OpenAIVerified interview challenge
Implement a fault-tolerant work queue
Keep an in-memory job queue consistent through successful work, failures and expired reservations.
Unlock with Full AccessThe challenge
Build an in-memory queue whose jobs can be reserved, succeed, fail or time out. Later requirements add dependencies, so a job's readiness depends on more than whether it has been enqueued.
Reason about ownership, retries and completion as operations advance the supplied clock. There is no real waiting or worker-thread setup, which keeps the exercise focused on whether the queue's state transitions are correct.
What you'll practise
Reservation lifecycle
Keep retries and expired work consistent with completed and exhausted jobs.
Dependency eligibility
Allow work to proceed only when the required prior jobs satisfy the contract.
Current partFurther parts unlock as you progress
solution.pyPython 3.13
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