go-programminglisted

# Go Programming ## Operating Rules - Inspect `go.mod`, package layout, tests, and existing style before changing code. - Prefer small interfaces at consumer boundaries, explicit errors, table-driven tests, and simple composition over abstraction. - Preserve exported API compatibility unless the user asks for a breaking change. - Run targeted `go test` first, then wider tests when feasible. Use `go test -race` for concurrency changes when practical. ## Workflow 1. Build context with `rg --files`, `go list ./...`, and targeted reads of affected packages. 2. Identify package boundaries, public types, side effects, and concurrency ownership. 3. Implement the smallest cohesive change with clear errors and context-aware cancellation. 4. Add or update tests for success paths, failure paths, edge cases, and races. 5. Verify with formatting, tests, vet/static analysis if available, and a concise summary of risks. ## Go Standards - Use `context.Context` as the first parameter for request-scoped work. - Wrap errors with `%w` when callers can act on the cause; avoid string matching. - Keep goroutine lifecycle explicit with cancellation, bounded queues, and ownership of channel close. - Avoid package globals unless they are immutable constants or intentionally shared. - Use benchmarks and profiles before performance rewrites.