface and
+     * climbing could not possibly go below it. That reasoning confuses HSL lightness
+     * with luminance. At one fixed lightness the eye sees very different brightnesses
+     * by hue, because green carries 71% of the luminance formula and blue 7%: at 0.090
+     * a yellow measures 0.0118 and a blue 0.0061, so every blue-ish untagged note was
+     * 1.41x darker than the card it was supposed to match. Solved for, the floor is
+     * 0.113.
+     *
+     * Which is why this asserts on LUMINANCE and not on the input lightness — testing
+     * the number that was put in would have agreed with the bug.
+     */
+    @Test
+    fun `no generated fill sinks below the card surface`() {
+        val surface = luminance(0xFF171717.toInt())
+        for (n in 0 until 500) {
+            assertEquals(true, luminance(derivedFillArgb("note-$n", dark = true)) >= surface)
+        }
+        // The worst case is a HUE — blue, around 240 — and 500 ids are not enough to
+        // be sure of having visited it at the darkest level. There are 360 x 6 = 2160
+        // reachable combinations; by the coupon-collector bound ~16,600 draws covers
+        // them, so 40,000 makes a miss vanishingly unlikely. Cheap on the JVM, and the
+        // alternative is a test that would have PASSED against the original bug.
+        for (n in 0 until 40_000) {
+            assertEquals(true, luminance(derivedFillArgb("hue-sweep-$n", dark = true)) >= surface)
+        }
+    }
+
+    /** Body text is drawn on these. AA wants 4.5:1 and the meta row 3:1; the margin
+     *  here is enormous, and the test is what keeps it that way if the levels move. */
+    @Test
+    fun `every generated fill keeps body text well clear of AA`() {
+        for (n in 0 until 500) {
+            assertEquals(true, contrast(0xFFD4D4D4.toInt(), derivedFillArgb("note-$n", dark = true)) >= 4.5)
+            assertEquals(true, contrast(0xFF404040.toInt(), derivedFillArgb("note-$n", dark = false)) >= 4.5)
+        }
+    }
+
+    /** Same id, same fill, forever — a note that changed colour on reload would read
+     *  as corruption. The point of hashing rather than rolling a die. */
+    @Test
+    fun `the generated fill is stable for an id`() {
+        val id = "f47ac10b-58cc-4372-a567-0e02b2c3d479"
+        assertEquals(derivedFillArgb(id, dark = true), derivedFillArgb(id, dark = true))
+        assertNotEquals(derivedFillArgb(id, dark = true), derivedFillArgb(id, dark = false))
+    }
+
+    /** Every fill is fully opaque. A translucent one would composite over whatever is
+     *  behind it, and the editor sheet is not the board — the same note would be two
+     *  colours depending on where you were looking at it. */
+    @Test
+    fun `generated fills are opaque`() {
+        for (n in 0 until 100) {
+            assertEquals(0xFF, (derivedFillArgb("note-$n", dark = true) ushr 24) and 0xFF)
+        }
+    }
+
+    private fun hex(argb: Int): String = "#%06x".format(argb and 0xFFFFFF)
+
+    private fun channel(argb: Int, shift: Int): Double {
+        val c = ((argb ushr shift) and 0xFF) / 255.0
+        return if (c <= 0.03928) c / 12.92 else Math.pow((c + 0.055) / 1.055, 2.4)
+    }
+
+    /** WCAG relative luminance, so the assertions above are about what an eye sees
+     *  rather than about the bytes. */
+    private fun luminance(argb: Int): Double =
+        0.2126 * channel(argb, 16) + 0.7152 * channel(argb, 8) + 0.0722 * channel(argb, 0)
+
+    private fun contrast(
+        a: Int,
+        b: Int,
+    ): Double {
+        val la = luminance(a)
+        val lb = luminance(b)
+        return (maxOf(la, lb) + 0.05) / (minOf(la, lb) + 0.05)
+    }
+}

android/ffi/src/lib.rs

@@ -43,8 +43,8 @@ use thoughtsync_core::sync::blobs::BlobStore;
 use thoughtsync_core::sync::{client, compat, engine, push, state};
 
 use models::{
-    patch_from, ClientUpdate, Identity, Label, Note, NoteDraft, NoteEdit, NoteQuery, ProbeResult,
-    RevokeOutcome, SyncOutcome, SyncStatus,
+    patch_from, BodyItem, ClientUpdate, Identity, Label, Note, NoteDraft, NoteEdit, NoteQuery,
+    ProbeResult, RevokeOutcome, SyncOutcome, SyncStatus,
 };
 
 uniffi::setup_scaffolding!();
@@ -499,6 +499,37 @@ impl ThoughtSync {
     }
 }
 
+// ── checklist text, as pure functions ───────────────────────────────────────
+//
+// The pair the block editor is built on: one to read a body apart, one to put a line
+// back together. Between them, Kotlin can render a checklist as real checkboxes and
+// write the markdown back without owning the grammar — which is the point. Three
+// implementations of it is the price already being paid (Rust, Python, TypeScript);
+// a fourth in Compose would be one more place for a checklist to change shape when
+// it syncs.
+//
+// Free functions rather than methods, because they touch no database. The editor's
+// body is LOCAL state — autosaved on an idle debounce, not written per keystroke —
+// so editing a checklist there has to rewrite the text the editor is holding, not a
+// row the store would hand back a moment later and overwrite the typing with.
+
+/// One checklist item as the body line that stores it. For an editor that shows a
+/// checkbox instead of the markup and has to write the markup back.
+#[uniffi::export]
+pub fn checklist_render(text: String, checked: bool) -> String {
+    local::derive::render_item(&text, checked)
+}
+
+/// Every checklist item in a body, with the line each one sits on — so a renderer
+/// walking the body line by line knows which lines are boxes and what is in them.
+#[uniffi::export]
+pub fn checklist_items(body: String) -> Vec<BodyItem> {
+    local::derive::extract_items(&body)
+        .into_iter()
+        .map(BodyItem::from)
+        .collect()
+}
+
 /// Helpers, deliberately NOT exported — uniffi only binds what an `#[uniffi::export]`
 /// block names, so these stay Rust-side.
 impl ThoughtSync {
@@ -682,8 +713,9 @@ mod tests {
         assert!(ticked.items[1].checked);
         assert_eq!(
             ticked.items[1].text, "charger",
-            "ticking a box must not disturb its text — the two setters write \
-             different columns and neither may clear the other"
+            "ticking a box must not disturb its text — both setters rewrite the \
+             same line of the body now, so one clobbering the other is a live risk \
+             rather than a theoretical one"
         );
 
         let renamed = app

android/ffi/src/models.rs

@@ -49,6 +49,33 @@ pub struct Note {
     pub updated_at: Option<String>,
 }
 
+/// A checklist item as it sits in a note's body.
+///
+/// Mirrors `derive::DerivedItem`. Carries the LINE because every renderer that walks
+/// a body line by line needs the text, the state and the position together — the card
+/// to draw a box in the right place, the block editor to know where one block ends.
+#[derive(Debug, Clone, uniffi::Record)]
+pub struct BodyItem {
+    pub line: u32,
+    pub text: String,
+    pub checked: bool,
+}
+
+impl From<thoughtsync_core::local::derive::DerivedItem> for BodyItem {
+    fn from(i: thoughtsync_core::local::derive::DerivedItem) -> Self {
+        let thoughtsync_core::local::derive::DerivedItem {
+            text,
+            checked,
+            line,
+        } = i;
+        BodyItem {
+            line,
+            text,
+            checked,
+        }
+    }
+}
+
 /// An Android build the linked server is offering, already judged to be newer.
 ///
 /// A mirror rather than a re-export of `client::ClientRelease`, for the same

core/src/local/derive.rs

@@ -1,9 +1,18 @@
-//! Deriving `#tags` from a note's body — the local mirror of what the server computes
-//! on save. Pure string scanning (no regex dependency), kept in lockstep with the
-//! frontend's inline rules (see frontend notes/markdown.ts):
+//! Deriving structure from a note's body — the local mirror of what the server
+//! computes on save. Pure string scanning (no regex dependency), kept in lockstep
+//! with the frontend's inline rules (see frontend notes/markdown.ts):
 //!
 //! - `#tag`: `#` at a word boundary followed by tag characters (letter first).
 //!   On save these become labels attached with `via_tag = true`.
+//! - `- [ ] item`: a checklist item. The body IS the checklist (M304) — there is no
+//!   table of items beside it, so a list can sit between two paragraphs instead of
+//!   only after them.
+//!
+//! The two are the same idea at different strengths. Tags MATERIALISE into label
+//! rows, because the board queries by label. Items materialise into nothing,
+//! because nothing queries them: their only readers are the card, the editor and
+//! `display_title`. So `extract_items` is the whole storage layer for a checklist,
+//! and the rewriters below are how one is edited.
 //!
 //! Dedupes case-insensitively, preserving first-seen order.
 //!
@@ -45,6 +54,239 @@ fn push_unique(out: &mut Vec<String>, candidate: &str) {
     }
 }
 
+// ── checklist items ─────────────────────────────────────────────────────────
+//
+// The grammar, in one place, because three languages implement it (here,
+// `notes/checklist.py`, `notes/markdown.ts`) and a difference between any two of
+// them is a checklist that changes shape when it syncs:
+//
+//   optional indent, `-` or `*`, one-or-more spaces, `[ ]`/`[x]`/`[X]`,
+//   then either end-of-line or one-or-more spaces and the text.
+//
+// `*` is accepted because markdown.ts already accepts it for a plain bullet, and a
+// grammar that takes `* item` but not `* [ ] item` would be a rule with no reason
+// anyone could guess. `- [ ]` with nothing after it IS an item with empty text:
+// that is exactly what pressing Enter on a list leaves behind, and refusing to
+// parse it would make a half-typed list stop being a list.
+
+/// A checklist item, as found in the body. Its position in the returned vector is
+/// its identity — the same thing `position` meant when these were rows, and all the
+/// wire ever carried (`push.rs` sent text and checked, never an id).
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct DerivedItem {
+    pub text: String,
+    pub checked: bool,
+    /// Which body line it sits on.
+    ///
+    /// Carried here rather than offered as a second function, because every renderer
+    /// that walks a body line by line — the Android card, the block editor — needs the
+    /// text, the state AND the position together, and asking for them separately is
+    /// how two calls come to disagree about a body that changed between them.
+    pub line: u32,
+}
+
+/// One parsed task line, holding enough to put it back exactly as it was found.
+struct TaskLine<'a> {
+    indent: &'a str,
+    /// Preserved rather than normalised to `-`: rewriting someone's `*` bullets
+    /// because they ticked a box would be an edit they did not ask for.
+    bullet: char,
+    checked: bool,
+    text: &'a str,
+}
+
+fn parse_task_line(line: &str) -> Option<TaskLine<'_>> {
+    let indent_len = line.len() - line.trim_start().len();
+    let (indent, rest) = line.split_at(indent_len);
+
+    let bullet = rest.chars().next()?;
+    if bullet != '-' && bullet != '*' {
+        return None;
+    }
+    // At least one space after the bullet. `-[ ] x` is not a list item in any
+    // markdown either, so it stays prose here too.
+    let rest = &rest[bullet.len_utf8()..];
+    let gap = rest.len() - rest.trim_start_matches(' ').len();
+    if gap == 0 {
+        return None;
+    }
+    let rest = &rest[gap..];
+
+    let mut chars = rest.chars();
+    if chars.next()? != '[' {
+        return None;
+    }
+    let mark = chars.next()?;
+    if chars.next()? != ']' {
+        return None;
+    }
+    // Decided BEFORE the slice below, which is what guarantees `mark` is one byte
+    // and `[?]` is exactly three.
+    let checked = match mark {
+        ' ' => false,
+        'x' | 'X' => true,
+        _ => return None,
+    };
+    let rest = &rest[3..];
+
+    let text = if rest.is_empty() {
+        // "- [ ]" — an empty item, which is what an unfinished list line is.
+        rest
+    } else {
+        let gap = rest.len() - rest.trim_start_matches(' ').len();
+        // "- [ ]x" is prose: without the space this is not a marker, it is a
+        // sentence that happens to start with brackets.
+        if gap == 0 {
+            return None;
+        }
+        &rest[gap..]
+    };
+
+    Some(TaskLine {
+        indent,
+        bullet,
+        checked,
+        text,
+    })
+}
+
+/// One item as the line that stores it, in canonical form.
+///
+/// Public because a block editor has to write a line back after someone edits it in a
+/// widget that never showed them the marker. Rendering is trivial where PARSING is
+/// not, but it still belongs here: this is the file that decides what canonical looks
+/// like, and a caller inventing its own `- [x] ` would be a fourth opinion on it.
+pub fn render_item(text: &str, checked: bool) -> String {
+    render_task_line("", '-', checked, text)
+}
+
+fn render_task_line(indent: &str, bullet: char, checked: bool, text: &str) -> String {
+    // Always lowercase `x`, whatever was parsed: one canonical output is what makes
+    // a round trip stable, so `- [X]` normalises the first time it is touched and
+    // never again.
+    let mark = if checked { 'x' } else { ' ' };
+    if text.is_empty() {
+        format!("{indent}{bullet} [{mark}]")
+    } else {
+        format!("{indent}{bullet} [{mark}] {text}")
+    }
+}
+
+/// The text of a line with its task marker removed, or the line as it was.
+///
+/// For naming a note: a list-only note is named by its first item, and calling one
+/// "- [ ] milk" would be showing someone the storage instead of the note.
+pub fn strip_marker(line: &str) -> &str {
+    match parse_task_line(line) {
+        Some(t) => t.text,
+        None => line,
+    }
+}
+
+/// Every checklist item in `body`, in the order they appear.
+pub fn extract_items(body: &str) -> Vec<DerivedItem> {
+    let mut out = Vec::new();
+    for (n, line) in body.split('\n').enumerate() {
+        if let Some(t) = parse_task_line(line) {
+            out.push(DerivedItem {
+                text: t.text.to_string(),
+                checked: t.checked,
+                line: n as u32,
+            });
+        }
+    }
+    out
+}
+
+/// Rewrite the `index`-th task line, or drop it when `f` returns None.
+///
+/// A body with fewer task lines than that is returned UNCHANGED rather than
+/// panicking: the index comes from a UI that may be a moment behind the store, and
+/// a stale tap should do nothing rather than take the app down.
+fn map_task_line<F>(body: &str, index: usize, f: F) -> String
+where
+    F: FnOnce(&TaskLine<'_>) -> Option<String>,
+{
+    let lines: Vec<&str> = body.split('\n').collect();
+    let mut target: Option<usize> = None;
+    let mut seen = 0usize;
+    for (n, line) in lines.iter().enumerate() {
+        if parse_task_line(line).is_some() {
+            if seen == index {
+                target = Some(n);
+                break;
+            }
+            seen += 1;
+        }
+    }
+    let target = match target {
+        Some(n) => n,
+        None => return body.to_string(),
+    };
+    let replacement = match parse_task_line(lines[target]) {
+        Some(parsed) => f(&parsed),
+        None => return body.to_string(),
+    };
+
+    let mut out: Vec<String> = Vec::with_capacity(lines.len());
+    for (n, line) in lines.iter().enumerate() {
+        if n != target {
+            out.push((*line).to_string());
+        } else if let Some(new_line) = &replacement {
+            out.push(new_line.clone());
+        }
+        // None at the target line drops it, which is `remove_item`.
+    }
+    out.join("\n")
+}
+
+/// Tick or untick the `index`-th item.
+pub fn set_item_checked(body: &str, index: usize, checked: bool) -> String {
+    map_task_line(body, index, |t| {
+        Some(render_task_line(t.indent, t.bullet, checked, t.text))
+    })
+}
+
+/// Replace the text of the `index`-th item, keeping its state and its bullet.
+pub fn set_item_text(body: &str, index: usize, text: &str) -> String {
+    map_task_line(body, index, |t| {
+        Some(render_task_line(t.indent, t.bullet, t.checked, text.trim()))
+    })
+}
+
+/// Delete the `index`-th item, line and all.
+pub fn remove_item(body: &str, index: usize) -> String {
+    map_task_line(body, index, |_| None)
+}
+
+/// Add an item at the end of the body.
+///
+/// Spaced exactly as `import_export.py:_note_markdown` writes a list — a blank line
+/// between prose and the list, and nothing between consecutive items. That is not
+/// cosmetic: the server migration folds existing rows into bodies using the same
+/// layout, so an export taken before the migration and one taken after have to
+/// agree byte for byte.
+///
+/// `checked` is a parameter rather than always false because the two migrations that
+/// fold existing rows into bodies have to carry the state those rows were in. A new
+/// item from the UI passes false.
+pub fn append_item(body: &str, text: &str, checked: bool) -> String {
+    let line = render_task_line("", '-', checked, text.trim());
+    let trimmed = body.trim_end_matches('\n');
+    if trimmed.trim().is_empty() {
+        return line;
+    }
+    let follows_a_list = trimmed
+        .split('\n')
+        .next_back()
+        .is_some_and(|l| parse_task_line(l).is_some());
+    if follows_a_list {
+        format!("{trimmed}\n{line}")
+    } else {
+        format!("{trimmed}\n\n{line}")
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -72,4 +314,165 @@ mod tests {
     fn empty_body() {
         assert!(extract_tags("").is_empty());
     }
+
+    // ── checklist items ─────────────────────────────────────────────────────
+
+    fn item(text: &str, checked: bool, line: u32) -> DerivedItem {
+        DerivedItem {
+            text: text.to_string(),
+            checked,
+            line,
+        }
+    }
+
+    #[test]
+    fn items_basic() {
+        let body = "shopping\n\n- [ ] milk\n- [x] eggs";
+        assert_eq!(
+            extract_items(body),
+            vec![item("milk", false, 2), item("eggs", true, 3)]
+        );
+    }
+
+    #[test]
+    fn items_may_sit_between_paragraphs() {
+        // The whole reason the body owns the list: a table of rows could only ever
+        // render after the prose.
+        let body = "before\n- [ ] middle\nafter";
+        assert_eq!(extract_items(body), vec![item("middle", false, 1)]);
+    }
+
+    #[test]
+    fn items_reject_near_misses() {
+        // Each of these is prose, and each has been someone's bug report somewhere.
+        for body in [
+            "-[ ] no space after the dash",
+            "- [] empty brackets",
+            "- [ ]no space after the brackets",
+            "- [y] not a mark",
+            "a [ ] mid sentence",
+            "[ ] no bullet at all",
+        ] {
+            assert!(extract_items(body).is_empty(), "should be prose: {body}");
+        }
+    }
+
+    #[test]
+    fn items_accept_star_bullets_and_indentation() {
+        // `*` because markdown.ts already takes it for a plain bullet.
+        let body = "* [ ] star\n    - [x] indented";
+        assert_eq!(
+            extract_items(body),
+            vec![item("star", false, 0), item("indented", true, 1)]
+        );
+    }
+
+    #[test]
+    fn an_empty_item_is_still_an_item() {
+        // What pressing Enter on a list leaves behind.
+        assert_eq!(extract_items("- [ ]"), vec![item("", false, 0)]);
+        assert_eq!(extract_items("- [ ] "), vec![item("", false, 0)]);
+    }
+
+    #[test]
+    fn uppercase_x_parses_and_normalises_on_rewrite() {
+        assert_eq!(extract_items("- [X] done"), vec![item("done", true, 0)]);
+        // Touching it once canonicalises it, and never again.
+        assert_eq!(set_item_checked("- [X] done", 0, true), "- [x] done");
+    }
+
+    #[test]
+    fn checking_preserves_indent_bullet_and_text() {
+        assert_eq!(set_item_checked("  * [ ] milk", 0, true), "  * [x] milk");
+        assert_eq!(set_item_checked("- [x] milk", 0, false), "- [ ] milk");
+    }
+
+    #[test]
+    fn checking_addresses_items_not_lines() {
+        let body = "note\n- [ ] a\nprose\n- [ ] b";
+        assert_eq!(
+            set_item_checked(body, 1, true),
+            "note\n- [ ] a\nprose\n- [x] b"
+        );
+    }
+
+    #[test]
+    fn set_text_keeps_state() {
+        assert_eq!(set_item_text("- [x] old", 0, "new"), "- [x] new");
+    }
+
+    #[test]
+    fn remove_takes_the_whole_line() {
+        let body = "keep\n- [ ] drop\n- [ ] stay";
+        assert_eq!(remove_item(body, 0), "keep\n- [ ] stay");
+    }
+
+    #[test]
+    fn append_spaces_like_the_exporter() {
+        // Prose then a blank line then the list — byte-for-byte what
+        // import_export.py:_note_markdown writes, which is what the server
+        // migration will fold existing rows into.
+        assert_eq!(append_item("a note", "milk", false), "a note\n\n- [ ] milk");
+        // Nothing between consecutive items.
+        let one = "a note\n\n- [ ] milk";
+        assert_eq!(
+            append_item(one, "eggs", false),
+            format!("{one}\n- [ ] eggs")
+        );
+        // A list-only note starts at the first line.
+        assert_eq!(append_item("", "milk", false), "- [ ] milk");
+        assert_eq!(append_item("\n\n", "milk", false), "- [ ] milk");
+        // Carries state, which is what the two migrations need of it.
+        assert_eq!(append_item("", "done", true), "- [x] done");
+    }
+
+    #[test]
+    fn strip_marker_names_a_list_only_note() {
+        assert_eq!(strip_marker("- [x] milk"), "milk");
+        assert_eq!(strip_marker("just prose"), "just prose");
+    }
+
+    #[test]
+    fn render_item_is_what_extract_reads_back() {
+        assert_eq!(render_item("milk", false), "- [ ] milk");
+        assert_eq!(render_item("done", true), "- [x] done");
+        // An empty item has no trailing space, so a round trip does not grow it.
+        assert_eq!(render_item("", false), "- [ ]");
+        let line = render_item("milk", true);
+        assert_eq!(extract_items(&line), vec![item("milk", true, 0)]);
+    }
+
+    #[test]
+    fn items_carry_the_line_they_sit_on() {
+        let found = extract_items("a\n- [ ] x\nb\n- [x] y");
+        assert_eq!(found.iter().map(|i| i.line).collect::<Vec<_>>(), vec![1, 3]);
+    }
+
+    #[test]
+    fn a_stale_index_does_nothing() {
+        // The index comes from a UI that may be a moment behind the store. A tap
+        // that arrives late should be inert, not fatal.
+        let body = "- [ ] only";
+        assert_eq!(set_item_checked(body, 7, true), body);
+        assert_eq!(remove_item(body, 7), body);
+        assert_eq!(set_item_text(body, 7, "x"), body);
+    }
+
+    #[test]
+    fn a_plain_body_is_returned_byte_identical() {
+        let body = "just prose\nwith two lines";
+        assert_eq!(set_item_checked(body, 0, true), body);
+        assert_eq!(set_item_text(body, 0, "x"), body);
+        assert_eq!(remove_item(body, 0), body);
+    }
+
+    #[test]
+    fn round_trip_is_stable() {
+        let body = "- [ ] a\n- [x] b\n- [ ] c";
+        let items = extract_items(body);
+        // Ticking and unticking returns the original bytes.
+        let touched = set_item_checked(&set_item_checked(body, 0, true), 0, false);
+        assert_eq!(touched, body);
+        assert_eq!(extract_items(&touched), items);
+    }
 }

core/src/local/schema.rs

@@ -6,7 +6,9 @@
 //!
 //! Migrations are gated on `PRAGMA user_version`; bump it and add a block per change.
 
