0145 — `claimed` advances at claim time, before processing, with no lease
Edit this pagePosted: 2026-09-08
Context. ClaimMessagesWithCursor advances claimed atomically when the range is handed out, before any message is processed, and nothing yet records who holds the range or for how long.
Decision. Ship the happy path that way: claim advances the read frontier immediately; no lease, no reclaim.
Consequences. A crash after claiming but before committing strands (committed, claimed] — the next claim reads above claimed and skips those offsets, so they are lost to the group. This is the known, intended hole of a happy-path-only design, accepted to keep the claim a single UPDATE … RETURNING. Superseded by the range lease work, which exists precisely to make the claimed-but-uncommitted window crash-safe and reclaimable.