Reclaim expired assignments using current row authority
A sweep selects expired jobs, then reclaims one that was renewed before its update executes.
- Focused work estimate
- 3h 30m + prerequisites
- Priority in the scenario
- Medium
- Engineering practice
- Concurrency · Recovery
Estimated field mix
- Database engineering70%
- Distributed systems30%
Field percentages are editorial estimates of the ticket's engineering focus. They total 100%; they are not measured time, proficiency scores, or ownership evidence.
Review it, then add it to your workspace.
The board opens an editable draft; nothing is saved until you confirm it. Sign-in and workspace permissions apply, and Demo boards remain ephemeral.
Project context
A fictional inspection service assigns review jobs to staff. Polling clients sometimes claim the same job and a disconnected client can finish work after reassignment.
Setup prerequisites
- Create synthetic jobs and two independent database clients.
- Use explicit state methods and an injected clock.
Preceding work
Complete these dependencies, or supply their agreed outputs before taking this ticket.
- ACLAIM-101 · Define assignment states and their required database fields
- ACLAIM-102 · Order eligible jobs with a stable tie break
- ACLAIM-103 · Scope work assignment queries to the operator's organization
- ACLAIM-104 · Claim one pending job atomically under competing pollers
- ACLAIM-105 · Issue a monotonically increasing assignment generation on every reclaim
- ACLAIM-106 · Renew assignment leases without extending a completed job
- ACLAIM-107 · Finish a job and publish its result reference in one transaction
Acceptance criteria
- Recheck generation, assigned state and expiry in the reclaim update.
- Record previous ownership as immutable history.
- Bound each sweep and expose skipped renewals.
Implementation constraints
- Use a controlled clock and barrier for the renewal race.
Verification to include
- Reclaim a truly expired assignment.
- Renew between scan and update and verify reclaim skips it.
Deliverables
- Expiry reclaimer and race regression
Rollout and recovery
Dry-run selected rows first; pause sweeps when clock or ownership checks disagree.
Value of the work
For the engineer: Practice database concurrency, leases and transactional invariants.
For the team: Review whether assignment authority remains reliable during contention and recovery.
Evidence boundaries
Outcome Evidence: Tests, patches, and runbooks are requested deliverables. They become Outcome Evidence only through a qualified Mission and immutable Evidence IDs.
Ownership Evidence: Independent adaptation must be observed under a declared verification policy and cite immutable Evidence IDs. Completing a planning ticket establishes no Ownership Evidence.