-use rusqlite::Connection;
+use rusqlite::{params, Connection, OptionalExtension};
+
+use crate::local::derive;
 
 const SCHEMA_V1: &str = r#"
 CREATE TABLE notes (
@@ -54,6 +56,8 @@ CREATE TABLE checklist_items (
     position  INTEGER NOT NULL DEFAULT 0
 );
 CREATE INDEX idx_items_note ON checklist_items (note_id);
+-- Both dropped in v8; kept here so an existing database has something to migrate
+-- FROM, exactly as `kind` above is kept for v6.
 
 CREATE TABLE attachments (
     id        TEXT PRIMARY KEY,
@@ -180,6 +184,71 @@ ALTER TABLE notes DROP COLUMN title;
 ALTER TABLE note_revisions DROP COLUMN title;
 "#;
 
+// v8 (M304): `checklist_items` is gone. The body IS the checklist — a `- [ ] milk`
+// line is the item — so a list can sit between two paragraphs instead of only after
+// them, which a side table could never express no matter how it was styled.
+//
+// Rust rather than a SQL const, for two reasons. The fold has to produce EXACTLY what
+// `derive::append_item` produces, and expressing that in SQL would be a second
+// implementation of the layout rule. And `group_concat` only gained a guaranteed
+// ORDER BY in SQLite 3.44 — a checklist that silently reordered itself during the
+// migration would be a poor way to find that out.
+//
+// `updated_at` and `dirty` are deliberately NOT touched. The server's Alembic
+// migration folds the same rows with the same spacing, so both sides land on
+// identical bodies and this needs no sync at all; marking every note dirty would
+// push a body the server already has, and would do it for every device at once.
+fn migrate_v8(conn: &Connection) -> rusqlite::Result<()> {
+    // Grouped in one pass — the query is ordered by note, so a change of note_id is
+    // the group boundary. `rowid` breaks ties, because `position` was only ever
+    // advisory and two rows sharing one is not a reason to reorder someone's list.
+    let mut grouped: Vec<(String, Vec<(String, bool)>)> = Vec::new();
+    {
+        let mut stmt = conn.prepare(
+            "SELECT note_id, text, checked FROM checklist_items
+             ORDER BY note_id ASC, position ASC, rowid ASC",
+        )?;
+        let mut rows = stmt.query([])?;
+        while let Some(row) = rows.next()? {
+            let note_id: String = row.get(0)?;
+            let text: String = row.get(1)?;
+            let checked: bool = row.get(2)?;
+            match grouped.last_mut() {
+                Some((id, items)) if *id == note_id => items.push((text, checked)),
+                _ => grouped.push((note_id, vec![(text, checked)])),
+            }
+        }
+    }
+
+    for (note_id, items) in grouped {
+        let existing: Option<String> = conn
+            .query_row("SELECT body FROM notes WHERE id = ?1", [&note_id], |r| {
+                r.get(0)
+            })
+            .optional()?;
+        // An item whose note is already gone has nothing to fold into. The foreign key
+        // should make this impossible; skipping costs nothing, and failing here would
+        // leave the only copy of someone's notes half-migrated.
+        let mut body = match existing {
+            Some(b) => b,
+            None => continue,
+        };
+        for (text, checked) in items {
+            body = derive::append_item(&body, &text, checked);
+        }
+        conn.execute(
+            "UPDATE notes SET body = ?1 WHERE id = ?2",
+            params![body, note_id],
+        )?;
+    }
+
+    conn.execute_batch(
+        "DROP INDEX IF EXISTS idx_items_note;
+         DROP TABLE checklist_items;",
+    )?;
+    Ok(())
+}
+
 /// Bring the database up to the latest schema. Idempotent.
 pub fn migrate(conn: &Connection) -> rusqlite::Result<()> {
     conn.execute_batch("PRAGMA foreign_keys = ON;")?;
@@ -212,5 +281,124 @@ pub fn migrate(conn: &Connection) -> rusqlite::Result<()> {
         conn.execute_batch(SCHEMA_V7)?;
         conn.execute_batch("PRAGMA user_version = 7;")?;
     }
+    if version < 8 {
+        migrate_v8(conn)?;
+        conn.execute_batch("PRAGMA user_version = 8;")?;
+    }
     Ok(())
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    /// A database as it stood before M304 — items still in their own table.
+    fn v7_db() -> Connection {
+        let conn = Connection::open_in_memory().expect("open");
+        conn.execute_batch("PRAGMA foreign_keys = ON;").expect("fk");
+        for batch in [
+            SCHEMA_V1, SCHEMA_V2, SCHEMA_V3, SCHEMA_V4, SCHEMA_V5, SCHEMA_V6, SCHEMA_V7,
+        ] {
+            conn.execute_batch(batch).expect("batch");
+        }
+        conn.execute_batch("PRAGMA user_version = 7;").expect("v7");
+        conn
+    }
+
+    fn add_note(conn: &Connection, id: &str, body: &str) {
+        conn.execute(
+            "INSERT INTO notes (id, body, created_at, updated_at)
+             VALUES (?1, ?2, '2026-01-01T00:00:00.000Z', '2026-01-01T00:00:00.000Z')",
+            params![id, body],
+        )
+        .expect("note");
+    }
+
+    fn add_item(conn: &Connection, note: &str, text: &str, checked: bool, pos: i64) {
+        conn.execute(
+            "INSERT INTO checklist_items (id, note_id, text, checked, position)
+             VALUES (?1, ?2, ?3, ?4, ?5)",
+            params![format!("{note}-{pos}"), note, text, checked, pos],
+        )
+        .expect("item");
+    }
+
+    fn body_of(conn: &Connection, id: &str) -> String {
+        conn.query_row("SELECT body FROM notes WHERE id = ?1", [id], |r| r.get(0))
+            .expect("body")
+    }
+
+    #[test]
+    fn v8_folds_items_into_the_body() {
+        let conn = v7_db();
+        add_note(&conn, "n1", "shopping");
+        add_item(&conn, "n1", "milk", false, 0);
+        add_item(&conn, "n1", "eggs", true, 1);
+
+        migrate(&conn).expect("migrate");
+
+        // Prose, blank line, list — the layout _note_markdown already exports, so an
+        // export taken before this migration and one taken after agree byte for byte.
+        assert_eq!(body_of(&conn, "n1"), "shopping\n\n- [ ] milk\n- [x] eggs");
+    }
+
+    #[test]
+    fn v8_keeps_a_list_only_note_whole() {
+        let conn = v7_db();
+        add_note(&conn, "n1", "");
+        add_item(&conn, "n1", "milk", false, 0);
+
+        migrate(&conn).expect("migrate");
+
+        assert_eq!(body_of(&conn, "n1"), "- [ ] milk");
+    }
+
+    #[test]
+    fn v8_leaves_timestamps_alone() {
+        // The whole reason this needs no sync: the server folds the same rows the same
+        // way, so both sides already agree. Marking notes dirty would push a body the
+        // server has, from every device at once.
+        let conn = v7_db();
+        add_note(&conn, "n1", "note");
+        add_item(&conn, "n1", "milk", false, 0);
+
+        migrate(&conn).expect("migrate");
+
+        let (updated, dirty): (String, i64) = conn
+            .query_row(
+                "SELECT updated_at, dirty FROM notes WHERE id = 'n1'",
+                [],
+                |r| Ok((r.get(0)?, r.get(1)?)),
+            )
+            .expect("row");
+        assert_eq!(updated, "2026-01-01T00:00:00.000Z");
+        assert_eq!(dirty, 1); // as inserted, not raised by the migration
+    }
+
+    #[test]
+    fn v8_drops_the_table_and_is_idempotent() {
+        let conn = v7_db();
+        add_note(&conn, "n1", "note");
+        migrate(&conn).expect("migrate");
+        migrate(&conn).expect("again");
+
+        let exists: i64 = conn
+            .query_row(
+                "SELECT COUNT(*) FROM sqlite_master WHERE type='table' AND name='checklist_items'",
+                [],
+                |r| r.get(0),
+            )
+            .expect("count");
+        assert_eq!(exists, 0);
+    }
+
+    #[test]
+    fn a_fresh_database_reaches_v8() {
+        let conn = Connection::open_in_memory().expect("open");
+        migrate(&conn).expect("migrate");
+        let version: i64 = conn
+            .query_row("PRAGMA user_version", [], |r| r.get(0))
+            .expect("version");
+        assert_eq!(version, 8);
+    }
+}

core/src/local/store.rs

@@ -9,7 +9,7 @@
 
 use chrono::{DateTime, Duration, SecondsFormat, Utc};
 use rusqlite::{params, params_from_iter, Connection, OptionalExtension};
-use serde_json::Value;
+use serde_json::{json, Value};
 use uuid::Uuid;
 
 use crate::local::derive;
@@ -24,24 +24,25 @@ fn new_id() -> String {
     Uuid::new_v4().to_string()
 }
 
-/// The note's NAME: its first non-blank body line, else its first checklist item.
+/// The note's NAME: the first line of its body that says anything.
 ///
 /// Mirrors `derive_display_title` in the server's notes/helpers.py — one rule written
 /// twice, and they have to agree or a synced note is called different things on either
 /// side of the wire.
 ///
-/// Pure, and given the items rather than fetching them: every caller has already
-/// loaded them, so a query here would be a second trip for something already in hand.
-fn display_title(body: &str, items: &[ChecklistItem]) -> String {
-    if let Some(line) = body.lines().map(str::trim).find(|l| !l.is_empty()) {
-        return line.to_string();
+/// It no longer needs the items, because the items ARE lines of the body now (M304).
+/// What it needs instead is to strip the task marker off: a list-only note is still
+/// named by its first item, and calling that note "- [ ] milk" would be showing
+/// someone the storage rather than the note. An empty item is skipped rather than
+/// naming the note "", which is what a half-typed list would otherwise do.
+fn display_title(body: &str) -> String {
+    for line in body.lines() {
+        let text = derive::strip_marker(line.trim()).trim();
+        if !text.is_empty() {
+            return text.to_string();
         }
-    items
-        .iter()
-        .map(|i| i.text.trim())
-        .find(|t| !t.is_empty())
-        .unwrap_or("")
-        .to_string()
+    }
+    String::new()
 }
 
 fn escape_like(s: &str) -> String {
@@ -69,19 +70,24 @@ fn load_labels(conn: &Connection, note_id: &str) -> rusqlite::Result<Vec<NoteLab
     rows.collect()
 }
 
-fn load_items(conn: &Connection, note_id: &str) -> rusqlite::Result<Vec<ChecklistItem>> {
-    let mut stmt = conn.prepare(
-        "SELECT id, text, checked, position FROM checklist_items WHERE note_id = ?1 ORDER BY position ASC",
-    )?;
-    let rows = stmt.query_map([note_id], |r| {
-        Ok(ChecklistItem {
-            id: r.get(0)?,
-            text: r.get(1)?,
-            checked: r.get(2)?,
-            position: r.get(3)?,
+/// The note's checklist, read out of its body. No query, because there is no table.
+///
+/// A `- [ ] milk` line IS the item (M304). The id is the item's ORDINAL rather than a
+/// uuid — which is all it ever amounted to anyway, since `push.rs` sent text and
+/// checked and never an id, and both sides replaced the whole list on every sync. It
+/// is also exactly what the rewriters in `derive` take, so a UI holding an id can act
+/// on it directly.
+fn items_of(body: &str) -> Vec<ChecklistItem> {
+    derive::extract_items(body)
+        .into_iter()
+        .enumerate()
+        .map(|(i, item)| ChecklistItem {
+            id: i.to_string(),
+            text: item.text,
+            checked: item.checked,
+            position: i as i64,
         })
-    })?;
-    rows.collect()
+        .collect()
 }
 
 fn load_attachments(conn: &Connection, note_id: &str) -> rusqlite::Result<Vec<Attachment>> {
@@ -162,11 +168,10 @@ fn load_note(conn: &Connection, id: &str) -> rusqlite::Result<Note> {
         },
     )?;
     note.labels = load_labels(conn, id)?;
-    note.items = load_items(conn, id)?;
+    note.items = items_of(&note.body);
     note.attachments = load_attachments(conn, id)?;
     note.previews = load_previews(conn, id)?;
-    // After the items, because a body-only-empty note is named by its first one.
-    note.display_title = display_title(&note.body, &note.items);
+    note.display_title = display_title(&note.body);
     Ok(note)
 }
 
@@ -358,23 +363,62 @@ pub fn create_note(conn: &Connection, input: &NoteCreateInput) -> rusqlite::Resu
         [],
         |r| r.get(0),
     )?;
+    // Items fold into the body rather than into rows of their own. Callers still hand
+    // them over separately — the importer has a list, not a blob — but where they end
+    // up is one place.
+    let mut body = input.body.clone();
+    if let Some(items) = &input.items {
+        for text in items {
+            body = derive::append_item(&body, text, false);
+        }
+    }
     conn.execute(
         "INSERT INTO notes (id, body, color, position, created_at, updated_at, dirty)
          VALUES (?1, ?2, ?3, ?4, ?5, ?5, 1)",
-        params![id, input.body, input.color, position, ts],
+        params![id, body, input.color, position, ts],
     )?;
-    if let Some(items) = &input.items {
-        for (i, text) in items.iter().enumerate() {
-            conn.execute(
-                "INSERT INTO checklist_items (id, note_id, text, position) VALUES (?1, ?2, ?3, ?4)",
-                params![new_id(), id, text, i as i64],
-            )?;
-        }
-    }
-    sync_tags(conn, &id, &input.body)?;
+    // The FOLDED body, not the input one: an item can carry a #tag too.
+    sync_tags(conn, &id, &body)?;
     load_note(conn, &id)
 }
 
+/// How long one editing session is assumed to last.
+///
+/// Inside this window a note's body may be written any number of times and only the
+/// FIRST write snapshots. That is what makes an idle-debounced autosave affordable:
+/// a write costs a write, not a write plus a revision.
+const REVISION_WINDOW_MINUTES: i64 = 10;
+
+/// Whether a body change earns a snapshot of the pre-edit body.
+///
+/// Two conditions. The body must actually differ — re-saving identical text is not a
+/// version of anything. And the note must not already carry a revision from this
+/// editing session.
+///
+/// The session rule is what keeps version history worth reading. Because
+/// [`snapshot_revision`] stores the body as it was BEFORE the edit, the first write
+/// of a session captures the note as you found it, and every write after it inside
+/// the window adds nothing. One revision per sitting falls out of the window on its
+/// own — no "commit" the client has to declare, and no protocol surface to carry it,
+/// which matters because sync-apply takes this same path.
+fn should_snapshot(conn: &Connection, id: &str, new_body: &str) -> rusqlite::Result<bool> {
+    let current: String =
+        conn.query_row("SELECT body FROM notes WHERE id = ?1", [id], |r| r.get(0))?;
+    if current == new_body {
+        return Ok(false);
+    }
+    // String comparison, not date maths: timestamps are RFC3339 UTC with a fixed
+    // millisecond field (see the module header), so lexical order IS chronological.
+    let cutoff = (Utc::now() - Duration::minutes(REVISION_WINDOW_MINUTES))
+        .to_rfc3339_opts(SecondsFormat::Millis, true);
+    let recent: i64 = conn.query_row(
+        "SELECT COUNT(*) FROM note_revisions WHERE note_id = ?1 AND created_at >= ?2",
+        params![id, cutoff],
+        |r| r.get(0),
+    )?;
+    Ok(recent == 0)
+}
+
 fn snapshot_revision(conn: &Connection, id: &str) -> rusqlite::Result<()> {
     let body: String =
         conn.query_row("SELECT body FROM notes WHERE id = ?1", [id], |r| r.get(0))?;
@@ -391,10 +435,13 @@ pub fn update_note(conn: &Connection, id: &str, changes: &Value) -> rusqlite::Re
         .as_object()
         .ok_or_else(|| rusqlite::Error::InvalidParameterName("changes must be an object".into()))?;
 
-    // Snapshot the pre-edit body before changing it (version history).
-    if obj.contains_key("body") {
+    // Snapshot the pre-edit body before changing it (version history) — but only
+    // once per editing session, and only if it actually changed. See should_snapshot.
+    if let Some(body) = obj.get("body").and_then(|v| v.as_str()) {
+        if should_snapshot(conn, id, body)? {
             snapshot_revision(conn, id)?;
         }
+    }
 
     for (k, v) in obj {
         match k.as_str() {
@@ -508,18 +555,32 @@ pub fn set_labels(conn: &Connection, id: &str, label_ids: &[String]) -> rusqlite
     load_note(conn, id)
 }
 
+// ---- checklist items: every one of these is a body edit ---------------------
+//
+// They keep their own names and signatures because the FFI, the Tauri commands and
+// the REST shape all speak in items, and a checklist is still a thing a note HAS.
+// What changed is where it is kept. Routing all three through `update_note` rather
+// than writing the body directly is what gives them revision snapshotting, `#tag`
+// re-derivation and the dirty/updated_at bookkeeping without any of it being
+// written a second time here.
+
+fn note_body(conn: &Connection, id: &str) -> rusqlite::Result<String> {
+    conn.query_row("SELECT body FROM notes WHERE id = ?1", [id], |r| r.get(0))
+}
+
+/// An item's id is its ordinal (see [items_of]). Anything else is a stale id from a
+/// UI that has not reloaded, and the right answer to those is to do nothing.
+fn item_index(item_id: &str) -> Option<usize> {
+    item_id.parse::<usize>().ok()
+}
+
+fn set_body(conn: &Connection, id: &str, body: String) -> rusqlite::Result<Note> {
+    update_note(conn, id, &json!({ "body": body }))
+}
+
 pub fn add_item(conn: &Connection, id: &str, text: &str) -> rusqlite::Result<Note> {
-    let pos: i64 = conn.query_row(
-        "SELECT COALESCE(MAX(position), -1) + 1 FROM checklist_items WHERE note_id = ?1",
-        [id],
-        |r| r.get(0),
-    )?;
-    conn.execute(
-        "INSERT INTO checklist_items (id, note_id, text, position) VALUES (?1, ?2, ?3, ?4)",
-        params![new_id(), id, text, pos],
-    )?;
-    touch(conn, id)?;
-    load_note(conn, id)
+    let body = note_body(conn, id)?;
+    set_body(conn, id, derive::append_item(&body, text, false))
 }
 
 pub fn update_item(
@@ -528,29 +589,27 @@ pub fn update_item(
     item_id: &str,
     changes: &Value,
 ) -> rusqlite::Result<Note> {
+    let index = match item_index(item_id) {
+        Some(i) => i,
+        None => return load_note(conn, id),
+    };
+    let mut body = note_body(conn, id)?;
     if let Some(text) = changes.get("text").and_then(Value::as_str) {
-        conn.execute(
-            "UPDATE checklist_items SET text = ?1 WHERE id = ?2 AND note_id = ?3",
-            params![text, item_id, id],
-        )?;
+        body = derive::set_item_text(&body, index, text);
     }
     if let Some(checked) = changes.get("checked").and_then(Value::as_bool) {
-        conn.execute(
-            "UPDATE checklist_items SET checked = ?1 WHERE id = ?2 AND note_id = ?3",
-            params![checked, item_id, id],
-        )?;
+        body = derive::set_item_checked(&body, index, checked);
     }
-    touch(conn, id)?;
-    load_note(conn, id)
+    set_body(conn, id, body)
 }
 
 pub fn delete_item(conn: &Connection, id: &str, item_id: &str) -> rusqlite::Result<Note> {
-    conn.execute(
-        "DELETE FROM checklist_items WHERE id = ?1 AND note_id = ?2",
-        params![item_id, id],
-    )?;
-    touch(conn, id)?;
-    load_note(conn, id)
+    let index = match item_index(item_id) {
+        Some(i) => i,
+        None => return load_note(conn, id),
+    };
+    let body = note_body(conn, id)?;
+    set_body(conn, id, derive::remove_item(&body, index))
 }
 
 pub fn delete_attachment(conn: &Connection, id: &str, att_id: &str) -> rusqlite::Result<Note> {

core/src/sync/compat.rs

@@ -19,11 +19,11 @@
 use serde::{Deserialize, Serialize};
 
