The media/data location is no longer configurable — DATA_DIR is a fixed constant (/var/thoughtsync) and THOUGHTSYNC_MEDIA_ROOT is removed, so a mutable path can't drift from where the volume is mounted. media_root() = DATA_DIR/media. Both compose files drop THOUGHTSYNC_DATA_DIR and mount the data volume at /var/thoughtsync (was the contradictory /data). conftest drops the stale MEDIA_ROOT monkeypatch (create_app never reads DATA_DIR). Net env surface: THOUGHTSYNC_DATABASE_URL (required) + THOUGHTSYNC_SECRET_KEY (optional break-glass). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01FRgehjoz7Yv8LkUfADxACm