Golang Context

Teaches Claude how to handle context.Context idiomatically in Go: propagation through call chains, cancellation patterns, timeouts, and context values. The core principle is simple but easy to mess up: pass the same context through your entire request lifecycle, never create a fresh context.Background() mid-chain, and always defer cancel(). Covers the gotchas like when to use TODO() versus Background(), why you shouldn't store contexts in structs, and how to use context values without namespace collisions. Includes patterns for HTTP handlers, database calls, and cross-service tracing. Most useful when you're building services that need proper cancellation propagation or you keep getting context usage wrong in code reviews.