 /// The sync wire protocol this client speaks.
-pub const CLIENT_PROTOCOL_VERSION: u32 = 2;
+pub const CLIENT_PROTOCOL_VERSION: u32 = 3;
 
 /// The oldest server protocol this client can drive — the symmetric half of the
 /// server's `min_client_protocol_version`.
-pub const MIN_SERVER_PROTOCOL_VERSION: u32 = 2;
+pub const MIN_SERVER_PROTOCOL_VERSION: u32 = 3;
 
 /// Capabilities without which syncing is meaningless, so their absence BLOCKS the
 /// link rather than degrading it.

core/src/sync/pull.rs

@@ -277,34 +277,12 @@ fn upsert_note(conn: &Connection, note: &wire::Note) -> rusqlite::Result<()> {
     // Children are replaced wholesale: a delta carries the note's FULL current state,
     // so "what the server sent" IS the complete set. Diffing would be more code and
     // could leave behind a row the server no longer has.
-    replace_items(conn, note)?;
     replace_attachments(conn, note)?;
     replace_previews(conn, note)?;
     replace_labels(conn, note)?;
     Ok(())
 }
 
-fn replace_items(conn: &Connection, note: &wire::Note) -> rusqlite::Result<()> {
-    conn.execute(
-        "DELETE FROM checklist_items WHERE note_id = ?1",
-        params![note.id],
-    )?;
-    for (index, item) in note.items.iter().enumerate() {
-        conn.execute(
-            "INSERT INTO checklist_items (id, note_id, text, checked, position)
-                  VALUES (?1, ?2, ?3, ?4, ?5)",
-            params![
-                item.id,
-                note.id,
-                item.text,
-                item.checked,
-                position_of(item.position, index)
-            ],
-        )?;
-    }
-    Ok(())
-}
-
 fn replace_attachments(conn: &Connection, note: &wire::Note) -> rusqlite::Result<()> {
     conn.execute(
         "DELETE FROM attachments WHERE note_id = ?1",
@@ -393,16 +371,6 @@ fn ensure_label_stub(conn: &Connection, label: &wire::NoteLabel) -> rusqlite::Re
     Ok(())
 }
 
-/// Trust an explicit position; fall back to arrival order when the server sent 0 for
-/// everything (which is what an unordered list looks like on the wire).
-fn position_of(explicit: i64, index: usize) -> i64 {
-    if explicit > 0 {
-        explicit
-    } else {
-        index as i64
-    }
-}
-
 /// Loop the feed to exhaustion, starting from the persisted cursor.
 ///
 /// NOTE ON ORDERING: the full cycle is push-then-pull (docs/sync.md). Running this
@@ -508,12 +476,22 @@ mod tests {
             sync_revision: revision,
             purged_at: None,
             labels: vec![],
-            items: vec![],
             attachments: vec![],
             previews: vec![],
         }
     }
 
+    fn attachment(id: &str) -> wire::Attachment {
+        wire::Attachment {
+            id: id.to_string(),
+            url: "/blob/x".into(),
+            filename: None,
+            mime: "image/png".into(),
+            size: None,
+            sha256: None,
+        }
+    }
+
     fn page(notes: Vec<wire::Note>, labels: Vec<wire::Label>, cursor: i64) -> wire::ChangesPage {
         wire::ChangesPage {
             notes,
@@ -612,35 +590,20 @@ mod tests {
 
     #[test]
     fn children_are_replaced_not_merged() {
+        // Was written over checklist items; they are lines of the body now (M304), so
+        // attachments carry the point instead. It is the same property either way: a
+        // delta is the note's FULL current state, so a child the server dropped has to
+        // disappear locally rather than linger.
         let conn = db();
         let mut first = note("n1", 1);
-        first.items = vec![
-            wire::Item {
-                id: "i1".into(),
-                text: "one".into(),
-                checked: false,
-                position: 0,
-            },
-            wire::Item {
-                id: "i2".into(),
-                text: "two".into(),
-                checked: false,
-                position: 1,
-            },
-        ];
+        first.attachments = vec![attachment("a1"), attachment("a2")];
         apply_page(&conn, &page(vec![first], vec![], 1)).expect("apply");
-        assert_eq!(count(&conn, "SELECT COUNT(*) FROM checklist_items"), 2);
+        assert_eq!(count(&conn, "SELECT COUNT(*) FROM attachments"), 2);
 
-        // The server dropped an item; the local copy must drop it too.
         let mut second = note("n1", 2);
-        second.items = vec![wire::Item {
-            id: "i1".into(),
-            text: "one".into(),
-            checked: true,
-            position: 0,
-        }];
+        second.attachments = vec![attachment("a1")];
         apply_page(&conn, &page(vec![second], vec![], 2)).expect("apply");
-        assert_eq!(count(&conn, "SELECT COUNT(*) FROM checklist_items"), 1);
+        assert_eq!(count(&conn, "SELECT COUNT(*) FROM attachments"), 1);
     }
 
     #[test]
@@ -810,23 +773,10 @@ mod tests {
     fn a_page_that_fails_leaves_the_cursor_untouched() {
         // Atomicity is the whole resumability story: a cursor committed ahead of its
         // data would skip those rows forever. Force a failure with a duplicate
-        // checklist-item id inside one page.
+        // attachment id inside one page.
         let conn = db();
         let mut n = note("n1", 3);
-        n.items = vec![
-            wire::Item {
-                id: "dup".into(),
-                text: "one".into(),
-                checked: false,
-                position: 0,
-            },
-            wire::Item {
-                id: "dup".into(),
-                text: "two".into(),
-                checked: false,
-                position: 1,
-            },
-        ];
+        n.attachments = vec![attachment("dup"), attachment("dup")];
         assert!(apply_page(&conn, &page(vec![n], vec![], 3)).is_err());
         assert_eq!(state::read(&conn).expect("state").last_cursor, 0);
         assert_eq!(count(&conn, "SELECT COUNT(*) FROM notes"), 0);

core/src/sync/push.rs

@@ -79,8 +79,6 @@ pub struct Change {
     #[serde(skip_serializing_if = "Option::is_none")]
     pub position: Option<i64>,
     #[serde(skip_serializing_if = "Option::is_none")]
-    pub items: Option<Vec<ItemOut>>,
-    #[serde(skip_serializing_if = "Option::is_none")]
     pub label_ids: Option<Vec<String>>,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub created_at: Option<String>,
@@ -103,7 +101,6 @@ impl Change {
             remind_at: None,
             recurrence: None,
             position: None,
-            items: None,
             label_ids: None,
             created_at: None,
             name: None,
@@ -111,12 +108,6 @@ impl Change {
     }
 }
 
-#[derive(Debug, Serialize)]
-pub struct ItemOut {
-    pub text: String,
-    pub checked: bool,
-}
-
 // --- incoming results --------------------------------------------------------
 
 #[derive(Debug, Deserialize)]
@@ -201,7 +192,6 @@ fn collect_labels(conn: &Connection, out: &mut Vec<Change>, limit: usize) -> rus
             remind_at: None,
             recurrence: None,
             position: None,
-            items: None,
             label_ids: None,
             created_at: None,
         })
@@ -267,19 +257,6 @@ fn note_row(conn: &Connection, id: &str) -> rusqlite::Result<NoteRow> {
 fn note_change(conn: &Connection, id: &str) -> rusqlite::Result<Change> {
     let row = note_row(conn, id)?;
 
-    let items = {
-        let mut stmt = conn.prepare(
-            "SELECT text, checked FROM checklist_items WHERE note_id = ?1 ORDER BY position",
-        )?;
-        let rows = stmt.query_map(params![id], |r| {
-            Ok(ItemOut {
-                text: r.get(0)?,
-                checked: r.get::<_, i64>(1)? != 0,
-            })
-        })?;
-        rows.collect::<rusqlite::Result<Vec<ItemOut>>>()?
-    };
-
     // MANUAL memberships only. Tag-sourced ones (`via_tag = 1`) are re-derived by the
     // server from the body; sending them as label_ids would convert them into manual
     // assignments that no longer disappear when the #tag is removed from the text.
@@ -305,7 +282,6 @@ fn note_change(conn: &Connection, id: &str) -> rusqlite::Result<Change> {
         remind_at: row.remind_at,
         recurrence: row.recurrence,
         position: Some(row.position),
-        items: Some(items),
         label_ids: Some(label_ids),
         created_at: Some(row.created_at),
         name: None,

core/src/sync/wire.rs

@@ -58,8 +58,6 @@ pub struct Note {
     #[serde(default)]
     pub labels: Vec<NoteLabel>,
     #[serde(default)]
-    pub items: Vec<Item>,
-    #[serde(default)]
     pub attachments: Vec<Attachment>,
     #[serde(default)]
     pub previews: Vec<Preview>,
@@ -87,17 +85,6 @@ pub struct NoteLabel {
     pub via_tag: bool,
 }
 
-#[derive(Debug, Clone, Deserialize)]
-pub struct Item {
-    pub id: String,
-    #[serde(default)]
-    pub text: String,
-    #[serde(default)]
-    pub checked: bool,
-    #[serde(default)]
-    pub position: i64,
-}
-
 #[derive(Debug, Clone, Deserialize)]
 pub struct Attachment {
     pub id: String,

frontend/src/components/AppShell.vue

@@ -14,7 +14,7 @@ import ImportNotes from "./ImportNotes.vue";
 import LabelsModal from "./LabelsModal.vue";
 import { isDesktop } from "../desktop/bridge";
 import { facetsToQuery } from "../notes/facets";
-import { NOTE_SWATCH_CLASSES, type NoteColor } from "../notes/colors";
+import { NOTE_SWATCH_CLASSES, resolveLabelColor } from "../notes/colors";
 
 const route = useRoute();
 const router = useRouter();
@@ -173,8 +173,10 @@ onBeforeUnmount(() => {
 
 const currentLabelId = computed(() => (route.name === "label" ? String(route.params.id) : null));
 
-function labelDot(color: string): string {
-  return NOTE_SWATCH_CLASSES[color as NoteColor] ?? NOTE_SWATCH_CLASSES.default;
+// The drawer's tag list. Same resolution as every other chip and dot — a tag that is
+// green on a card must be green here, or the sidebar stops being a way to find it.
+function labelDot(label: { name: string; color: string }): string {
+  return NOTE_SWATCH_CLASSES[resolveLabelColor(label)] ?? NOTE_SWATCH_CLASSES.default;
 }
 
 // The board lenses — the routes a search can happen *within*. Searching while looking
@@ -443,7 +445,7 @@ async function signOut() {
           >
             <span
               class="h-2.5 w-2.5 shrink-0 rounded-full border border-black/10 dark:border-white/15"
-              :class="labelDot(lb.color)"
+              :class="labelDot(lb)"
             ></span>
             <span class="truncate">{{ lb.name }}</span>
           </RouterLink>

frontend/src/components/LabelsModal.vue

@@ -1,7 +1,13 @@
 <script setup lang="ts">
 import { computed, ref } from "vue";
 import { useLabelsStore, type Label } from "../stores/labels";
-import { NOTE_COLOR_KEYS, NOTE_COLOR_LABELS, NOTE_SWATCH_CLASSES, type NoteColor } from "../notes/colors";
+import {
+  NOTE_COLOR_KEYS,
+  NOTE_COLOR_LABELS,
+  NOTE_SWATCH_CLASSES,
+  resolveLabelColor,
+  type NoteColor,
+} from "../notes/colors";
 import BaseModal from "./BaseModal.vue";
 import Icon from "./Icon.vue";
 
@@ -25,8 +31,12 @@ async function rename(id: string, value: string) {
   if (name) await labels.rename(id, name);
 }
 
-function labelDot(color: string): string {
-  return NOTE_SWATCH_CLASSES[color as NoteColor] ?? NOTE_SWATCH_CLASSES.default;
+// Shows the colour the tag ACTUALLY wears, derived from its name when nobody has
+// picked one — so this screen agrees with the chips everywhere else. The ring in the
+// swatch grid below follows the same resolution, so opening the picker highlights
+// what you can already see rather than nothing at all.
+function labelDot(label: { name: string; color: string }): string {
+  return NOTE_SWATCH_CLASSES[resolveLabelColor(label)] ?? NOTE_SWATCH_CLASSES.default;
 }
 
 function openColor(id: string) {
@@ -75,8 +85,8 @@ async function doMerge(sourceId: string, targetId: string) {
             <button
               type="button"
               class="h-4 w-4 shrink-0 rounded-full border border-black/10 transition hover:scale-110 focus:outline-none focus-visible:ring-2 focus-visible:ring-brand dark:border-white/15"
-              :class="labelDot(lb.color)"
-              :title="`Color: ${NOTE_COLOR_LABELS[(lb.color as NoteColor)] ?? lb.color}`"
+              :class="labelDot(lb)"
+              :title="`Color: ${NOTE_COLOR_LABELS[resolveLabelColor(lb)]}`"
               aria-label="Change label color"
               @click="openColor(lb.id)"
             />
@@ -120,7 +130,7 @@ async function doMerge(sourceId: string, targetId: string) {
                 :title="NOTE_COLOR_LABELS[key]"
                 :aria-label="NOTE_COLOR_LABELS[key]"
                 class="h-6 w-6 rounded-full border border-black/10 transition hover:scale-110 focus:outline-none focus-visible:ring-2 focus-visible:ring-brand"
-                :class="[NOTE_SWATCH_CLASSES[key], lb.color === key ? 'ring-2 ring-brand' : '']"
+                :class="[NOTE_SWATCH_CLASSES[key], resolveLabelColor(lb) === key ? 'ring-2 ring-brand' : '']"
                 @click="pickColor(lb.id, key)"
               />
             </div>
@@ -140,7 +150,7 @@ async function doMerge(sourceId: string, targetId: string) {
                   >
                     <span
                       class="h-2.5 w-2.5 shrink-0 rounded-full border border-black/10 dark:border-white/15"
-                      :class="labelDot(t.color)"
+                      :class="labelDot(t)"
                     ></span>
                     <span class="truncate">{{ t.name }}</span>
                   </button>

frontend/src/components/MarkdownText.vue

@@ -3,7 +3,12 @@ import { computed } from "vue";
 import { parseMarkdown } from "../notes/markdown";
 import MarkdownInline from "./MarkdownInline.vue";
 
-const props = defineProps<{ text: string }>();
+const props = defineProps<{ text: string; toggleable?: boolean }>();
+// Ticking a box rewrites a line of the note's body, which is a thing only the owner
+// of that note can do — so this renders the checkbox and hands the intent up rather
+// than reaching for the store itself. The card wires it; a read-only render does not
+// pass `toggleable` and the boxes are inert.
+const emit = defineEmits<{ toggle: [index: number, checked: boolean] }>();
 const blocks = computed(() => parseMarkdown(props.text));
 </script>
 
@@ -19,6 +24,28 @@ const blocks = computed(() => parseMarkdown(props.text));
       >
         <MarkdownInline :tokens="b.inline ?? []" />
       </blockquote>
+      <div v-else-if="b.type === 'task'" class="flex flex-col gap-1">
+        <div v-for="(it, j) in b.items ?? []" :key="j" class="flex items-start gap-2">
+          <!-- Not wrapped in a <label>: on a card the text is the note's own words and
+               clicking it opens the note, so only the box itself toggles. `.stop` for
+               the same reason — the card is a click target underneath. -->
+          <input
+            type="checkbox"
+            class="mt-0.5 h-4 w-4 shrink-0 accent-brand"
+            :checked="b.tasks?.[j]?.checked ?? false"
+            :disabled="!toggleable"
+            :aria-label="toggleable ? 'Toggle item' : undefined"
+            @click.stop
+            @change="emit('toggle', b.tasks?.[j]?.index ?? 0, ($event.target as HTMLInputElement).checked)"
+          />
+          <span
+            class="min-w-0 flex-1"
+            :class="b.tasks?.[j]?.checked ? 'text-neutral-400 line-through' : ''"
+          >
+            <MarkdownInline :tokens="it" />
+          </span>
+        </div>
+      </div>
       <ul v-else-if="b.type === 'ul'" class="list-disc space-y-0.5 pl-5">
         <li v-for="(it, j) in b.items ?? []" :key="j"><MarkdownInline :tokens="it" /></li>
       </ul>

frontend/src/components/NoteCard.vue

@@ -3,17 +3,18 @@ import { computed, onBeforeUnmount, ref, watch } from "vue";
 import { useNotesStore } from "../stores/notes";
 import {
   LABEL_CHIP_CLASSES,
-  NOTE_CARD_CLASSES,
   NOTE_COLOR_KEYS,
   NOTE_COLOR_LABELS,
   NOTE_SWATCH_CLASSES,
+  noteCardClasses,
+  noteTintVars,
+  resolveLabelColor,
   type NoteColor,
 } from "../notes/colors";
 import type { Note } from "../stores/notes";
 import Icon from "./Icon.vue";
 import LinkPreview from "./LinkPreview.vue";
 import MarkdownText from "./MarkdownText.vue";
-import NoteChecklist from "./NoteChecklist.vue";
 import {
   cardIdAt,
   draggingId,
@@ -94,6 +95,15 @@ const bodyPreview = computed(() => {
   return lines.slice(0, PREVIEW_LINES).join("\n") + "\n…";
 });
 
+/** Tick a box without opening the note — the common gesture on a board.
+ *
+ *  The index is the item's ordinal in the WHOLE body, which survives the preview
+ *  clamp above because that only ever drops lines from the end. `updateItem` takes
+ *  it as the item id, which is exactly what an id is now (M304). */
+function toggleTask(index: number, checked: boolean) {
+  void notes.updateItem(props.note.id, String(index), { checked });
+}
+
 const root = ref<HTMLElement | null>(null);
 
 // --- Drag-to-reorder. Pointer Events, gated behind an explicit grip handle so a
@@ -181,12 +191,10 @@ async function snoozeReminder(minutes: number): Promise<void> {
   emit("reminder-changed");
 }
 
-function cardClass(color: NoteColor): string {
-  return NOTE_CARD_CLASSES[color] ?? NOTE_CARD_CLASSES.default;
-}
-
-function labelChip(color: string): string {
-  return LABEL_CHIP_CLASSES[color as NoteColor] ?? LABEL_CHIP_CLASSES.default;
+// Takes the label, not its colour: a tag nobody has coloured derives one from its
+// name, so chips carry the tag's identity rather than all being the same grey.
+function labelChip(label: { name: string; color: string }): string {
+  return LABEL_CHIP_CLASSES[resolveLabelColor(label)] ?? LABEL_CHIP_CLASSES.default;
 }
 
