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bulkhead
Separate pools so one noisy feature cannot sink the rest. Ships use them so one leak does not flood every compartment.
What is bulkhead?
A bulkhead isolates resources: its own thread pool, connection pool, or queue. A slow export cannot borrow every database connection from checkout. Isolation is a limit, so the limited part fails first and alone.
Why does bulkhead matter when vibe coding?
Models share one HTTP client and one pool for everything. A partner API hangs and checkout cannot get a socket. Name the pool per dependency.
How do you do bulkhead?
Give the risky or slow dependency its own small pool and timeout. When that pool is full, that feature fails. The rest keep their connections.
How do you ask a model for bulkhead?
Bulkhead (dependency) onto its own connection pool and timeout. If that pool is exhausted, fail (that feature) only. Do not let it take connections from (checkout).
What goes wrong with bulkhead?
Ten bulkheads that together exceed the database’s max connections. You isolated the app and DDoSed the database. The sum of pools must fit under the server limit.