# Distributed Lock — Manual Review Checklist

## Timeout Strategy
- [ ] Lock TTL defined and justified (not arbitrary)
- [ ] TTL exceeds maximum expected operation time
- [ ] Watchdog/refresh mechanism if operation may exceed TTL
- [ ] Lock auto-releases on process crash (not permanent deadlock)

## Release Mechanism
- [ ] Lock released by the same instance that acquired it (ownership check)
- [ ] Release is atomic (check-then-release is not atomic — use Lua script or compare-and-delete)
- [ ] Lock release in finally/defer block guaranteed to execute

## Retry Strategy
- [ ] Retry with exponential backoff, not infinite retry
- [ ] Maximum retry count or timeout defined
- [ ] Failed lock acquisition returns clear error (not silent fallback)

## Granularity & Deadlock
- [ ] Lock key granularity appropriate (per-resource, not global)
- [ ] Multiple lock acquisition order consistent (prevents deadlock)
- [ ] No nested locks on same resource
- [ ] Lock contention monitored/metrics available