 // Per-card color popover (recolor without opening the editor).
@@ -215,17 +223,60 @@ onBeforeUnmount(() => document.removeEventListener("mousedown", onDocMousedown))
 <template>
   <div
     ref="root"
-    class="group relative mb-4 break-inside-avoid rounded-xl border p-3 shadow-sm transition hover:shadow-md"
+    class="group relative mb-4 break-inside-avoid rounded-xl border border-[#b8b8b8] p-3 shadow-sm transition hover:shadow-md dark:border-[#404040]"
     :class="[
-      cardClass(note.color),
+      noteCardClasses(note),
       dragging ? 'opacity-40' : '',
       dragOver
         ? 'scale-[1.02] shadow-lg ring-2 ring-brand ring-offset-2 ring-offset-white dark:ring-offset-neutral-950'
         : '',
       active ? 'ring-2 ring-brand' : '',
     ]"
+    :style="noteTintVars(note)"
     :data-note-id="note.id"
   >
+    <!-- THE EDGE LIVES HERE, NOT IN THE PALETTE, and that is the whole point of it.
+         Every card gets the same grey hairline whatever colour it is; the fill is the
+         only thing that varies. The version of this that was a `{hue}-900` border
+         failed because the line was both the loudest element on the card (1.56-2.09
+         against its own fill, where the fill managed 1.03-1.05 against the board) AND
+         carried the same information the fill did, so a board of them read as a grid
+         of outlines. A neutral line carries no information at all, which is exactly
+         what lets it be structure.
+
+         The two values are MATCHED, not picked by eye: each measures ~1.6-1.7 against
+         the card it edges (light 1.57-1.98, dark 1.58-1.73), so the edge has the same
+         authority in either theme. #404040 is `neutral-700`, which is what the default
+         card's border always was — promoted from one entry in the palette to the rule
+         for all of them. #b8b8b8 sits between `neutral-300` and `neutral-400`, neither
+         of which lands in range: 300 fades out at 1.18 on a gray-tagged card, 400
+         jumps to 2.52 and reads as a wireframe.
+
+         NOT a translucent black/white edge, which is the tidier-looking way to do this
+         and was measured and rejected: a border composites over the card's own fill,
+         so `border-white/20` comes out #56396d on a purple card and #a3c9c1 on a teal
+         one. Hue-coded edges are the thing being removed.
+
+         `shadow-sm`, back down from `shadow`: the border is the boundary again, so the
+         shadow is only depth. -->
+    <!-- TAGS FIRST. They used to sit under everything else, which on a tall note put
+         the one thing that says what a note IS below the fold of a glance. A board is
+         scanned, not read, and the answer to "which of these is about the thing I am
+         looking for" should be the first thing the eye lands on rather than the last.
+
+         Above the image and the body rather than beside them, because the body's first
+         line is the note's NAME (M13 steps 3 and 4) and a chip floated next to it would
+         compete with the thing that identifies the note. -->
+    <div v-if="note.labels.length" class="mb-2 flex flex-wrap gap-1">
+      <span
+        v-for="lb in note.labels"
+        :key="lb.id"
+        class="rounded-full px-2 py-0.5 text-xs"
+        :class="labelChip(lb)"
+        >{{ lb.via_tag ? "#" + lb.name : lb.name }}</span
+      >
+    </div>
+
     <img
       v-if="firstImage"
       :src="firstImage.url"
@@ -263,7 +314,7 @@ onBeforeUnmount(() => document.removeEventListener("mousedown", onDocMousedown))
            blank and the link is never unreachable. -->
       <LinkPreview v-if="loneUrlPreview" :preview="loneUrlPreview" />
       <div v-else-if="note.body" class="text-sm text-neutral-700 dark:text-neutral-300">
-        <MarkdownText :text="bodyPreview" />
+        <MarkdownText :text="bodyPreview" toggleable @toggle="toggleTask" />
       </div>
       <p
         v-if="!note.body && !note.items.length && !note.attachments.length"
@@ -279,23 +330,10 @@ onBeforeUnmount(() => document.removeEventListener("mousedown", onDocMousedown))
       <LinkPreview v-for="p in note.previews" :key="p.id" :preview="p" compact />
     </div>
 
-    <NoteChecklist
-      v-if="note.items.length"
-      :class="note.body ? 'mt-2' : ''"
-      :note-id="note.id"
-      :items="note.items"
-      @click="emit('open', note)"
-    />
-
-    <div v-if="note.labels.length" class="mt-2 flex flex-wrap gap-1">
-      <span
-        v-for="lb in note.labels"
-        :key="lb.id"
-        class="rounded-full px-2 py-0.5 text-xs"
-        :class="labelChip(lb.color)"
-        >{{ lb.via_tag ? "#" + lb.name : lb.name }}</span
-      >
-    </div>
+    <!-- No separate checklist block any more. A checklist is lines of the body (M304),
+         so MarkdownText above draws it in place — which is what lets a list sit between
+         two paragraphs instead of always after them. Rendering both would have shown
+         every list twice. -->
 
     <div v-if="note.remind_at" class="mt-2 flex flex-wrap items-center gap-1.5">
       <span

frontend/src/components/NoteChecklist.vue

@@ -1,75 +0,0 @@
-<script setup lang="ts">
-import { ref } from "vue";
-import { useNotesStore, type ChecklistItem } from "../stores/notes";
-
-const props = defineProps<{ noteId: string; items: ChecklistItem[]; editable?: boolean }>();
-const notes = useNotesStore();
-const newItem = ref("");
-
-async function addItem() {
-  const text = newItem.value.trim();
-  if (!text) return;
-  await notes.addItem(props.noteId, text);
-  newItem.value = "";
-}
-
-function toggle(item: ChecklistItem) {
-  void notes.updateItem(props.noteId, item.id, { checked: !item.checked });
-}
-
-function editText(item: ChecklistItem, value: string) {
-  if (value !== item.text) void notes.updateItem(props.noteId, item.id, { text: value });
-}
-
-function remove(item: ChecklistItem) {
-  void notes.deleteItem(props.noteId, item.id);
-}
-</script>
-
-<template>
-  <div class="flex flex-col gap-1">
-    <div v-for="item in items" :key="item.id" class="group/item flex items-center gap-2">
-      <input
-        type="checkbox"
-        class="h-4 w-4 shrink-0 accent-brand"
-        :checked="item.checked"
-        @change="toggle(item)"
-        @click.stop
-      />
-      <input
-        v-if="editable"
-        :value="item.text"
-        class="min-w-0 flex-1 bg-transparent text-sm outline-none"
-        :class="item.checked ? 'text-neutral-400 line-through' : ''"
-        @change="editText(item, ($event.target as HTMLInputElement).value)"
-      />
-      <span
-        v-else
-        class="min-w-0 flex-1 truncate text-sm"
-        :class="item.checked ? 'text-neutral-400 line-through' : 'text-neutral-700 dark:text-neutral-300'"
-        >{{ item.text }}</span
-      >
-      <button
-        v-if="editable"
-        type="button"
-        class="hover-reveal text-neutral-300 opacity-0 hover:text-neutral-600 group-hover/item:opacity-100 dark:hover:text-neutral-200"
-        aria-label="Delete item"
-        @click="remove(item)"
-      >
-        ×
-      </button>
-    </div>
-
-    <form v-if="editable" class="mt-1 flex items-center gap-2" @submit.prevent="addItem">
-      <span class="h-4 w-4 shrink-0" />
-      <input
-        v-model="newItem"
-        type="text"
-        placeholder="+ List item"
-        class="min-w-0 flex-1 bg-transparent text-sm outline-none placeholder:text-neutral-400"
-      />
-    </form>
-
-    <p v-if="!editable && items.length === 0" class="text-sm italic text-neutral-400">Empty checklist</p>
-  </div>
-</template>

frontend/src/components/NoteEditor.vue

@@ -5,12 +5,19 @@ import ColorPicker from "./ColorPicker.vue";
 import Icon from "./Icon.vue";
 import LabelPicker from "./LabelPicker.vue";
 import LinkPreview from "./LinkPreview.vue";
-import NoteChecklist from "./NoteChecklist.vue";
 import { fromLocalInput, toLocalInput } from "../notes/datetime";
 import { takeMorphOrigin } from "../composables/useEditorMorph";
 import { prefersReducedMotion } from "../composables/useReducedMotion";
 import type { Note, NoteLabel, NoteRevision } from "../stores/notes";
-import { LABEL_CHIP_CLASSES, type NoteColor } from "../notes/colors";
+import { LABEL_CHIP_CLASSES, resolveLabelColor, type NoteColor } from "../notes/colors";
+import {
+  afterEnter,
+  type EditorBlock,
+  joinBlocks,
+  plusTask,
+  splitBlocks,
+  withoutIndex,
+} from "../notes/blocks";
 
 // One modal editor for BOTH composing and editing — a single surface (the board's
 // "Take a note…" bar just opens this in compose mode). `note` = the note being edited,
@@ -25,16 +32,49 @@ const emit = defineEmits<{ (e: "close"): void; (e: "navigate", id: string): void
 const notes = useNotesStore();
 
 const noteId = ref<string | null>(props.note?.id ?? null);
-const body = ref(props.note?.body ?? props.initialBody);
+// BLOCKS rather than one string, because a checklist item is drawn as a real checkbox
+// and a widget cannot live inside a <textarea>. The note is still one markdown body —
+// see notes/blocks.ts — and `body` is what every save, baseline and draft still reads.
+const blocks = ref<EditorBlock[]>(splitBlocks(props.note?.body ?? props.initialBody));
+const body = computed(() => joinBlocks(blocks.value));
+function setBody(text: string): void {
+  blocks.value = splitBlocks(text);
+}
 const color = ref<NoteColor>(props.note?.color ?? "default");
 const labelList = ref<NoteLabel[]>(props.note ? [...props.note.labels] : []);
 // Whether this editor is showing the checklist. A note HAS a checklist (M13 step 2)
 // rather than BEING one, so this is a view flag, not a property of the note: it turns
 // on when the note already carries items, and when someone asks for one.
-const checklistOpen = ref(false);
 const saving = ref(false);
 const root = ref<HTMLElement | null>(null);
-const bodyInput = ref<HTMLTextAreaElement | null>(null);
+// One element per block, keyed by the block's id — the only thing about a block that
+// survives one being inserted above it. Focus is asked for by id and honoured after
+// the render that created the field, since an element that does not exist yet cannot
+// take it.
+const blockEls = new Map<number, HTMLTextAreaElement | HTMLInputElement>();
+function setBlockEl(id: number, el: unknown): void {
+  if (el) blockEls.set(id, el as HTMLTextAreaElement);
+  else blockEls.delete(id);
+}
+async function focusBlock(id: number | null): Promise<void> {
+  if (id === null) return;
+  await nextTick();
+  const el = blockEls.get(id);
+  el?.focus();
+  if (el) el.selectionStart = el.selectionEnd = el.value.length;
+}
+
+/** A prose field sized to its text. `rows="1"` plus this beats guessing a row count,
+ *  which is wrong the moment a line wraps. */
+function grow(el: HTMLTextAreaElement): void {
+  el.style.height = "auto";
+  el.style.height = `${el.scrollHeight}px`;
+}
+function growAll(): void {
+  for (const el of blockEls.values()) {
+    if (el instanceof HTMLTextAreaElement) grow(el);
+  }
+}
 const fileInput = ref<HTMLInputElement | null>(null);
 const uploadError = ref("");
 
@@ -75,15 +115,6 @@ const liveNote = computed<Note>(() =>
     ? (notes.items.find((n) => n.id === noteId.value) ?? props.note ?? draftNote.value)
     : draftNote.value,
 );
-// The checklist renders once the note has items, or once someone has asked for one.
-// It sits BELOW the body rather than instead of it — a note can carry both, which is
-// the whole point of the merge.
-//
-// Items need a persisted note to hang off, so this is a rich action like attaching a
-// file: in compose it waits for the draft to be saved.
-const showChecklist = computed(
-  () => !isCreate.value && (liveNote.value.items.length > 0 || checklistOpen.value),
-);
 const bodyPlaceholder = "Take a note…";
 
 // Keep local state in sync when the edited note changes (modal reused for another note).
@@ -91,7 +122,7 @@ watch(
   () => props.note,
   (n) => {
     noteId.value = n?.id ?? null;
-    body.value = n?.body ?? "";
+    setBody(n?.body ?? "");
     color.value = (n?.color ?? "default") as NoteColor;
     labelList.value = n ? [...n.labels] : [];
     baseline.value = { body: n?.body ?? "", color: (n?.color ?? "default") as NoteColor };
@@ -142,10 +173,9 @@ async function flush(): Promise<void> {
 
 function resetCompose(): void {
   noteId.value = null;
-  body.value = "";
+  setBody("");
   color.value = "default";
   labelList.value = [];
-  checklistOpen.value = false;
   baseline.value = { body: "", color: "default" };
   uploadError.value = "";
 }
@@ -157,7 +187,9 @@ async function commitAndContinue(): Promise<void> {
   await flush();
   resetCompose();
   await nextTick();
-  bodyInput.value?.focus();
+  growAll();
+  const first = blocks.value[0];
+  await focusBlock(first ? first.id : null);
 }
 // ---- open/close animation (M7) ----
 //
@@ -227,21 +259,68 @@ function onBackdropMousedown(): void {
 
 onMounted(async () => {
   await nextTick();
-  const el = bodyInput.value;
-  el?.focus();
-  // Put the caret after any seeded text (type-to-compose) so typing continues cleanly.
-  if (el) el.selectionStart = el.selectionEnd = el.value.length;
+  growAll();
+  // The LAST block, with the caret after its text: opening a note means continuing it,
+  // and type-to-compose seeds text that should be typed straight on from.
+  const last = blocks.value[blocks.value.length - 1];
+  await focusBlock(last ? last.id : null);
 });
 
-function onBodyKeydown(e: KeyboardEvent) {
-  // Compose: Shift+Enter saves the note and starts a fresh one (rapid capture).
+/** Editing one block: replace its text, leave every other block alone. */
+function setText(index: number, text: string): void {
+  const out = [...blocks.value];
+  out[index] = { ...out[index], text };
+  blocks.value = out;
+}
+
+function setChecked(index: number, checked: boolean): void {
+  const out = [...blocks.value];
+  out[index] = { ...out[index], checked };
+  blocks.value = out;
+}
+
+function onProseInput(index: number, e: Event): void {
+  const el = e.target as HTMLTextAreaElement;
+  setText(index, el.value);
+  grow(el);
+}
+
+/** Compose: Shift+Enter saves the note and starts a fresh one (rapid capture). */
+function onProseKeydown(e: KeyboardEvent): void {
   if (isCreate.value && e.key === "Enter" && e.shiftKey) {
     e.preventDefault();
     void commitAndContinue();
-    return;
   }
 }
 
+/** Enter on an item makes the next one; on an EMPTY item it ends the list. */
+function onTaskEnter(index: number): void {
+  const next = afterEnter(blocks.value, index);
+  blocks.value = next.blocks;
+  void focusBlock(next.focus);
+}
+
+/**
+ * Backspace at the very start of an EMPTY item removes it.
+ *
+ * Worth having on the web where Android's is not: a browser sends a real keydown for
+ * Backspace, while an Android soft keyboard sends an IME delete that never surfaces as
+ * one. Enter-on-empty ends a list on both surfaces; this is the extra way out that
+ * only one of them can offer.
+ */
+function onTaskBackspace(index: number, e: KeyboardEvent): void {
+  const el = e.target as HTMLInputElement;
+  if (el.value !== "" || el.selectionStart !== 0) return;
+  e.preventDefault();
+  removeBlock(index);
+}
+
+function removeBlock(index: number): void {
+  const next = withoutIndex(blocks.value, index);
+  blocks.value = next.blocks;
+  void focusBlock(next.focus);
+}
+
 // ---- reminder ----
 const reminderLocal = computed(() => toLocalInput(liveNote.value.remind_at));
 async function onReminderChange(e: Event) {
@@ -279,20 +358,26 @@ async function onLabelsChange(next: NoteLabel[]) {
 async function removeLabel(id: string) {
   await onLabelsChange(labelList.value.filter((lb) => lb.id !== id));
 }
-function labelChip(c: string): string {
-  return LABEL_CHIP_CLASSES[c as NoteColor] ?? LABEL_CHIP_CLASSES.default;
+// Takes the label, not its colour — a tag nobody has coloured derives one from its
+// name. Must match NoteCard's chip exactly: the same tag either side of opening a
+// note changing colour would be worse than both being grey.
+function labelChip(label: { name: string; color: string }): string {
+  return LABEL_CHIP_CLASSES[resolveLabelColor(label)] ?? LABEL_CHIP_CLASSES.default;
 }
 
 // ---- add a checklist ----
 //
-// Not a conversion any more. Nothing is moved, nothing is swapped: the note keeps its
-// body and gains a place to put items. Persists the draft first for the same reason
-// attaching a file does — an item needs a note to belong to.
-async function addChecklist() {
-  if (checklistOpen.value) return;
-  const id = await ensureDraft();
-  if (!id) return;
-  checklistOpen.value = true;
+// Appends an empty item and puts the caret in it. Unlike every other toolbar button
+// this one needs NO persisted note to hang anything off — a checklist is part of the
+// body (M304), so it works on an empty compose box the moment it opens.
+//
+// Appends rather than inserting at the caret because a block editor has no single
+// caret to insert at: the field that had focus may not be the one being looked at by
+// the time this runs.
+function addChecklist(): void {
+  const next = plusTask(blocks.value);
+  blocks.value = next.blocks;
+  void focusBlock(next.focus);
 }
 
 // ---- attachments ----
@@ -371,7 +456,7 @@ async function restoreRevisionAt(revId: string) {
   const id = noteId.value;
   if (!id) return;
   const updated = await notes.restoreRevision(id, revId);
-  body.value = updated.body;
+  setBody(updated.body);
   color.value = updated.color;
   baseline.value = { body: updated.body, color: updated.color };
   void loadRevisions(); // the pre-restore state became a new revision
@@ -474,29 +559,59 @@ function revPreview(rev: NoteRevision): string {
           />
         </div>
 
+        <!-- The body, as fields and checkboxes rather than as markup. A checklist
+             item is a real input; a run of prose is one textarea, so typing a
+             paragraph still feels like typing a paragraph. -->
+        <div class="flex flex-col gap-1">
+          <template v-for="(block, i) in blocks" :key="block.id">
+            <div v-if="block.checked !== null" class="group/item flex items-center gap-2">
+              <input
+                type="checkbox"
+                class="h-4 w-4 shrink-0 accent-brand"
+                :checked="block.checked"
+                :aria-label="block.text || 'Checklist item'"
+                @change="setChecked(i, ($event.target as HTMLInputElement).checked)"
+              />
+              <input
+                :ref="(el) => setBlockEl(block.id, el)"
+                :value="block.text"
+                type="text"
+                class="min-w-0 flex-1 bg-transparent text-sm leading-relaxed outline-none"
+                :class="block.checked ? 'text-neutral-400 line-through' : ''"
+                @input="setText(i, ($event.target as HTMLInputElement).value)"
+                @keydown.enter.prevent="onTaskEnter(i)"
+                @keydown.backspace="onTaskBackspace(i, $event)"
+              />
+              <button
+                type="button"
+                class="hover-reveal shrink-0 text-neutral-300 opacity-0 hover:text-neutral-600 focus:opacity-100 group-hover/item:opacity-100 dark:hover:text-neutral-200"
+                aria-label="Delete item"
+                @click="removeBlock(i)"
+              >
+                ×
+              </button>
+            </div>
             <textarea
-          ref="bodyInput"
-          v-model="body"
-          rows="8"
-          :placeholder="bodyPlaceholder"
-          class="w-full resize-none bg-transparent text-sm leading-relaxed outline-none placeholder:text-neutral-400"
-          @keydown="onBodyKeydown"
-        />
-        <!-- Below the body, not instead of it. -->
-        <NoteChecklist
-          v-if="showChecklist"
-          class="py-1"
-          :note-id="liveNote.id"
-          :items="liveNote.items"
-          editable
+              v-else
+              :ref="(el) => setBlockEl(block.id, el)"
+              :value="block.text"
+              rows="1"
+              :placeholder="i === 0 ? bodyPlaceholder : ''"
+              class="w-full resize-none overflow-hidden bg-transparent text-sm leading-relaxed outline-none placeholder:text-neutral-400"
+              @input="onProseInput(i, $event)"
+              @keydown="onProseKeydown"
             />
+          </template>
+        </div>
+        <!-- No checklist component. The items are lines of the textarea above, which
+             is what lets a list sit between two paragraphs (M304). -->
 
