Go Standard Library

Go standard library patterns

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Go Standard Library · balanced balanced

- Use `http.NewServeMux()` (Go 1.22+) with method-based routing: `mux.HandleFunc("GET /users/{id}", handler)`.

- Always pass `context.Context` as the first parameter — use `r.Context()` in handlers and propagate through the call chain.

- Use `http.HandlerFunc` for simple handlers and `http.Handler` interface for stateful handlers with injected dependencies.

- Use `encoding/json.NewDecoder(r.Body)` for request parsing and `json.NewEncoder(w).Encode()` for responses — set `Content-Type` header first.

- Use `context.Context` for request-scoped data, cancellation, and timeouts across API boundaries.

- Use `io.Reader` and `io.Writer` interfaces for composable I/O operations.

- Use `sync` package primitives (`Mutex`, `WaitGroup`, `Once`) for concurrency control.

- Structure packages by domain. Expose small, stable interfaces.