diff --git a/backend/app/services/migrators/gs_ingest.py b/backend/app/services/migrators/gs_ingest.py
index b7a3d88..18b832a 100644
--- a/backend/app/services/migrators/gs_ingest.py
+++ b/backend/app/services/migrators/gs_ingest.py
@@ -115,7 +115,7 @@ async def migrate_async(
         encrypted = fc_crypto.encrypt(cred["plaintext"])
         db.add(Credential(
             platform=cred["platform"],
-            kind=cred.get("credential_type") or "cookies",
+            credential_type=cred.get("credential_type") or "cookies",
             encrypted_blob=encrypted,
             expires_at=cred.get("expires_at"),
         ))
diff --git a/backend/app/services/migrators/verify.py b/backend/app/services/migrators/verify.py
index df8c951..52bf37c 100644
--- a/backend/app/services/migrators/verify.py
+++ b/backend/app/services/migrators/verify.py
@@ -18,7 +18,7 @@ async def verify_async(db: AsyncSession, *, expected: dict | None = None) -> dic
 
     checks = {
         "artist_subscriptions": (
-            select(func.count(Artist.id)).where(Artist.is_subscription == True)
+            select(func.count(Artist.id)).where(Artist.is_subscription.is_(True))
         ),
         "source_count": select(func.count(Source.id)),
         "credential_count": select(func.count(Credential.id)),
@@ -51,12 +51,15 @@ async def verify_sha256_sample(
     samples: list[dict] = []
     for img_id, path, expected_sha in rows:
         p = Path(path)
-        if not p.exists():
+        # Sync stdlib filesystem ops are intentional: this verify pass runs
+        # inside a Celery task under asyncio.run; no other awaitables compete
+        # for the loop. Same pattern as download_service.py.
+        if not p.exists():  # noqa: ASYNC240
             missing += 1
             samples.append({"id": img_id, "path": path, "result": "missing"})
             continue
         h = hashlib.sha256()
-        with p.open("rb") as f:
+        with p.open("rb") as f:  # noqa: ASYNC230
             for chunk in iter(lambda: f.read(65536), b""):
                 h.update(chunk)
         if h.hexdigest() == expected_sha:
diff --git a/backend/app/tasks/migration.py b/backend/app/tasks/migration.py
index dd200bd..bdedb93 100644
--- a/backend/app/tasks/migration.py
+++ b/backend/app/tasks/migration.py
@@ -20,15 +20,10 @@ from ..celery_app import celery
 from ..config import get_config
 from ..models import MigrationRun
 from ..services.credential_crypto import CredentialCrypto
-from ..services.migrators import (
-    backup as backup_mod,
-    gs_ingest,
-    ir_ingest,
-    ml_queue,
-    rollback as rollback_mod,
-    tag_apply,
-    verify,
-)
+from ..services.migrators import backup as backup_mod
+from ..services.migrators import gs_ingest, ir_ingest, ml_queue
+from ..services.migrators import rollback as rollback_mod
+from ..services.migrators import tag_apply, verify
 
 log = logging.getLogger(__name__)
 
diff --git a/tests/test_api_migrate.py b/tests/test_api_migrate.py
index 0c7bbf2..dffb529 100644
--- a/tests/test_api_migrate.py
+++ b/tests/test_api_migrate.py
@@ -3,15 +3,23 @@ import io
 import json
 
 import pytest
+from werkzeug.datastructures import FileStorage
 
 import backend.app.tasks.migration  # noqa: F401 — register celery task
-
 from backend.app import create_app
 from backend.app.celery_app import celery
 
 pytestmark = pytest.mark.integration
 
 
+def _file_storage(payload: dict, filename: str = "export.json") -> FileStorage:
+    return FileStorage(
+        stream=io.BytesIO(json.dumps(payload).encode("utf-8")),
+        filename=filename,
+        content_type="application/json",
+    )
+
+
 @pytest.fixture
 async def app():
     return create_app()
@@ -46,7 +54,7 @@ async def test_post_rejects_unknown_kind(client):
 
 @pytest.mark.asyncio
 async def test_post_ingest_rejects_missing_file(client):
-    resp = await client.post("/api/migrate/gs_ingest", data={})
+    resp = await client.post("/api/migrate/gs_ingest", form={})
     assert resp.status_code == 400
     body = await resp.get_json()
     assert body["error"] == "missing_export_file"
@@ -67,11 +75,11 @@ async def test_post_ingest_accepts_multipart_file(client, monkeypatch):
         "source_app": "gallerysubscriber", "schema_version": 1,
         "subscriptions": [], "credentials": [],
     }
-    data = {
-        "export_file": (io.BytesIO(json.dumps(export).encode()), "gs-export.json"),
-        "dry_run": "false",
-    }
-    resp = await client.post("/api/migrate/gs_ingest", files=data)
+    resp = await client.post(
+        "/api/migrate/gs_ingest",
+        form={"dry_run": "false"},
+        files={"export_file": _file_storage(export, "gs-export.json")},
+    )
     assert resp.status_code == 202
 
 
@@ -85,11 +93,11 @@ async def test_post_apply_without_backup_rejected(client, monkeypatch):
         "source_app": "gallerysubscriber", "schema_version": 1,
         "subscriptions": [], "credentials": [],
     }
-    data = {
-        "export_file": (io.BytesIO(json.dumps(export).encode()), "gs-export.json"),
-        "dry_run": "false",
-    }
-    resp = await client.post("/api/migrate/gs_ingest", files=data)
+    resp = await client.post(
+        "/api/migrate/gs_ingest",
+        form={"dry_run": "false"},
+        files={"export_file": _file_storage(export, "gs-export.json")},
+    )
     assert resp.status_code == 400
     body = await resp.get_json()
     assert body["error"] == "no_backup"
@@ -109,11 +117,11 @@ async def test_post_dry_run_allowed_without_backup(client, monkeypatch):
         "source_app": "gallerysubscriber", "schema_version": 1,
         "subscriptions": [], "credentials": [],
     }
-    data = {
-        "export_file": (io.BytesIO(json.dumps(export).encode()), "gs-export.json"),
-        "dry_run": "true",
-    }
-    resp = await client.post("/api/migrate/gs_ingest", files=data)
+    resp = await client.post(
+        "/api/migrate/gs_ingest",
+        form={"dry_run": "true"},
+        files={"export_file": _file_storage(export, "gs-export.json")},
+    )
     assert resp.status_code == 202