         <div v-if="labelList.length" class="flex flex-wrap gap-1.5 pt-1">
           <span
             v-for="lb in labelList"
             :key="lb.id"
             class="inline-flex items-center gap-1 rounded-full px-2 py-0.5 text-xs"
-            :class="labelChip(lb.color)"
+            :class="labelChip(lb)"
           >
             {{ lb.via_tag ? "#" + lb.name : lb.name }}
             <button
@@ -598,7 +713,7 @@ function revPreview(rev: NoteRevision): string {
           </button>
           <input ref="fileInput" type="file" class="hidden" @change="onFileChange" />
           <button
-            v-if="richEnabled && !liveNote.trashed && !showChecklist"
+            v-if="!liveNote.trashed"
             type="button"
             class="icon-btn"
             title="Add a checklist"

frontend/src/notes/blocks.ts

@@ -0,0 +1,110 @@
+// The editor's shape for a note body: a list of blocks rather than one string.
+//
+// The note is still one markdown body underneath (M304) — this is a rendering and
+// input shape, and nothing below the editor can tell it exists. `joinBlocks` puts the
+// string back together on every edit, and for a body already in canonical form it
+// returns exactly what `splitBlocks` was handed.
+//
+// Why blocks at all: a checklist item has to be a real `<input type="checkbox">`, and
+// a widget cannot live inside a `<textarea>`. Only a `contenteditable` could hold one,
+// and that is a different editor with a different set of problems.
+//
+// A run of prose lines is ONE block, not one per line. Typing a paragraph has to feel
+// like typing a paragraph, and a separate field under every sentence would break the
+// caret mid-sentence. Only a checklist item earns a block, because only a checklist
+// item needs a widget.
+//
+// The mirror of android/.../ui/EditorBlock.kt, deliberately: the two editors should
+// behave the same, and the cheapest way to keep them that way is for the shapes to
+// read alike.
+
+import { parseTaskLine, renderTaskLine } from "./markdown";
+
+export interface EditorBlock {
+  /** Stable across edits, so Vue keeps a field's caret when a block is inserted above
+   *  it. Content cannot serve as the key — two empty items are identical and neither
+   *  is the other. */
+  id: number;
+  text: string;
+  /** null for prose; ticked-or-not for a checklist item. */
+  checked: boolean | null;
+}
+
+/** Split a body into blocks, numbering them from `firstId`. */
+export function splitBlocks(body: string, firstId = 0): EditorBlock[] {
+  const out: EditorBlock[] = [];
+  const prose: string[] = [];
+  let id = firstId;
+
+  const flushProse = () => {
+    if (prose.length) {
+      out.push({ id: id++, text: prose.join("\n"), checked: null });
+      prose.length = 0;
+    }
+  };
+
+  for (const line of (body ?? "").split("\n")) {
+    const task = parseTaskLine(line);
+    if (task) {
+      flushProse();
+      out.push({ id: id++, text: task.text, checked: task.checked });
+    } else {
+      prose.push(line);
+    }
+  }
+  flushProse();
+
+  // Never empty: an empty note still needs one field to type into.
+  return out.length ? out : [{ id, text: "", checked: null }];
+}
+
+/** The body those blocks stand for. */
+export function joinBlocks(blocks: EditorBlock[]): string {
+  return blocks.map((b) => (b.checked === null ? b.text : renderTaskLine(b.text, b.checked))).join("\n");
+}
+
+/** An id nothing else is using. Monotonic within a session, which is all it has to be. */
+export function nextId(blocks: EditorBlock[]): number {
+  return blocks.reduce((max, b) => Math.max(max, b.id), -1) + 1;
+}
+
+/**
+ * What Enter does on a checklist item, and which block should hold the caret after.
+ *
+ * On an item with words in it, a new empty item below. On an EMPTY one, the item
+ * becomes prose — which is how a list ENDS, and the only way to get a paragraph after
+ * one. Without that half a list is impossible to get out of.
+ *
+ * Appends rather than splitting at the caret: splitting an item in two is a rarity,
+ * and the caret is at the end for every ordinary use of that key.
+ */
+export function afterEnter(blocks: EditorBlock[], index: number): { blocks: EditorBlock[]; focus: number } {
+  const block = blocks[index];
+  const out = [...blocks];
+  if (!block.text.trim()) {
+    out[index] = { ...block, text: "", checked: null };
+    return { blocks: out, focus: block.id };
+  }
+  const id = nextId(blocks);
+  out.splice(index + 1, 0, { id, text: "", checked: false });
+  return { blocks: out, focus: id };
+}
+
+/**
+ * Drop a block, leaving at least one field to type into.
+ *
+ * Focus goes to the block above — or, when the first one was removed, to whichever
+ * takes its place. `index - 1` alone is -1 there, which would leave nothing focused.
+ */
+export function withoutIndex(blocks: EditorBlock[], index: number): { blocks: EditorBlock[]; focus: number | null } {
+  const kept = blocks.filter((_, i) => i !== index);
+  const fallback: EditorBlock[] = [{ id: nextId(blocks), text: "", checked: null }];
+  const remaining = kept.length ? kept : fallback;
+  return { blocks: remaining, focus: remaining[Math.max(0, index - 1)]?.id ?? null };
+}
+
+/** One more empty checklist item at the end, and the id to put the caret in. */
+export function plusTask(blocks: EditorBlock[]): { blocks: EditorBlock[]; focus: number } {
+  const id = nextId(blocks);
+  return { blocks: [...blocks, { id, text: "", checked: false }], focus: id };
+}

frontend/src/notes/colors.ts

@@ -17,18 +17,10 @@ export const NOTE_COLOR_KEYS = [
 
 export type NoteColor = (typeof NOTE_COLOR_KEYS)[number];
 
-export const NOTE_CARD_CLASSES: Record<NoteColor, string> = {
-  default: "bg-white border-neutral-200 dark:bg-neutral-900 dark:border-neutral-700",
-  red: "bg-red-50 border-red-200 dark:bg-red-950/40 dark:border-red-900",
-  orange: "bg-orange-50 border-orange-200 dark:bg-orange-950/40 dark:border-orange-900",
-  yellow: "bg-amber-50 border-amber-200 dark:bg-amber-950/40 dark:border-amber-900",
-  green: "bg-green-50 border-green-200 dark:bg-green-950/40 dark:border-green-900",
-  teal: "bg-teal-50 border-teal-200 dark:bg-teal-950/40 dark:border-teal-900",
-  blue: "bg-blue-50 border-blue-200 dark:bg-blue-950/40 dark:border-blue-900",
-  purple: "bg-purple-50 border-purple-200 dark:bg-purple-950/40 dark:border-purple-900",
-  pink: "bg-pink-50 border-pink-200 dark:bg-pink-950/40 dark:border-pink-900",
-  gray: "bg-neutral-100 border-neutral-300 dark:bg-neutral-800 dark:border-neutral-700",
-};
+/** Membership test for a colour key arriving from the server, which may be newer
+ *  than this client. Was a lookup in the subdued card table until that table was
+ *  deleted — an untagged note's fill is generated now, not chosen from a palette. */
+const KNOWN_COLORS = new Set<string>(NOTE_COLOR_KEYS);
 
 export const NOTE_SWATCH_CLASSES: Record<NoteColor, string> = {
   default: "bg-white dark:bg-neutral-600",
@@ -43,18 +35,26 @@ export const NOTE_SWATCH_CLASSES: Record<NoteColor, string> = {
   gray: "bg-neutral-400 dark:bg-neutral-500",
 };
 
-// Label chip tints (bg + readable text), keyed by the same color vocabulary.
+// Label chip tints (bg + readable text + a hairline edge), keyed by the same color
+// vocabulary.
+//
+// The RING is not decoration. A tagged note takes its first tag's colour and is drawn
+// at that hue's `-100` — exactly what the chip uses as its fill — so in light mode the
+// chip measured a contrast ratio of 1.00 against the card it had itself coloured.
+// Perfectly invisible; the tag name read as loose text. An edge holds the pill's shape
+// against ANY background, where shifting the fill only moves which card it collides
+// with.
 export const LABEL_CHIP_CLASSES: Record<NoteColor, string> = {
-  default: "bg-black/5 text-neutral-600 dark:bg-white/10 dark:text-neutral-300",
-  red: "bg-red-100 text-red-700 dark:bg-red-950/50 dark:text-red-300",
-  orange: "bg-orange-100 text-orange-700 dark:bg-orange-950/50 dark:text-orange-300",
-  yellow: "bg-amber-100 text-amber-800 dark:bg-amber-950/50 dark:text-amber-300",
-  green: "bg-green-100 text-green-700 dark:bg-green-950/50 dark:text-green-300",
-  teal: "bg-teal-100 text-teal-700 dark:bg-teal-950/50 dark:text-teal-300",
-  blue: "bg-blue-100 text-blue-700 dark:bg-blue-950/50 dark:text-blue-300",
-  purple: "bg-purple-100 text-purple-700 dark:bg-purple-950/50 dark:text-purple-300",
-  pink: "bg-pink-100 text-pink-700 dark:bg-pink-950/50 dark:text-pink-300",
-  gray: "bg-neutral-200 text-neutral-700 dark:bg-neutral-700 dark:text-neutral-200",
+  default: "bg-black/5 text-neutral-600 dark:bg-white/10 dark:text-neutral-300 ring-1 ring-inset ring-black/10 dark:ring-white/15",
+  red: "bg-red-100 text-red-700 dark:bg-red-950/50 dark:text-red-300 ring-1 ring-inset ring-red-700/60 dark:ring-red-300/60",
+  orange: "bg-orange-100 text-orange-700 dark:bg-orange-950/50 dark:text-orange-300 ring-1 ring-inset ring-orange-700/60 dark:ring-orange-300/60",
+  yellow: "bg-amber-100 text-amber-800 dark:bg-amber-950/50 dark:text-amber-300 ring-1 ring-inset ring-amber-700/60 dark:ring-amber-300/60",
+  green: "bg-green-100 text-green-700 dark:bg-green-950/50 dark:text-green-300 ring-1 ring-inset ring-green-700/60 dark:ring-green-300/60",
+  teal: "bg-teal-100 text-teal-700 dark:bg-teal-950/50 dark:text-teal-300 ring-1 ring-inset ring-teal-700/60 dark:ring-teal-300/60",
+  blue: "bg-blue-100 text-blue-700 dark:bg-blue-950/50 dark:text-blue-300 ring-1 ring-inset ring-blue-700/60 dark:ring-blue-300/60",
+  purple: "bg-purple-100 text-purple-700 dark:bg-purple-950/50 dark:text-purple-300 ring-1 ring-inset ring-purple-700/60 dark:ring-purple-300/60",
+  pink: "bg-pink-100 text-pink-700 dark:bg-pink-950/50 dark:text-pink-300 ring-1 ring-inset ring-pink-700/60 dark:ring-pink-300/60",
+  gray: "bg-neutral-200 text-neutral-700 dark:bg-neutral-700 dark:text-neutral-200 ring-1 ring-inset ring-neutral-700/60 dark:ring-neutral-200/60",
 };
 
 // Solid fills for graph nodes (SVG needs concrete colors, not Tailwind bg classes).
@@ -84,3 +84,311 @@ export const NOTE_COLOR_LABELS: Record<NoteColor, string> = {
   pink: "Pink",
   gray: "Gray",
 };
+
+// ---------------------------------------------------------------------------
+// Derived tints — the colour a note has when nothing chose one for it.
+//
+// A board of `default` notes is a wall of white rectangles and the eye gets no
+// help telling one from the next. Every note now carries some tint; this is where
+// an untagged one gets it.
+//
+// "RANDOM" MEANS DERIVED. The operator asked for "random subdued colors", but a
+// tint rolled at render time would differ between the phone and the browser and
+// change on every reload. Hashing the note's id is deterministic, identical on
+// every surface, costs no column and no migration, and a note keeps its colour
+// for life — which is what "random" actually meant here.
+//
+// THIS IS HALF A MIRRORED PAIR. `android/.../ui/NoteTint.kt` computes the same
+// hash over the same key order, and the two must agree exactly or a note is one
+// colour on the phone and another in the browser. Same discipline as the
+// checklist grammar's three implementations, and the same reason: a value that
+// disagrees across surfaces is a bug you cannot unsee and cannot explain.
+//
+// The Kotlin side has a unit test pinning the fixture below. THIS SIDE HAS NO
+// MECHANICAL GUARD — the frontend has no test runner, only `vue-tsc --noEmit`.
+// If you change anything here, check it against the fixture by hand.
+
+/** The tints a derived colour can land on: the palette minus `default`, which is
+ *  the white this exists to eliminate. `gray` stays — `bg-neutral-100` reads as a
+ *  deliberate card against the board's `bg-neutral-50`, not as an absence. */
+export const DERIVED_TINT_KEYS: readonly NoteColor[] = NOTE_COLOR_KEYS.filter(
+  (key) => key !== "default",
+);
+
+/**
+ * FNV-1a over the id's bytes, 32-bit.
+ *
+ * Chosen because both languages compute it identically in ten lines with no
+ * library. Explicitly NOT `String.hashCode()`: Kotlin's is specified but JS has
+ * no equivalent, and reimplementing Java's from memory in TypeScript is exactly
+ * how a mirror drifts.
+ *
+ * `& 0xff` is a no-op for the ASCII of a UUID, and is kept because it states the
+ * intent — this hashes BYTES, so the Kotlin side reading `id[i].code and 0xFF`
+ * is the same function rather than a coincidence.
+ */
+export function tintHash(id: string): number {
+  let hash = 0x811c9dc5;
+  for (let i = 0; i < id.length; i++) {
+    hash ^= id.charCodeAt(i) & 0xff;
+    // Math.imul, not `*`: JS numbers are doubles and a 32-bit overflow would be
+    // silently kept as precision instead of wrapping the way Kotlin's Int does.
+    hash = Math.imul(hash, 0x01000193) >>> 0;
+  }
+  return hash >>> 0;
+}
+
+/** The tint a note with no colour of its own wears. Stable for the life of the note. */
+export function derivedTint(id: string): NoteColor {
+  return DERIVED_TINT_KEYS[tintHash(id) % DERIVED_TINT_KEYS.length];
+}
+
+// ---------------------------------------------------------------------------
+// The fill for an UNTAGGED note, which is a different job from the palette above.
+//
+// The palette has nine keys and they MEAN something: a tag's colour. An untagged
+// note's fill means nothing at all — it exists so a board is not a monolithic wall.
+// Tying the second job to the first was the mistake. Nine keys is far too few for a
+// board of any size, and once the nine were subdued enough not to shout they became
+// indistinguishable from each other: measured, the nine dark fills were separated by
+// at most a 1.03 contrast ratio, which is to say not at all. Nine tints that look
+// like three is exactly the wall the tint was added to break up.
+//
+// So this hashes to a colour directly rather than to a key. 338 distinct fills in
+// dark, 193 in light, against nine.
+//
+// TWO AXES, AND THE SECOND ONE IS THE FIX. The old ramp varied hue while pinning
+// every fill to the same lightness — deliberately, so each would read as a card
+// against the board. But the eye separates by lightness first, so nine hues at one
+// lightness read as one card repeated. Varying lightness too is what makes the
+// difference; hue alone never could at this darkness.
+//
+// It is only SAFE to vary lightness because the card now has a grey edge of its own
+// (NoteCard.vue). While the fill was the only boundary the card had, it could not
+// afford to drift toward the board. The edge bought that freedom.
+//
+// MIRRORED in `android/.../ui/DerivedTint.kt`, which has the unit test. Same hash,
+// same levels, same rounding — see the fixture below.
+
+/** Lightness steps a generated fill can land on. Six rather than three because the
+ *  levels are what carry the variety, and rather than twelve because past a point
+ *  they stop being distinguishable and only cost contrast headroom. */
+const TINT_LEVELS = 6;
+
+// Saturation is FIXED, and that is what keeps this subtle whichever hue it lands on.
+// Variety comes from hue and lightness; loudness would come from saturation, so
+// saturation is the one dial the hash never touches.
+const DARK_SATURATION = 0.25;
+const LIGHT_SATURATION = 0.6;
+
+// HSL LIGHTNESS IS NOT LUMINANCE, and the dark floor is set by the difference.
+//
+// The obvious floor is `neutral-900`'s own lightness, 0.090 — start at the plain card
+// surface and climb, so no note ever recedes into the board. That was the first
+// attempt and it was wrong: at a FIXED HSL lightness the eye sees wildly different
+// brightnesses by hue, because green carries 71% of the luminance formula and blue
+// only 7%. At L=0.090 a yellow measures 0.0118 and a blue 0.0061 — the blue landing
+// 1.41x DARKER than the card it was meant to match, so a sixth of the board would
+// have been holes rather than variety.
+//
+// 0.113 is the lowest floor at which every hue clears the card surface, solved for
+// rather than guessed: 1.11-1.71 against the board, where the old single level
+// managed 1.14. Light runs the other way, from white down past the `neutral-50`
+// board; a card slightly darker than the board still reads as one because the edge
+// says so, and near white the hue barely moves luminance at all so it needs no
+// equivalent correction.
+const DARK_LIGHTNESS = [0.113, 0.127, 0.141, 0.155, 0.169, 0.183];
+const LIGHT_LIGHTNESS = [1.0, 0.99, 0.98, 0.97, 0.96, 0.95];
+
+/**
+ * The opaque fill an untagged note wears, as `#rrggbb`. Stable for the note's life.
+ *
+ * Hue and level are read from DIFFERENT parts of the hash so a note's shade is not a
+ * function of its hue — two notes of nearly the same hue should still be able to
+ * differ in weight, which is half of where the variety comes from.
+ */
+export function derivedFill(id: string, dark: boolean): string {
+  const hash = tintHash(id);
+  const level = (hash >>> 16) % TINT_LEVELS;
+  return hslHex(
+    hash % 360,
+    dark ? DARK_SATURATION : LIGHT_SATURATION,
+    dark ? DARK_LIGHTNESS[level] : LIGHT_LIGHTNESS[level],
+  );
+}
+
+/**
+ * Textbook HSL to RGB, written out rather than pulled from a library because the
+ * Kotlin side has to compute the same bytes and there is no library both can share.
+ * Rounding is `floor(v + 0.5)` on both sides rather than the language's `round`:
+ * Kotlin rounds half away from zero and JS rounds half up, which agree here, but
+ * stating the rule leaves nothing for a future reader to have to check.
+ */
+function hslHex(hue: number, saturation: number, lightness: number): string {
+  const chroma = (1 - Math.abs(2 * lightness - 1)) * saturation;
+  const sector = hue / 60;
+  const second = chroma * (1 - Math.abs((sector % 2) - 1));
+  const match = lightness - chroma / 2;
+  const ramps: [number, number, number][] = [
+    [chroma, second, 0],
+    [second, chroma, 0],
+    [0, chroma, second],
+    [0, second, chroma],
+    [second, 0, chroma],
+    [chroma, 0, second],
+  ];
+  const [red, green, blue] = ramps[Math.floor(sector)];
+  const byte = (v: number) =>
+    Math.min(255, Math.max(0, Math.floor((v + match) * 255 + 0.5)))
+      .toString(16)
+      .padStart(2, "0");
+  return `#${byte(red)}${byte(green)}${byte(blue)}`;
+}
+
+/**
+ * The colour to paint a LABEL — its chip, and (step 3) every note carrying it.
+ *
+ * Derived from the tag's NAME, not stored, when nobody has picked one. Every `#tag`
+ * ever typed is currently `default`: `notes/tags.py` mints one as
+ * `Label(owner_id=…, name=name)` with no colour, so it takes the column default.
+ * Tag-driven note colour against that would leave the board exactly as grey as it
+ * was.
+ *
+ * DERIVED RATHER THAN PERSISTED AT MINT TIME, reversing the original plan in #2965.
+ * That plan wanted a hashed colour written at each of the four places a label can be
+ * born — and named the risk itself: `find_or_create_label` is "easy to miss, and it
+ * is the common one", because most tags are born from typing `#grocery`, not from a
+ * management screen. Deriving has no mint points to miss, needs no backfill for the
+ * tags that already exist, and reuses the hash the notes already use. The cost is
+ * that renaming a tag recolours it, which is defensible: the name IS the tag.
+ *
+ * An explicitly-picked colour is still stored and still wins, so tag colours stay
+ * editable exactly as asked.
+ *
+ * Lowercased because tags dedupe case-insensitively — `#Todo` renamed to `#todo` is
+ * the same tag and should not change colour. Both `toLowerCase` here and Kotlin's
+ * `lowercase()` are locale-independent, so the mirror holds.
+ */
+export function resolveLabelColor(label: { name: string; color?: string | null }): NoteColor {
+  const picked = label.color as NoteColor | undefined | null;
+  if (picked && picked !== "default" && KNOWN_COLORS.has(picked)) return picked;
+  if (!label.name) return "default";
+  return derivedTint(label.name.toLowerCase());
+}
+
+// Fixture — the same ids and expected keys the Kotlin test asserts. Kept here as
+// prose because there is nowhere on this side to assert it. If you change the hash
+// or the key order, these four must still hold on BOTH surfaces:
+//
+//   00000000-0000-0000-0000-000000000000  0xbe478ed1  purple
+//   11111111-1111-1111-1111-111111111111  0x3d75cc01  blue
+//   6ba7b810-9dad-11d1-80b4-00c04fd430c8  0xf108e530  orange
+//   f47ac10b-58cc-4372-a567-0e02b2c3d479  0x5b651540  orange
+//
+// And for labels, which hash the lowercased NAME rather than an id:
+//
+//   todo -> pink     grocery -> blue    work -> green    home -> gray
+//   ideas -> green   reading -> gray    urgent -> red
+//
+// And for derivedFill, which uses the same hash on two axes (dark / light):
+//
+//   00000000-0000-0000-0000-000000000000  hue 177 lev 3  #1e3130  #f3fcfb
+//   11111111-1111-1111-1111-111111111111  hue 113 lev 1  #1a2818  #fbfefb
+//   6ba7b810-9dad-11d1-80b4-00c04fd430c8  hue 136 lev 0  #162419  #ffffff
+//   f47ac10b-58cc-4372-a567-0e02b2c3d479  hue 352 lev 3  #311e20  #fcf3f4
+//
+// Note `work`/`ideas` and `home`/`reading` collide. Nine keys makes that unavoidable
+// and it is not a bug: colour hints that two notes are related, it never claims they
+// carry the same tag. The chip's text is what says which tag it is.
+
+// The FULL-strength ramp: what a note wears when its colour was CHOSEN — by a tag, or
+// (until step 5) by the picker. One Tailwind step deeper in light mode, and a much
+// heavier fill in dark.
+//
+// UNCHANGED by the border pass, deliberately. The operator's complaint was the edge
+// line and the loudness of the DERIVED tint; the chosen colours were "pretty well"
+// where they landed, and a ramp somebody has already signed off on is not something
+// to redo while fixing something else.
+//
+// THERE IS NO SECOND RAMP ANY MORE. This one is reached only by a note that HAS a
+// colour; a note without one gets a generated fill instead (`derivedFill`), because
+// nine palette keys could never carry both jobs. The palette says WHICH TAG. The
+// generator says nothing at all, and only has to keep the board from repeating.
+//
+// So these values do not need to be subtle and never did — a tagged note is making a
+// statement, and the quiet end of the board is now handled somewhere else entirely.
+export const NOTE_CARD_CLASSES_STRONG: Record<NoteColor, string> = {
+  default: "bg-white dark:bg-neutral-900",
+  red: "bg-red-100 dark:bg-red-950/70",
+  orange: "bg-orange-100 dark:bg-orange-950/70",
+  yellow: "bg-amber-100 dark:bg-amber-950/70",
+  green: "bg-green-100 dark:bg-green-950/70",
+  teal: "bg-teal-100 dark:bg-teal-950/70",
+  blue: "bg-blue-100 dark:bg-blue-950/70",
+  purple: "bg-purple-100 dark:bg-purple-950/70",
+  pink: "bg-pink-100 dark:bg-pink-950/70",
+  gray: "bg-neutral-200 dark:bg-neutral-800/70",
+};
+
+/**
+ * The palette key a note was GIVEN, or null when nothing gave it one.
+ *
+ * Null is the interesting answer: it means the fill has to be generated, because the
+ * note carries no statement about what it is. Everything downstream branches here.
+ *
+ * Resolution order, and why: an explicit pick beats a tag because it is the more
+ * specific statement and the picker still exists. The FIRST label wins among tags —
+ * it is the one the person controls by typing, where alphabetical or most-used would
+ * move a note's colour when an unrelated tag was added somewhere else.
+ *
+ * Manual labels count the same as `#tags`. Someone looking at a chip cannot tell which
+ * kind they made, and two identically-tagged notes in different colours for an
+ * invisible reason is worse than the rule being slightly loose.
+ */
+export function chosenNoteColor(note: {
+  color?: string | null;
+  labels?: { name: string; color: string }[];
+}): NoteColor | null {
+  const picked = note.color as NoteColor | undefined | null;
+  if (picked && picked !== "default" && KNOWN_COLORS.has(picked)) return picked;
+  const first = note.labels?.[0];
+  if (first) return resolveLabelColor(first);
+  return null;
+}
+
+/**
+ * The class list for a note card.
+ *
+ * A tagged note gets a palette class. An untagged one gets `note-tint`, whose fill
+ * arrives through the custom properties in `noteTintVars` — see the rule in
+ * style.css, which exists because an inline style cannot answer a media query and the
+ * light and dark fills are two different generated colours.
+ */
+export function noteCardClasses(note: {
+  id: string;
+  color?: string | null;
+  labels?: { name: string; color: string }[];
+}): string {
+  const chosen = chosenNoteColor(note);
+  return chosen ? NOTE_CARD_CLASSES_STRONG[chosen] : "note-tint";
+}
+
+/**
+ * The generated fill for an untagged note, as the two custom properties `note-tint`
+ * reads — or undefined when the note has a colour of its own, or is a draft.
+ *
+ * A draft carries no id, so there is nothing to derive from; `note-tint`'s fallbacks
+ * catch that and paint the plain card surface. Hashing the empty string instead would
+ * give every draft the same fill and then change it at save time anyway.
+ */
+export function noteTintVars(note: {
+  id: string;
+  color?: string | null;
+  labels?: { name: string; color: string }[];
+}): Record<string, string> | undefined {
+  if (chosenNoteColor(note) || !note.id) return undefined;
+  return {
+    "--tint-light": derivedFill(note.id, false),
+    "--tint-dark": derivedFill(note.id, true),
+  };
+}

