Custom plugins

Beyond the built-ins, memcal loads ~/.memcal/plugins/*.py plus anything registered through the memcal.sources entry-point group. Start from examples/plugins/rss.py — a small complete source.

Pick the transport shape that matches the platform (Observe): a plain Source with fetch for simple feeds (the RSS example is one), PolledSource for anything with a conversation listing and history, StreamSource for ordered or destructive queues. Implement the shape's hooks plus contact/handle mapping and check; watermarks, budgets, rounds, dedupe, gating, spooling, and freshness all come from the shared path.

Checklist before relying on a custom source:

1. memcal sources reports it usable (or the exact gap).
2. memcal ingest <name> --limit 20 archives and queues sane lines.
3. memcal gatecheck --stream <name> shows the gate admitting the right shape.
4. memcal dream --dry-run prices the resulting bundles.

Authoring details: Custom sources.