Boundary
Coordination is now a layer of its own. Workers no longer infer ownership from memory or timing; the coordinator records it.
What this adds
Coordinate claims and handoffs.
This lab introduces a queue, worker identities, and claim records. The coordinator does not need to be smart. It just needs to stop duplicate claims and leave a readable history behind.
This is where multi-worker systems stop being theory and start needing explicit coordination.
Done when
Two workers can take different ready tasks and the queue still reads like one coherent workflow instead of a race condition.
Real-world analog
GitHub Actions is the everyday comparison: jobs, runners, queues, and orchestration around independent workers.
Why this matters
Once more than one worker exists, ownership and handoffs become first-class architecture concerns.