frontend/src/notes/markdown.ts

@@ -13,10 +13,22 @@ export interface InlineToken {
 
 // Flat (non-discriminated) shape on purpose — keeps template type-checking simple.
 export interface Block {
-  type: "p" | "h1" | "h2" | "h3" | "quote" | "ul" | "ol" | "pre";
+  type: "p" | "h1" | "h2" | "h3" | "quote" | "ul" | "ol" | "pre" | "task";
   inline?: InlineToken[];
   items?: InlineToken[][];
   value?: string;
+  /** `task` only: one entry per `items` entry, parallel by position. */
+  tasks?: TaskMeta[];
+}
+
+export interface TaskMeta {
+  /** This item's ordinal among ALL task lines in the body, in document order.
+   *  That is the id the server and the native clients address an item by, so a
+   *  checkbox can be toggled straight from it. Counted across blocks, not within
+   *  one, and unaffected by the card truncating the body — the card only ever
+   *  drops lines from the END. */
+  index: number;
+  checked: boolean;
 }
 
 // Order matters: code is matched before emphasis so its contents aren't re-parsed;
@@ -44,11 +56,45 @@ export function parseInline(text: string): InlineToken[] {
   return tokens;
 }
 
+// A checklist item: the third implementation of one grammar, alongside
+// core/src/local/derive.rs and src/thoughtsync/notes/checklist.py. A difference
+// between any two of them is a checklist that changes shape when it syncs (M304).
+//
+// `-` and `*` only, deliberately, even though the `ul` matcher below also takes `+`.
+// The other two implementations do not take `+`, and one grammar in three places has
+// to be one grammar; a `+ [ ] x` line renders as an ordinary bullet everywhere,
+// which is at least consistent.
+const TASK_RE = /^\s*[-*] +\[([ xX])\](?: +(.*))?$/;
+
+export interface TaskLine {
+  checked: boolean;
+  text: string;
+}
+
+/** One task line's parts, or null when the line is prose.
+ *
+ *  Exported so the EDITOR's block split (notes/blocks.ts) and this read-view parser
+ *  agree by construction rather than by comment. One grammar, one matcher. */
+export function parseTaskLine(line: string): TaskLine | null {
+  const m = TASK_RE.exec(line);
+  return m ? { checked: m[1] !== " ", text: m[2] ?? "" } : null;
+}
+
+/** One item as the body line that stores it, in canonical form — `- [x] `, lowercase,
+ *  and no trailing space when the item is empty so a round trip does not grow it. */
+export function renderTaskLine(text: string, checked: boolean): string {
+  const mark = checked ? "x" : " ";
+  return text ? `- [${mark}] ${text}` : `- [${mark}]`;
+}
+
 export function parseMarkdown(text: string): Block[] {
   const lines = (text ?? "").split("\n");
   const blocks: Block[] = [];
   let paragraph: string[] = [];
   let i = 0;
+  // Runs across the whole document, not per block, because that is what the item's
+  // id means everywhere else.
+  let taskIndex = 0;
 
   const flushPara = () => {
     if (paragraph.length) {
@@ -96,6 +142,25 @@ export function parseMarkdown(text: string): Block[] {
       continue;
     }
 
+    // Task list, BEFORE the plain bullet below — which would otherwise swallow
+    // `- [ ] x` as an ordinary list item and leave the brackets showing. Same
+    // ordering reason as `code` being matched before emphasis in INLINE_RE.
+    if (parseTaskLine(line)) {
+      flushPara();
+      const items: InlineToken[][] = [];
+      const tasks: TaskMeta[] = [];
+      while (i < lines.length) {
+        const task = parseTaskLine(lines[i]);
+        if (!task) break;
+        items.push(parseInline(task.text));
+        tasks.push({ index: taskIndex, checked: task.checked });
+        taskIndex++;
+        i++;
+      }
+      blocks.push({ type: "task", items, tasks });
+      continue;
+    }
+
     // Unordered list: -, *, or + then a space.
     if (/^\s*[-*+]\s+/.test(line)) {
       flushPara();

frontend/src/style.css

@@ -47,6 +47,26 @@ body {
   }
 }
 
+/* An untagged note's fill is GENERATED from its id, not chosen from the palette —
+ * see `derivedFill` in notes/colors.ts for why nine keys was never going to be
+ * enough. That means it cannot be a Tailwind class, and it cannot be a plain inline
+ * style either: light and dark are two different computed colours and an inline
+ * style has no way to answer a media query. So the card publishes both as custom
+ * properties and this rule picks between them.
+ *
+ * The fallbacks are the draft case. A note with no id yet has nothing to hash, so it
+ * publishes no properties and lands on the plain card surface — one colour change at
+ * save time, rather than every draft sharing a fill and then changing anyway. */
+.note-tint {
+  background-color: var(--tint-light, #ffffff);
+}
+
+@media (prefers-color-scheme: dark) {
+  .note-tint {
+    background-color: var(--tint-dark, #171717);
+  }
+}
+
 /* Motion is a feature, not a given. Anyone whose OS says "reduce motion" has told
  * us something about vestibular comfort or attention, and the answer is to arrive
  * instantly rather than to animate faster.

src/thoughtsync/models/all.py

@@ -9,7 +9,6 @@ from . import (  # noqa: F401
     label,
     note,
     note_attachment,
-    note_item,
     note_link_preview,
     note_revision,
     saved_filter,

src/thoughtsync/models/note.py

@@ -46,7 +46,6 @@ class Note(Base):
     display_title: Mapped[str] = mapped_column(Text(), nullable=False, server_default="")
     body: Mapped[str] = mapped_column(Text(), nullable=False, server_default="")
     color: Mapped[str] = mapped_column(Text(), nullable=False, server_default="default")
-    # 'text' (freeform body) or 'list' (a checklist of note_items).
     # Manual drag order (higher = earlier); 0 until the user reorders.
     position: Mapped[int] = mapped_column(Integer(), nullable=False, server_default="0")
     pinned: Mapped[bool] = mapped_column(Boolean(), nullable=False, server_default=func.false())

src/thoughtsync/models/note_item.py

@@ -1,29 +0,0 @@
-from __future__ import annotations
-
-import uuid
-from datetime import datetime
-
-from sqlalchemy import Boolean, DateTime, ForeignKey, Integer, Text, func
-from sqlalchemy.dialects.postgresql import UUID
-from sqlalchemy.orm import Mapped, mapped_column
-
-from . import Base
-
-
-class NoteItem(Base):
-    """A single checklist item on a note.
-
-    Any note can have them. There is no note "kind" gating this — a checklist is
-    something a note HAS, not something a note IS (M13 step 2).
-    """
-
-    __tablename__ = "note_items"
-
-    id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
-    note_id: Mapped[uuid.UUID] = mapped_column(
-        UUID(as_uuid=True), ForeignKey("notes.id", ondelete="CASCADE"), nullable=False
-    )
-    text: Mapped[str] = mapped_column(Text(), nullable=False)
-    checked: Mapped[bool] = mapped_column(Boolean(), nullable=False, server_default=func.false())
-    position: Mapped[int] = mapped_column(Integer(), nullable=False, server_default="0")
-    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, server_default=func.now())

src/thoughtsync/notes/__init__.py

@@ -31,9 +31,16 @@ from ..labeling import reconcile_manual_labels, resolve_owned_label_ids
 from ..models.label import Label, NoteLabel
 from ..models.note import Note
 from ..models.note_attachment import NoteAttachment
-from ..models.note_item import NoteItem
 from ..models.note_link_preview import NoteLinkPreview
 from ..models.note_revision import NoteRevision
+from ..revisions import should_snapshot
+from .checklist import (
+    append_item,
+    parse_items,
+    remove_item,
+    set_item_checked,
+    set_item_text,
+)
 from ..responses import json_error, not_found, parse_uuid
 from ..retention import purge_note
 from ..settings import get_setting
@@ -69,7 +76,7 @@ from .tags import (
     parse_tags,
 )
 from .recurrence import REMINDER_RECURRENCES, next_occurrence, normalize_recurrence
-from .serialize import _items_for_notes, _labels_for_notes, _serialize_note, _serialize_notes
+from .serialize import _labels_for_notes, _serialize_note, _serialize_notes
 
 __all__ = [
     "bp",
@@ -224,7 +231,6 @@ async def export_notes():
         ).all()
         ids = [n.id for n in notes_list]
         labels_map = await _labels_for_notes(db, ids)
-        items_map = await _items_for_notes(db, ids)
         att_rows = (
             (await db.scalars(select(NoteAttachment).where(NoteAttachment.note_id.in_(ids)))).all() if ids else []
         )
@@ -246,7 +252,6 @@ async def export_notes():
         with zipfile.ZipFile(buf, "w", zipfile.ZIP_DEFLATED) as zf:
             for n in notes_list:
                 labels = labels_map.get(n.id, [])
-                items = items_map.get(n.id, [])
                 atts = att_by_note.get(n.id, [])
                 short = str(n.id)[:8]
                 payload["notes"].append(
@@ -262,13 +267,12 @@ async def export_notes():
                         "created_at": n.created_at.isoformat() if n.created_at else None,
                         "updated_at": n.updated_at.isoformat() if n.updated_at else None,
                         "labels": [lb["name"] for lb in labels],
-                        "items": [{"text": it["text"], "checked": it["checked"]} for it in items],
                         "attachments": [
                             {"file": f"attachments/{short}/{os.path.basename(a.path)}", "mime": a.mime} for a in atts
                         ],
                     }
                 )
-                zf.writestr(f"notes/{_slugify(n.display_title)}-{short}.md", _note_markdown(n, labels, items))
+                zf.writestr(f"notes/{_slugify(n.display_title)}-{short}.md", _note_markdown(n, labels))
                 for a in atts:
                     src = Config.media_root() / a.path
                     if src.is_file():
@@ -384,24 +388,6 @@ async def reorder_notes():
         return jsonify({"ok": True})
 
 
-async def _name_for(db, note: Note, item_texts: list[str] | None = None) -> str:
-    """The note's display name, consulting its checklist only when the body is silent.
-
-    `item_texts` short-circuits the query for callers that already hold the items
-    (create, import). Everyone else pays one narrow SELECT, and only when the body
-    produced nothing — which is the uncommon case.
-    """
-    name = derive_display_title(note.body)
-    if name:
-        return name
-    if item_texts is not None:
-        return derive_display_title("", item_texts[0] if item_texts else None)
-    first = await db.scalar(
-        select(NoteItem.text).where(NoteItem.note_id == note.id).order_by(NoteItem.position).limit(1)
-    )
-    return derive_display_title("", first)
-
-
 @bp.post("")
 @login_required
 async def create_note():
@@ -418,17 +404,20 @@ async def create_note():
                 Note.owner_id == g.user_id, Note.deleted_at.is_(None)
             )
         )
+        # Items still arrive separately — a client holds a list, not a blob — but they
+        # are folded into the body, which is where a checklist lives now (M304).
+        for text in item_texts:
+            body = append_item(body, text)
         note = Note(
             owner_id=g.user_id,
-            display_title=derive_display_title(body, item_texts[0] if item_texts else None),
+            display_title=derive_display_title(body),
             body=body,
             color=normalize_color(data.get("color")),
             position=int(max_pos) + 1,
         )
         db.add(note)
-        await db.flush()  # assign note.id before writing items/links
-        for pos, text in enumerate(item_texts):
-            db.add(NoteItem(note_id=note.id, text=text, position=pos))
+        await db.flush()  # assign note.id before writing links
+        # The FOLDED body: an item can carry a #tag too.
         await _reconcile_tags(db, note)
         await db.commit()
         await db.refresh(note)
@@ -483,10 +472,12 @@ async def update_note(note_id: str):
         if "recurrence" in data:
             note.recurrence = normalize_recurrence(data["recurrence"])
         if "body" in data:
-            note.display_title = await _name_for(db, note)
+            note.display_title = derive_display_title(note.body)
             await _reconcile_tags(db, note)
-        # Version history: snapshot the PRE-edit body whenever it changed.
-        if note.body != old_body:
+        # Version history: snapshot the PRE-edit body, once per editing session
+        # rather than once per write — see revisions.should_snapshot. Writing often
+        # is what lets a client autosave instead of hoarding text until it closes.
+        if await should_snapshot(db, note.id, old_body, note.body):
             db.add(NoteRevision(note_id=note.id, body=old_body))
         await db.commit()
         await db.refresh(note)
@@ -540,7 +531,7 @@ async def restore_revision(note_id: str, rev_id: str):
         # the revision — with the same body ripple as a normal edit.
         db.add(NoteRevision(note_id=note.id, body=note.body))
         note.body = rev.body
-        note.display_title = await _name_for(db, note)
+        note.display_title = derive_display_title(note.body)
         await _reconcile_tags(db, note)
         await db.commit()
         await db.refresh(note)
@@ -572,11 +563,35 @@ async def set_note_labels(note_id: str):
         return jsonify(await _serialize_note(db, note))
 
 
-async def _get_item(db, note: Note, item_id: str) -> NoteItem | None:
-    iid = parse_uuid(item_id)
-    if iid is None:
+def _item_index(item_id: str) -> int | None:
+    """An item's id is its ordinal (see serialize.items_of). Anything else is a stale
+    id from a client that has not reloaded, and the answer to those is 404."""
+    try:
+        index = int(item_id)
+    except (TypeError, ValueError):
         return None
-    return await db.scalar(select(NoteItem).where(NoteItem.id == iid, NoteItem.note_id == note.id))
+    return index if index >= 0 else None
+
+
+async def _rewrite_body(db, note: Note, body: str):
+    """Every item mutation is a body edit, so all of them land here.
+
+    One place means one place that snapshots a revision, re-derives `#tags`, recomputes
+    the name and queues link unfurls — rather than three routes each remembering to.
+    Deliberately the same sequence the PATCH route runs for a body change, because it
+    IS a body change.
+    """
+    old_body = note.body
+    if await should_snapshot(db, note.id, old_body, body):
+        db.add(NoteRevision(note_id=note.id, body=old_body))
+    note.body = body
+    note.display_title = derive_display_title(body)
+    await _reconcile_tags(db, note)
+    await db.commit()
+    await db.refresh(note)
+    if note.body != old_body:
+        schedule_unfurls(note.id, note.body)
+    return jsonify(await _serialize_note(db, note))
 
 
 @bp.post("/<note_id>/items")
@@ -588,70 +603,49 @@ async def add_item(note_id: str):
         note = await _get_owned(db, note_id)
         if note is None:
             return not_found()
-        max_pos = await db.scalar(
-            select(func.coalesce(func.max(NoteItem.position), -1)).where(NoteItem.note_id == note.id)
-        )
-        db.add(NoteItem(note_id=note.id, text=text, position=int(max_pos) + 1))
-        await db.commit()
-        return jsonify(await _serialize_note(db, note)), 201
+        response = await _rewrite_body(db, note, append_item(note.body, text))
+        return response, 201
 
 
 @bp.patch("/<note_id>/items/<item_id>")
 @login_required
 async def update_item(note_id: str, item_id: str):
     data = await request.get_json(silent=True) or {}
+    index = _item_index(item_id)
+    if index is None:
+        return not_found()
     async with session_scope() as db:
         note = await _get_owned(db, note_id)
         if note is None:
             return not_found()
-        item = await _get_item(db, note, item_id)
-        if item is None:
+        if index >= len(parse_items(note.body)):
             return not_found()
+        body = note.body
         if "text" in data and isinstance(data["text"], str):
-            item.text = data["text"]
+            body = set_item_text(body, index, data["text"])
         if "checked" in data:
-            item.checked = bool(data["checked"])
-        await db.commit()
-        return jsonify(await _serialize_note(db, note))
+            body = set_item_checked(body, index, bool(data["checked"]))
+        return await _rewrite_body(db, note, body)
 
 
 @bp.delete("/<note_id>/items/<item_id>")
 @login_required
 async def delete_item(note_id: str, item_id: str):
+    index = _item_index(item_id)
+    if index is None:
+        return not_found()
     async with session_scope() as db:
         note = await _get_owned(db, note_id)
         if note is None:
             return not_found()
-        item = await _get_item(db, note, item_id)
-        if item is None:
+        if index >= len(parse_items(note.body)):
             return not_found()
-        await db.delete(item)
-        await db.commit()
-        return jsonify(await _serialize_note(db, note))
+        return await _rewrite_body(db, note, remove_item(note.body, index))
 
 
-@bp.post("/<note_id>/items/reorder")
-@login_required
-async def reorder_items(note_id: str):
-    data = await request.get_json(silent=True) or {}
-    order = data.get("item_ids")
-    if not isinstance(order, list):
-        return json_error("item_ids must be a list", 400)
-    async with session_scope() as db:
-        note = await _get_owned(db, note_id)
-        if note is None:
-            return not_found()
-        existing = {
-            str(i.id): i for i in (await db.scalars(select(NoteItem).where(NoteItem.note_id == note.id))).all()
-        }
-        pos = 0
-        for iid in order:
-            item = existing.get(str(iid))
-            if item is not None:
-                item.position = pos
-                pos += 1
-        await db.commit()
-        return jsonify(await _serialize_note(db, note))
+# The reorder route is gone with M304. Reordering a checklist is moving a line, which
+# is something a text editor already does and no client ever called this for — the
+# only reference to it in the tree was a test asserting the route existed.
 
