# Timeout and Deadline Propagation ## Intent Bound waiting and propagate remaining time across dependent operations. ## Problem and forces Unbounded waits consume resources and downstream calls can outlive the user's useful budget. ## Applicability Use for every remote or potentially blocking dependency with a justified latency budget. ## When not to use Avoid one arbitrary timeout copied across operations with different service objectives. ## Benefits Limits resource retention and supports predictable failure. ## Liabilities Incorrect values cause premature failure or continued overload. ## Implementation considerations Prefer an end-to-end deadline, reserve cleanup time, cancel downstream work, and observe timeout causes. ## Credible alternatives Asynchronous queue, polling, streaming, or explicit long-running job contract. ## Related patterns Retry and Backoff, Circuit Breaker. ## Architecture interview questions What is the end-to-end latency budget, and how is remaining time propagated?