The Lock That Never Let Go

Nightly reconcile throws on bad rows. The on-call sees the lock held for hours with no owner process. Success path releases. The catch path does not.

Initial failing signallock stuck after thrown jobExpected behavior: A second run acquires the lock after the first run fails. · actual behavior: The lock remains held after the first run fails.

Progress

1Reproduce the bugRun checks

2Edit the fixOpen

3Pass checksOpen

4Submit fixOpen

Reproduction Steps

Run withLock with a function that throws.
Try withLock again for the same key.
The second call should acquire after the first failure.

Focus Mode

Start

src/mutex.ts
src/jobs.ts

Likely area

src/mutex.ts
src/jobs.ts
src/runner.ts

Challenge Coach

Hints reveal broad direction first, then narrow toward the suspect path without showing hidden tests or exact solution code.

TopicEvents & Concurrency

DifficultyMedium

Est. time15 min

Workspacepreparing

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Evidence Map

Failing signal loaded from challenge API
Workspace files loaded from workspace API
Results rendered only after API run/submit

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workspace

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