[RFC] Folder Session & Migration Mode — Optional Hybrid Catalog Architectur

[Lorenzoeffe]

Hello everyone 👋
I’m Lorenzo Fontanella, and this RFC proposes an optional Folder Session Mode for Darktable — a non-disruptive addition that lets users work directly from filesystem folders, without mandatory import, while keeping the classic catalog unchanged.

Each folder becomes a self-contained “session” with:

• PREVIEWS/ — JPEG previews
• PREVIEWS/settings/ — centralized sidecars
• session_info.yaml — human-readable mini catalog

The global DB acts as a lightweight index of pointers.

Benefits

• Cleaner folders, no sidecar clutter
• Lightweight, faster DB
• Portable YAML catalogs
• Interoperability (RawTherapee, DxO, Capture One, Lightroom)

UI enhancement

Adds a preference filmstrip_auto_scroll=false in Lighttable to disable automatic recentering.

Optional mode

Users can continue working exactly as before.

Repository

Full RFC docs, source code, and patch examples:
👉 https://github.com/tuonomeutente/darktable-folder-session-core-rfc

Feedback and technical insights are very welcome!
— Lorenzo Fontanella
📧 fontanellalorenzo@gmail.com · 🌐 www.lorenzofontanella.it

Full RFC and source code:
https://github.com/tuonomeutente/darktable-folder-session-core-rfc