 
 @bp.post("/<note_id>/attachments")

src/thoughtsync/notes/checklist.py

@@ -0,0 +1,150 @@
+"""Checklist items — a note's body IS its checklist (M304).
+
+A `- [ ] milk` line is the item. There is no `note_items` table beside the body any
+more, which is what lets a list sit BETWEEN two paragraphs: rows had a position in a
+table and no position in the text, so a separate list could only ever render after
+the prose no matter how it was styled.
+
+The same shape as `tags.py`, one strength further along. Tags are derived from the
+body too, but they MATERIALISE into `note_labels` rows because the board queries by
+label. Items materialise into nothing, because nothing queries them — their only
+readers are the card, the editor and `display_title`. So `parse_items` is the whole
+storage layer for a checklist, and the rewriters below are how one is edited.
+
+THE GRAMMAR IS SHARED. Three implementations exist and they have to agree, because a
+difference between any two of them is a checklist that changes shape when it syncs:
+
+    core/src/local/derive.rs     the native clients (desktop + Android)
+    src/thoughtsync/notes/checklist.py   this file, the server
+    frontend/src/notes/markdown.ts       the browser
+
+    optional indent, `-` or `*`, one-or-more spaces, `[ ]`/`[x]`/`[X]`,
+    then either end-of-line or one-or-more spaces and the text.
+
+`*` is accepted because markdown.ts already takes it for a plain bullet, and a rule
+that allowed `* item` but not `* [ ] item` would be one nobody could guess. `- [ ]`
+with nothing after it IS an item with empty text — that is what pressing Enter on a
+list leaves behind, and refusing to parse it would make a half-typed list stop being
+a list. `- [X]` parses as checked and renders back lowercase, so one canonical form
+survives a round trip.
+"""
+from __future__ import annotations
+
+import re
+from dataclasses import dataclass
+
+# Anchored at both ends: a `[ ]` mid-sentence is prose, and `- [ ]x` (no space after
+# the brackets) is a sentence that happens to start with brackets, not a marker.
+_TASK_RE = re.compile(r"^(?P<indent>\s*)(?P<bullet>[-*]) +\[(?P<mark>[ xX])\](?: +(?P<text>.*))?$")
+
+
+@dataclass(frozen=True)
+class Item:
+    """One checklist item. Its position in the parsed list is its identity — the same
+    thing `position` meant when these were rows, and all the wire ever carried."""
+
+    text: str
+    checked: bool
+
+
+def parse_items(body: str | None) -> list[Item]:
+    """Every checklist item in `body`, in the order they appear."""
+    out: list[Item] = []
+    for line in (body or "").split("\n"):
+        match = _TASK_RE.match(line)
+        if match:
+            out.append(Item(text=match.group("text") or "", checked=match.group("mark") in "xX"))
+    return out
+
+
+def render_item(text: str, checked: bool, indent: str = "", bullet: str = "-") -> str:
+    """One item as the line that stores it.
+
+    Always lowercase `x`, whatever was parsed: one canonical output is what makes a
+    round trip stable, so `- [X]` normalises the first time it is touched and never
+    again.
+    """
+    mark = "x" if checked else " "
+    if not text:
+        return f"{indent}{bullet} [{mark}]"
+    return f"{indent}{bullet} [{mark}] {text}"
+
+
+def strip_marker(line: str) -> str:
+    """The text of a line with its task marker removed, or the line as it was.
+
+    For naming a note: a list-only note is named by its first item, and calling one
+    "- [ ] milk" would be showing someone the storage instead of the note.
+    """
+    match = _TASK_RE.match(line)
+    return (match.group("text") or "") if match else line
+
+
+def _rewrite(body: str, index: int, replace) -> str:
+    """Rewrite the `index`-th task line with `replace`, or drop it when `replace`
+    returns None.
+
+    A body with fewer task lines than that is returned UNCHANGED rather than raising:
+    the index comes from a client that may be a moment behind the server, and a stale
+    request should do nothing rather than 500.
+    """
+    lines = body.split("\n")
+    target = None
+    seen = 0
+    for n, line in enumerate(lines):
+        if _TASK_RE.match(line):
+            if seen == index:
+                target = n
+                break
+            seen += 1
+    if target is None:
+        return body
+
+    match = _TASK_RE.match(lines[target])
+    replacement = replace(match)
+    if replacement is None:
+        del lines[target]
+    else:
+        lines[target] = replacement
+    return "\n".join(lines)
+
+
+def set_item_checked(body: str, index: int, checked: bool) -> str:
+    """Tick or untick the `index`-th item, keeping its text, indent and bullet."""
+    return _rewrite(
+        body,
+        index,
+        lambda m: render_item(m.group("text") or "", checked, m.group("indent"), m.group("bullet")),
+    )
+
+
+def set_item_text(body: str, index: int, text: str) -> str:
+    """Replace the text of the `index`-th item, keeping its state and its bullet."""
+    return _rewrite(
+        body,
+        index,
+        lambda m: render_item(text.strip(), m.group("mark") in "xX", m.group("indent"), m.group("bullet")),
+    )
+
+
+def remove_item(body: str, index: int) -> str:
+    """Delete the `index`-th item, line and all."""
+    return _rewrite(body, index, lambda _m: None)
+
+
+def append_item(body: str, text: str, checked: bool = False) -> str:
+    """Add an item at the end of the body.
+
+    A blank line between prose and the list, nothing between consecutive items —
+    the layout `import_export._note_markdown` has always used when writing a checklist
+    out. That is not cosmetic: it is what the Alembic migration folds existing
+    `note_items` rows into AND what `derive::append_item` produces on every client, so
+    all three land on identical bodies. An export taken before the migration and one
+    taken after therefore differ in nothing.
+    """
+    line = render_item(text.strip(), checked)
+    trimmed = body.rstrip("\n")
+    if not trimmed.strip():
+        return line
+    follows_a_list = bool(_TASK_RE.match(trimmed.split("\n")[-1]))
+    return f"{trimmed}\n{line}" if follows_a_list else f"{trimmed}\n\n{line}"

src/thoughtsync/notes/helpers.py

@@ -3,6 +3,8 @@ board-filter narrowing, the owner-scoped fetch, and filename/slug sanitizers use
 both the attachment routes and the importer."""
 from __future__ import annotations
 
+from .checklist import strip_marker
+
 import os
 import re
 
@@ -19,29 +21,36 @@ VALID_FILTERS = {"active", "archived", "trash"}
 DISPLAY_TITLE_CAP = 200
 
 
-def derive_display_title(body: str | None, first_item: str | None = None) -> str:
-    """The note's display NAME: the first non-empty line of the body, else the first
-    checklist item's text (both trimmed and length-capped).
+def derive_display_title(body: str | None) -> str:
+    """The note's display NAME: the first line of the body that says anything.
 
-    There is no explicit title to prefer any more (M13 step 3) — a note is a body plus
-    optional items, and its name is simply the first thing written in it. Persisted as
-    notes.display_title so search results and export filenames have something to say.
+    There is no explicit title to prefer any more (M13 step 3) — a note is a body, and
+    its name is simply the first thing written in it. Persisted as notes.display_title
+    so search results and export filenames have something to say.
 
-    The item fallback is what step 2 bought: a note that is only a checklist would
-    otherwise have no name at all, which is exactly the hole that made removing the
-    title unsafe before checklists stopped being their own kind of thing.
+    The old `first_item` fallback is gone with M304: items ARE body lines now, so a
+    list-only note is named by its first item without anyone having to arrange it. What
+    replaced the fallback is stripping the task marker — calling that note "- [ ] milk"
+    would show someone the storage instead of the note — and skipping an EMPTY item, so
+    a half-typed list does not leave a note with no name.
 
-    Deterministic — a literal first line, never generated.
+    Mirrors `display_title` in core/src/local/store.rs. Deterministic — a literal first
+    line, never generated.
     """
     for line in (body or "").splitlines():
-        stripped = line.strip()
+        stripped = strip_marker(line.strip()).strip()
         if stripped:
             return stripped[:DISPLAY_TITLE_CAP]
-    return (first_item or "").strip()[:DISPLAY_TITLE_CAP]
+    return ""
 
 
 def is_empty_note(body: str | None, items: list | None = None) -> bool:
-    """Nothing worth keeping: no body text and no checklist items."""
+    """Nothing worth keeping: no body text and no checklist items.
+
+    `items` is still a separate argument because create still accepts them separately —
+    the importer holds a list, not a blob — and they are folded into the body only
+    after this check has decided the note is worth making at all.
+    """
     return not (body or "").strip() and not items
 
 

src/thoughtsync/notes/import_export.py

@@ -20,7 +20,6 @@ from ..config import Config
 from ..models.label import NoteLabel
 from ..models.note import Note
 from ..models.note_attachment import NoteAttachment
-from ..models.note_item import NoteItem
 from .helpers import (
     ALLOWED_IMAGE_MIMES,
     _attachment_ext,
@@ -28,11 +27,12 @@ from .helpers import (
     derive_display_title,
     is_empty_note,
 )
+from .checklist import append_item
 from .tags import _find_or_create_label, _reconcile_tags
 from .recurrence import normalize_recurrence
 
 
-def _note_markdown(note: Note, labels: list, items: list) -> str:
+def _note_markdown(note: Note, labels: list) -> str:
     """One note as a human-readable Markdown file with a small frontmatter block.
     The authoritative machine format is notes.json; this is for reading/portability."""
     fm = ["---"]
@@ -54,11 +54,9 @@ def _note_markdown(note: Note, labels: list, items: list) -> str:
     # are written, body first, with a blank line between them when there is.
     if note.body:
         fm.append(note.body)
-    if items:
-        if note.body:
-            fm.append("")
-        for it in items:
-            fm.append(f"- [{'x' if it['checked'] else ' '}] {it['text']}")
+    # No separate items block any more. The body already ends with those exact lines
+    # (M304) — this function is where their layout was decided, and appending them a
+    # second time would double every checklist in an export.
     return "\n".join(fm) + "\n"
 
 
@@ -294,9 +292,17 @@ async def _create_imported_note(
     if is_empty_note(body, item_texts):
         return False
 
+    # Items fold into the body, which is where a checklist lives now (M304). Done
+    # before the Note is built so display_title and _reconcile_tags both see the
+    # finished text — an imported item can carry a #tag like any other line.
+    for it in items:
+        text = (it.get("text") or "").strip()
+        if text:
+            body = append_item(body, text, bool(it.get("checked")))
+
     note = Note(
         owner_id=owner_id,
-        display_title=derive_display_title(body, item_texts[0] if item_texts else None),
+        display_title=derive_display_title(body),
         body=body,
         color=normalize_color(spec.get("color")),
         pinned=bool(spec.get("pinned")),
@@ -316,12 +322,7 @@ async def _create_imported_note(
     if spec.get("updated_at"):
         note.updated_at = spec["updated_at"]
     db.add(note)
-    await db.flush()  # assign note.id before items/labels/attachments/links
-
-    for pos, it in enumerate(items):
-        text = (it.get("text") or "").strip()
-        if text:
-            db.add(NoteItem(note_id=note.id, text=text, checked=bool(it.get("checked")), position=pos))
+    await db.flush()  # assign note.id before labels/attachments/links
 
     # Explicit (picker-style) labels are manual — via_tag=False. Inline #tags in the
     # body are handled by _reconcile_tags below, same as a normal create.

src/thoughtsync/notes/serialize.py

@@ -8,8 +8,8 @@ from sqlalchemy import select
 from ..models.label import Label, NoteLabel
 from ..models.note import Note
 from ..models.note_attachment import NoteAttachment
-from ..models.note_item import NoteItem
 from ..models.note_link_preview import NoteLinkPreview
+from .checklist import parse_items
 
 
 async def _labels_for_notes(db, note_ids: list) -> dict:
@@ -30,23 +30,23 @@ async def _labels_for_notes(db, note_ids: list) -> dict:
     return result
 
 
-def _serialize_item(item: NoteItem) -> dict:
-    return {"id": str(item.id), "text": item.text, "checked": item.checked, "position": item.position}
+def items_of(body: str | None) -> list[dict]:
+    """The note's checklist, read out of its body. No query, because there is no table.
 
+    Still emitted in the payload after M304, and that is not a second source of truth:
+    it is DERIVED on the way out, so it cannot disagree with the body it came from. It
+    saves every consumer that only wants to draw checkboxes from carrying a parser, and
+    the ones that do carry one (the native clients, the browser) are free to ignore it
+    and read the body.
 
-async def _items_for_notes(db, note_ids: list) -> dict:
-    """Map note_id -> [checklist items] in one query, ordered by position."""
-    result: dict = {}
-    if not note_ids:
-        return result
-    items = (
-        await db.scalars(
-            select(NoteItem).where(NoteItem.note_id.in_(note_ids)).order_by(NoteItem.position, NoteItem.created_at)
-        )
-    ).all()
-    for item in items:
-        result.setdefault(item.note_id, []).append(_serialize_item(item))
-    return result
+    The id is the item's ORDINAL, which is what the rewriters in `checklist.py` take,
+    so a client holding one can act on it directly. It also shifts when an item is
+    removed — every mutation returns the reloaded note for exactly that reason.
+    """
+    return [
+        {"id": str(i), "text": item.text, "checked": item.checked, "position": i}
+        for i, item in enumerate(parse_items(body))
+    ]
 
 
 def _attachment_url(note_id, att_id) -> str:
@@ -108,8 +108,7 @@ async def _serialize_note(db, note: Note) -> dict:
     data = note.serialize()
     labels = await _labels_for_notes(db, [note.id])
     data["labels"] = labels.get(note.id, [])
-    items = await _items_for_notes(db, [note.id])
-    data["items"] = items.get(note.id, [])
+    data["items"] = items_of(note.body)
     attachments = await _attachments_for_notes(db, [note.id])
     data["attachments"] = attachments.get(note.id, [])
     previews = await _previews_for_notes(db, [note.id])
@@ -120,14 +119,14 @@ async def _serialize_note(db, note: Note) -> dict:
 async def _serialize_notes(db, notes: list) -> list:
     ids = [n.id for n in notes]
     labels_map = await _labels_for_notes(db, ids)
-    items_map = await _items_for_notes(db, ids)
+
     attach_map = await _attachments_for_notes(db, ids)
     preview_map = await _previews_for_notes(db, ids)
     out = []
     for n in notes:
         data = n.serialize()
         data["labels"] = labels_map.get(n.id, [])
-        data["items"] = items_map.get(n.id, [])
+        data["items"] = items_of(n.body)
         data["attachments"] = attach_map.get(n.id, [])
         data["previews"] = preview_map.get(n.id, [])
         out.append(data)

src/thoughtsync/retention.py

@@ -32,7 +32,6 @@ from .db import session_scope
 from .models.label import NoteLabel
 from .models.note import Note
 from .models.note_attachment import NoteAttachment
-from .models.note_item import NoteItem
 from .models.note_link_preview import NoteLinkPreview
 from .models.note_revision import NoteRevision
 from .settings import get_setting
@@ -85,7 +84,6 @@ async def purge_note(db, note: Note, edited_at: datetime | None = None) -> None:
             # place would make the note reappear whole on the next sweep.
             logger.warning("couldn't remove attachment file %s during purge", a.path, exc_info=True)
     await db.execute(sa_delete(NoteAttachment).where(NoteAttachment.note_id == note.id))
-    await db.execute(sa_delete(NoteItem).where(NoteItem.note_id == note.id))
     await db.execute(sa_delete(NoteLabel).where(NoteLabel.note_id == note.id))
     await db.execute(sa_delete(NoteLinkPreview).where(NoteLinkPreview.note_id == note.id))
     await db.execute(sa_delete(NoteRevision).where(NoteRevision.note_id == note.id))

src/thoughtsync/revisions.py

@@ -0,0 +1,55 @@
+"""When a body change is worth keeping a version of.
+
+A note's body used to snapshot into `note_revisions` on EVERY write, which made a
+write expensive — and the clients compensated by writing as rarely as they could
+get away with, saving only when an editor closed. That is durability paying for
+version history: a crash mid-session lost everything typed, so that the revision
+list would stay tidy. The safety property is worth more than the feature it was
+subsidising.
+
+The rule here breaks that trade. A body change earns a snapshot only if it is the
+first one of an editing session, so a client may write as often as it likes.
+
+Session granularity falls out of the window rather than being declared. A snapshot
+stores the body as it was BEFORE the edit, so the first write of a sitting captures
+the note as you found it and every write after it inside the window adds nothing —
+one revision per sitting, with no "commit" flag for a client to send and no wire
+surface to carry it. That last part is why this is a time rule and not a protocol
+one: `sync.py` applies pushed bodies through the same check, so a client autosaving
+every second cannot make the server snapshot every second either.
+
+Deliberately NOT applied to restoring a revision. That is a considered act rather
+than a keystroke, and it snapshots unconditionally so restoring is itself undoable.
+"""
+from __future__ import annotations
+
+import uuid
+from datetime import datetime, timedelta, timezone
+
+from sqlalchemy import select
+
+from .models.note_revision import NoteRevision
+
+# How long one editing session is assumed to last. A constant rather than a setting:
+# it is not a preference anyone holds, and the value only has to be longer than a
+# sitting and shorter than the gap between two of them. Promote it to the settings
+# registry (rule 25) if that ever stops being true.
+REVISION_WINDOW_MINUTES = 10
+
+
+async def should_snapshot(db, note_id: uuid.UUID, old_body: str, new_body: str) -> bool:
+    """Whether `old_body` should be kept as a revision before `new_body` replaces it.
+
+    False when the text did not actually change — re-saving identical bytes is not a
+    version of anything — and False when this note already has a revision from the
+    current session.
+    """
+    if old_body == new_body:
+        return False
+    cutoff = datetime.now(timezone.utc) - timedelta(minutes=REVISION_WINDOW_MINUTES)
+    recent = await db.scalar(
+        select(NoteRevision.id)
+        .where(NoteRevision.note_id == note_id, NoteRevision.created_at >= cutoff)
+        .limit(1)
+    )
+    return recent is None

src/thoughtsync/sync.py

@@ -24,8 +24,8 @@ from .db import session_scope
 from .labeling import reconcile_manual_labels, resolve_owned_label_ids
 from .models.label import Label, NoteLabel
 from .models.note import Note
-from .models.note_item import NoteItem
 from .models.note_revision import NoteRevision
+from .revisions import should_snapshot
 from .notes import (
     _reconcile_tags,
     _serialize_notes,
@@ -62,8 +62,8 @@ MAX_PUSH = 1000  # per-batch change cap
 #
 # One bump for the pair: they landed in the same protocol generation, and nothing ever
 # ran against a half-applied v2.
-SYNC_PROTOCOL_VERSION = 2
-MIN_CLIENT_PROTOCOL_VERSION = 2
+SYNC_PROTOCOL_VERSION = 3
+MIN_CLIENT_PROTOCOL_VERSION = 3
 
 # Named capabilities beyond the base protocol. An ADDITIVE change earns a name
 # here rather than a min-version bump, so a newer client meeting an older server
@@ -212,49 +212,12 @@ def _assign_note_fields(note: Note, ch: dict) -> None:
         note.position = ch["position"]
 
 
-def _first_item_text(ch: dict) -> str:
-    """The first non-blank checklist item in a pushed change, or "".
-
-    Read straight from the payload rather than the database because the note's name is
-    computed BEFORE `_apply_note_items` has written anything — and a note whose body is
-    empty is named by its first item (M13 step 3).
-    """
-    items = ch.get("items")
-    if not isinstance(items, list):
-        return ""
-    for it in items:
-        if isinstance(it, dict):
-            text = (it.get("text") or "").strip()
-            if text:
-                return text
-    return ""
-
-
-async def _apply_note_items(db, note: Note, ch: dict) -> None:
-    """Replace the note's checklist items with the client's (items sync inline).
-
-    Applies to ANY note. This used to delete every item when the note wasn't
-    `kind == "list"`, which was survivable only because nothing could produce a note
-    holding both a body and items. M13 makes that the normal shape — a checklist is
-    something a note HAS, not something a note IS — and against that shape the old
-    guard was a data-loss path: the first sync after adding a checklist to a note
-    would have wiped it.
-
-    Removed ahead of the UI that can create the state, deliberately, so there is no
-    window in which the two disagree.
-    """
-    items = ch.get("items")
-    if not isinstance(items, list):
-        # Absent means "not telling us", not "empty". A client that omits the key
-        # leaves what the server has; only an explicit [] clears it.
-        return
-    await db.execute(sa_delete(NoteItem).where(NoteItem.note_id == note.id))
-    for pos, it in enumerate(items):
-        if not isinstance(it, dict):
-            continue
-        text = (it.get("text") or "").strip()
-        if text:
-            db.add(NoteItem(note_id=note.id, text=text, checked=bool(it.get("checked")), position=pos))
+# `_first_item_text` and `_apply_note_items` lived here until M304. Both existed for
+# one reason — a checklist was a table beside the body — and both are gone with it. A
+# pushed change carries its items as `- [ ] ` lines inside `body`, so applying them is
+# applying the body, and naming the note is reading its first line. A client that still
+# sends an `items` array is a v2 client, and the version floor below turns it away
+# before any of this runs.
 
