golang-context

To propagate context in Go, wire r.Context() from HTTP handlers and pass the same context.Context to downstream service calls and database queries using their *Context variants to ensure graceful cancellation and tracing.

The safest way to use context values for request IDs in distributed systems is by storing them with unexported keys, preventing collisions and ensuring safe tracing across service boundaries.

To set timeouts and cancellation for long-running tasks in Go, apply context.WithCancel, context.WithTimeout, or context.WithDeadline to model work boundaries and trigger graceful shutdowns when limits are exceeded.

You should use context.WithoutCancel in Go when spawning background tasks that must continue running independently of the parent request's cancellation signal, detaching the lifecycle from the incoming HTTP request.

Cancellation breaks in Go HTTP services when context.Context is not propagated correctly, requiring you to pass the same context to downstream service and database calls using their *Context variants to maintain the cancellation chain.

Yes, this Skill covers context usage for internal libraries and distributed systems, applying idiomatic patterns for cancellation, deadlines, and request-scoped values across HTTP servers and databases.