 
 async def _apply_note_manual_labels(db, note: Note, ch: dict) -> None:
@@ -314,14 +277,18 @@ async def _apply_note(db, ch: dict) -> dict:
 
     old_body = note.body
     _assign_note_fields(note, ch)
-    note.display_title = derive_display_title(note.body, _first_item_text(ch))
+    note.display_title = derive_display_title(note.body)
     if edited_at is not None:
         note.updated_at = edited_at
-    # Non-destructive LWW: snapshot the overwritten server body into history.
-    if not creating and note.body != old_body:
+    # Non-destructive LWW: snapshot the overwritten server body into history —
+    # subject to the same session window as a direct edit (revisions.should_snapshot).
+    # This path is why the window is a time rule rather than a flag on the wire: a
+    # client autosaving every second pushes a body change every second, and without
+    # the check the SERVER would snapshot each one no matter how restrained the
+    # client's own store was being.
+    if not creating and await should_snapshot(db, note.id, old_body, note.body):
         db.add(NoteRevision(note_id=note.id, body=old_body))
     await db.flush()  # assign note.id before items/labels/links
-    await _apply_note_items(db, note, ch)
     await _reconcile_tags(db, note)
     await _apply_note_manual_labels(db, note, ch)
     await db.flush()

tests/test_integration.py

@@ -16,6 +16,7 @@ deployment has ever seen.
 from __future__ import annotations
 
 import uuid
+from datetime import datetime, timedelta, timezone
 
 import pytest
 import pytest_asyncio
@@ -25,19 +26,20 @@ from thoughtsync import ratelimit
 from thoughtsync.app import create_app
 from thoughtsync.db import dispose_engine, session_scope
 from thoughtsync.models.note import Note
-from thoughtsync.models.note_item import NoteItem
 from thoughtsync.models.user import User
 from thoughtsync.settings import get_setting, live, refresh_live, reset_live, set_settings
+from thoughtsync.notes.checklist import parse_items, set_item_checked
 from thoughtsync.notes.helpers import derive_display_title
 from thoughtsync.models.note_link_preview import NoteLinkPreview
-from thoughtsync.sync import _apply_note_items
+from thoughtsync.models.note_revision import NoteRevision
+from thoughtsync.revisions import REVISION_WINDOW_MINUTES, should_snapshot
 from thoughtsync.unfurl_queue import _unfurl_new_urls, detect_urls
 
 pytestmark = pytest.mark.integration
 
 # Every table the tests touch, child-first so FKs never block the truncate.
 # RESTART IDENTITY + CASCADE keeps this honest if a table gains children later.
-_TABLES = "notes, note_items, note_revisions, note_labels, note_link_previews, labels, users"
+_TABLES = "notes, note_revisions, note_labels, note_link_previews, labels, users"
 
 
 @pytest_asyncio.fixture
@@ -157,65 +159,55 @@ async def test_the_search_vector_was_rebuilt_over_the_name(db, owner):
     assert body_only == 1
 
 
-async def test_a_note_keeps_both_its_body_and_its_items(db, owner):
-    """The shape M13 step 2 made normal: a note HAS a checklist, it isn't one."""
-    note = Note(owner_id=owner.id, body="weekend shop", display_title="weekend shop")
-    db.add(note)
-    await db.flush()
-    db.add_all(
-        [
-            NoteItem(note_id=note.id, text="milk", position=0),
-            NoteItem(note_id=note.id, text="eggs", position=1),
-        ]
-    )
-    await db.commit()
+async def test_a_note_keeps_its_prose_on_both_sides_of_its_list(db, owner):
+    """The shape M304 made expressible at all.
 
-    items = (
-        await db.scalars(select(NoteItem).where(NoteItem.note_id == note.id).order_by(NoteItem.position))
-    ).all()
-    assert [i.text for i in items] == ["milk", "eggs"]
-    assert (await db.scalar(select(Note.body).where(Note.id == note.id))) == "weekend shop"
-
-
-async def test_sync_no_longer_deletes_items_from_a_note_with_a_body(db, owner):
-    """The data-loss path step 2 removed, pinned against a real database.
-
-    `_apply_note_items` used to delete every item when the note wasn't `kind = "list"`.
-    Nothing can produce that state any more, but this is the regression that would
-    have silently eaten a checklist, and it deserves a test that would catch its
-    return.
+    The old model could not hold this: a row had a position in a table and none in the
+    text, so a checklist could only ever render AFTER the body. Prose, list, prose is
+    the case that proves the storage changed, not just the styling.
     """
-    note = Note(owner_id=owner.id, body="packing", display_title="packing")
+    body = "weekend shop\n\n- [ ] milk\n- [x] eggs\n\nback before six"
+    note = Note(owner_id=owner.id, body=body, display_title=derive_display_title(body))
     db.add(note)
-    await db.flush()
-    db.add(NoteItem(note_id=note.id, text="socks", position=0))
     await db.commit()
 
-    # A change that says nothing about items must LEAVE them alone — absent means
-    # "not telling us", not "empty".
-    await _apply_note_items(db, note, {"body": "packing"})
-    await db.commit()
-    assert (await db.scalar(select(NoteItem.text).where(NoteItem.note_id == note.id))) == "socks"
-
-    # An explicit list replaces them.
-    await _apply_note_items(db, note, {"items": [{"text": "charger", "checked": True}]})
-    await db.commit()
-    rows = (await db.scalars(select(NoteItem).where(NoteItem.note_id == note.id))).all()
-    assert [(r.text, r.checked) for r in rows] == [("charger", True)]
+    stored = await db.scalar(select(Note.body).where(Note.id == note.id))
+    assert [(i.text, i.checked) for i in parse_items(stored)] == [("milk", False), ("eggs", True)]
+    assert stored.splitlines()[0] == "weekend shop"
+    assert stored.splitlines()[-1] == "back before six"
 
 
-async def test_a_note_with_only_items_still_has_a_name(db, owner):
-    """The hole that made removing the title unsafe until step 2 closed it."""
-    note = Note(owner_id=owner.id, body="", display_title="")
+async def test_ticking_an_item_is_a_body_edit(db, owner):
+    """What replaced `_apply_note_items`: there is no separate thing left to apply.
+
+    The regression that function guarded against — a sync silently eating a checklist
+    off a note that also had a body — cannot recur, because there is nothing to delete.
+    A pushed body either has the lines or it does not.
+    """
+    body = "packing\n\n- [ ] socks"
+    note = Note(owner_id=owner.id, body=body, display_title="packing")
     db.add(note)
-    await db.flush()
-    db.add(NoteItem(note_id=note.id, text="milk", position=0))
     await db.commit()
 
-    first = await db.scalar(
-        select(NoteItem.text).where(NoteItem.note_id == note.id).order_by(NoteItem.position).limit(1)
-    )
-    note.display_title = derive_display_title(note.body, first)
+    note.body = set_item_checked(note.body, 0, True)
+    await db.commit()
+
+    stored = await db.scalar(select(Note.body).where(Note.id == note.id))
+    assert stored == "packing\n\n- [x] socks"
+    assert parse_items(stored)[0].checked
+    # The prose is untouched — a tick rewrites one line, not the note.
+    assert stored.splitlines()[0] == "packing"
+
+
+async def test_a_note_with_only_a_list_still_has_a_name(db, owner):
+    """The hole that made removing the title unsafe, still closed — by a different
+    mechanism. There is no item table to fall back to any more; the name comes from
+    the first line with its marker stripped, because calling the note "- [ ] milk"
+    would show someone the storage instead of the note.
+    """
+    body = "- [ ] milk\n- [ ] eggs"
+    note = Note(owner_id=owner.id, body=body, display_title=derive_display_title(body))
+    db.add(note)
     await db.commit()
 
     assert (await db.scalar(select(Note.display_title).where(Note.id == note.id))) == "milk"
@@ -414,3 +406,70 @@ async def test_the_security_group_reaches_the_admin_ui(app_client, db):
         assert row["type"] == "int"
         assert row["minimum"] is not None and row["maximum"] is not None
         assert row["description"], f"{row['key']} has no description to explain itself"
+
+
+async def _revision_count(db, note_id) -> int:
+    rows = (await db.scalars(select(NoteRevision.id).where(NoteRevision.note_id == note_id))).all()
+    return len(rows)
+
+
+async def test_a_session_of_edits_costs_one_revision(db, owner):
+    """The change that makes autosave affordable.
+
+    Version history used to snapshot on EVERY body write, so the clients saved as
+    rarely as they could — only when an editor closed — and a crash mid-session lost
+    everything typed. Durability was paying for history. Now a sitting earns one
+    revision no matter how many times it is written, so a client can write whenever
+    it likes.
+    """
+    note = Note(owner_id=owner.id, body="one", display_title="one")
+    db.add(note)
+    await db.commit()
+
+    # A session's worth of autosaves.
+    for text_ in ("one two", "one two three", "one two three four"):
+        if await should_snapshot(db, note.id, note.body, text_):
+            db.add(NoteRevision(note_id=note.id, body=note.body))
+        note.body = text_
+        await db.commit()
+
+    assert await _revision_count(db, note.id) == 1
+
+    # And it is the body as it was BEFORE the sitting, not some midpoint — which is
+    # what makes one-per-session the useful granularity rather than an arbitrary one.
+    kept = (await db.scalars(select(NoteRevision.body).where(NoteRevision.note_id == note.id))).all()
+    assert kept == ["one"]
+
+
+async def test_rewriting_the_same_text_is_not_a_version(db, owner):
+    note = Note(owner_id=owner.id, body="unchanged", display_title="unchanged")
+    db.add(note)
+    await db.commit()
+
+    assert await should_snapshot(db, note.id, note.body, "unchanged") is False
+    assert await _revision_count(db, note.id) == 0
+
+
+async def test_a_later_sitting_earns_its_own_revision(db, owner):
+    """The window has to REOPEN, or a note edited daily would keep only its first
+    version forever — which would be a worse history than the one we replaced."""
+    note = Note(owner_id=owner.id, body="today", display_title="today")
+    db.add(note)
+    await db.flush()
+    # A revision from longer ago than one session: the clock is not mocked, the row
+    # is simply written with an older timestamp, which is what the query reads.
+    stale = datetime.now(timezone.utc) - timedelta(minutes=REVISION_WINDOW_MINUTES + 1)
+    db.add(NoteRevision(note_id=note.id, body="yesterday", created_at=stale))
+    await db.commit()
+
+    assert await should_snapshot(db, note.id, note.body, "tomorrow") is True
+
+
+async def test_a_revision_inside_the_window_blocks_another(db, owner):
+    note = Note(owner_id=owner.id, body="draft", display_title="draft")
+    db.add(note)
+    await db.flush()
+    db.add(NoteRevision(note_id=note.id, body="earlier", created_at=datetime.now(timezone.utc)))
+    await db.commit()
+
+    assert await should_snapshot(db, note.id, note.body, "draft revised") is False

tests/test_notes.py

@@ -5,12 +5,21 @@ import pytest
 from thoughtsync.app import create_app
 from thoughtsync.common import coerce_bool, parse_dt
 from thoughtsync.models.note import NOTE_COLORS, Note
+from thoughtsync.notes.checklist import (
+    append_item,
+    parse_items,
+    remove_item,
+    set_item_checked,
+    set_item_text,
+    strip_marker,
+)
 from thoughtsync.unfurl_queue import detect_urls
 from thoughtsync.notes import (
     _attachment_ext,
     _header_filename,
     _keep_spec,
     _native_spec,
+    _note_markdown,
     _safe_filename,
     _slugify,
     _usec_to_dt,
@@ -42,7 +51,7 @@ def test_all_note_routes_registered(app):
             "reorder_notes", "create_note",
             "get_note", "update_note", "list_revisions", "restore_revision",
             "set_note_labels", "add_item", "update_item", "delete_item",
-            "reorder_items", "upload_attachment", "get_attachment",
+            "upload_attachment", "get_attachment",
             "delete_attachment", "unfurl_link", "delete_preview", "trash_note",
             "restore_note", "delete_note",
         )
@@ -131,27 +140,32 @@ def test_derive_display_title_is_the_first_body_line():
     assert derive_display_title("\n   \nreal line\nmore") == "real line"
 
 
-def test_derive_display_title_falls_back_to_the_first_item():
-    # What step 2 bought: a note that is only a checklist still has a name. Without
-    # this it would have none at all, which is why the title could not go first.
-    assert derive_display_title("", "milk") == "milk"
-    assert derive_display_title("   \n  ", "  eggs  ") == "eggs"
-    # The body still wins when it has anything to say.
-    assert derive_display_title("shopping", "milk") == "shopping"
+def test_derive_display_title_names_a_list_only_note():
+    # The same property the old `first_item` fallback protected — a note that is only
+    # a checklist still has a name — reached a different way. Items ARE body lines now
+    # (M304), so the first one is simply the first line, with its marker stripped:
+    # calling the note "- [ ] milk" would show someone the storage instead of the note.
+    assert derive_display_title("- [ ] milk\n- [ ] eggs") == "milk"
+    assert derive_display_title("  * [x]   eggs  ") == "eggs"
+    # Prose still wins when it comes first, because it IS the first line.
+    assert derive_display_title("shopping\n\n- [ ] milk") == "shopping"
+    # An EMPTY item does not name the note "" — a half-typed list still has a name.
+    assert derive_display_title("- [ ]\n- [ ] eggs") == "eggs"
 
 
 def test_derive_display_title_empty():
     assert derive_display_title(None) == ""
     assert derive_display_title("") == ""
-    assert derive_display_title("   \n  ", None) == ""
-    assert derive_display_title("   \n  ", "   ") == ""
+    assert derive_display_title("   \n  ") == ""
+    # A list of nothing but empty items is still a note with no name.
+    assert derive_display_title("- [ ]\n- [ ]") == ""
 
 
 def test_derive_display_title_caps_length():
     long = "x" * 300
     assert derive_display_title(long) == "x" * 200
-    # the item fallback is capped on the same rule
-    assert derive_display_title("", long) == "x" * 200
+    # A first line that happens to be an item is capped on the same rule.
+    assert derive_display_title(f"- [ ] {long}") == "x" * 200
 
 
 def test_parse_tags():
@@ -406,3 +420,153 @@ def test_detect_urls_ignores_non_http():
     assert detect_urls("ftp://example.com and mailto:a@b.c and bare example.com") == []
     assert detect_urls(None) == []
     assert detect_urls("") == []
+
+
+# --- checklist items: the body IS the checklist (M304) -----------------------
+#
+# The same table of cases as core/src/local/derive.rs. Deliberately duplicated
+# rather than shared: the point of three implementations is that each is checked
+# against the same grammar, and a test that only ran once would not catch the two
+# drifting apart.
+
+
+def test_parse_items_reads_a_list_out_of_prose():
+    body = "shopping\n\n- [ ] milk\n- [x] eggs"
+    assert [(i.text, i.checked) for i in parse_items(body)] == [("milk", False), ("eggs", True)]
+
+
+def test_parse_items_between_paragraphs():
+    # The case a side table could not express, which is the whole reason for M304.
+    assert [i.text for i in parse_items("before\n- [ ] middle\nafter")] == ["middle"]
+
+
+@pytest.mark.parametrize(
+    "body",
+    [
+        "-[ ] no space after the dash",
+        "- [] empty brackets",
+        "- [ ]no space after the brackets",
+        "- [y] not a mark",
+        "a [ ] mid sentence",
+        "[ ] no bullet at all",
+    ],
+)
+def test_parse_items_rejects_near_misses(body):
+    assert parse_items(body) == []
+
+
+def test_parse_items_accepts_star_bullets_and_indentation():
+    # `*` because markdown.ts already takes it for a plain bullet.
+    body = "* [ ] star\n    - [x] indented"
+    assert [(i.text, i.checked) for i in parse_items(body)] == [("star", False), ("indented", True)]
+
+
+def test_an_empty_item_is_still_an_item():
+    # What pressing Enter on a list leaves behind.
+    assert [i.text for i in parse_items("- [ ]")] == [""]
+    assert [i.text for i in parse_items("- [ ] ")] == [""]
+
+
+def test_uppercase_x_parses_and_normalises_on_rewrite():
+    assert parse_items("- [X] done")[0].checked
+    assert set_item_checked("- [X] done", 0, True) == "- [x] done"
+
+
+def test_rewriters_preserve_indent_bullet_and_neighbours():
+    assert set_item_checked("  * [ ] milk", 0, True) == "  * [x] milk"
+    assert set_item_text("- [x] old", 0, "new") == "- [x] new"
+    assert remove_item("keep\n- [ ] drop\n- [ ] stay", 0) == "keep\n- [ ] stay"
+    # Addressed by ITEM, not by line.
+    assert set_item_checked("note\n- [ ] a\nprose\n- [ ] b", 1, True) == "note\n- [ ] a\nprose\n- [x] b"
+
+
+def test_a_stale_index_does_nothing():
+    # The index comes from a client that may be a moment behind. A late request
+    # should be inert, not a 500.
+    body = "- [ ] only"
+    assert set_item_checked(body, 7, True) == body
+    assert remove_item(body, 7) == body
+    assert set_item_text(body, 7, "x") == body
+
+
+def test_a_plain_body_is_returned_unchanged():
+    body = "just prose\nwith two lines"
+    assert set_item_checked(body, 0, True) == body
+    assert remove_item(body, 0) == body
+
+
+def test_append_item_spacing():
+    # Prose, blank line, list — the layout _note_markdown has always exported, and
+    # what the migration folds existing rows into.
+    assert append_item("a note", "milk") == "a note\n\n- [ ] milk"
+    # Nothing between consecutive items.
+    assert append_item("a note\n\n- [ ] milk", "eggs") == "a note\n\n- [ ] milk\n- [ ] eggs"
+    # A list-only note starts at the first line.
+    assert append_item("", "milk") == "- [ ] milk"
+    assert append_item("\n\n", "milk") == "- [ ] milk"
+    # Carries state, which is what the migrations need of it.
+    assert append_item("", "done", True) == "- [x] done"
+
+
+def test_strip_marker():
+    assert strip_marker("- [x] milk") == "milk"
+    assert strip_marker("just prose") == "just prose"
+    assert strip_marker("- [ ]") == ""
+
+
+def test_the_migration_folds_exactly_like_the_app():
+    """0027 inlines its own copy of append_item, deliberately — a migration has to keep
+    producing what it produced the day it ran, so it must not follow the app if the
+    app's spacing ever changes. This is what keeps the copy honest until then."""
+    import importlib.util
+    from pathlib import Path
+
+    path = Path(__file__).resolve().parents[1] / "alembic" / "versions" / "0027_checklist_items_into_body.py"
+    spec = importlib.util.spec_from_file_location("_m0027", path)
+    module = importlib.util.module_from_spec(spec)
+    spec.loader.exec_module(module)
+
+    for body, text, checked in [
+        ("a note", "milk", False),
+        ("a note\n\n- [ ] milk", "eggs", True),
+        ("", "milk", False),
+        ("\n\n", "milk", False),
+        ("prose\n", "  padded  ", True),
+    ]:
+        assert module._append_item(body, text, checked) == append_item(body, text, checked)
+
+
+# --- import/export: the body already carries the list ------------------------
+
+
+def test_note_markdown_writes_a_checklist_once():
+    """The export used to append the items after the body. The body IS them now
+    (M304), so the old branch would have doubled every checklist in an export — and
+    doubled it again on the next re-import."""
+    note = Note(
+        display_title="shopping",
+        body="shopping\n\n- [ ] milk\n- [x] eggs",
+        color="default",
+        pinned=False,
+        archived=False,
+    )
+    out = _note_markdown(note, [])
+    assert out.count("- [ ] milk") == 1
+    assert out.count("- [x] eggs") == 1
+    # And in place, under the note's own first line rather than in a block of its own.
+    assert out.rstrip().endswith("shopping\n\n- [ ] milk\n- [x] eggs")
+
+
+def test_native_spec_of_a_current_export_folds_nothing():
+    # Today's export carries no `items` key, because the body has the lines. An empty
+    # list is what stops _insert_note folding them in a second time.
+    assert _native_spec({"body": "a\n\n- [ ] milk"})["items"] == []
+
+
+def test_native_spec_of_a_pre_m304_export_still_carries_its_items():
+    # An export taken BEFORE this milestone has a body with no task lines and a
+    # separate items array. Importing one has to put the checklist back — which is
+    # the same fold the Keep importer does, and the reason _insert_note still accepts
+    # items at all.
+    old = {"body": "shopping", "items": [{"text": "milk", "checked": True}]}
+    assert _native_spec(old)["items"] == [{"text": "milk", "checked": True}]