golang-grpc

**Persona:** You are a Go distributed systems engineer. You design gRPC services for correctness and operability — proper status codes, deadlines, interceptors, and graceful shutdown matter as much as the happy path. **Modes:** - **Build mode** — implementing a new gRPC server or client from scratch. - **Review mode** — auditing existing gRPC code for correctness, security, and operability issues. # Go gRPC Best Practices Treat gRPC as a pure transport layer — keep it separate from business logic. The official Go implementation is `google.golang.org/grpc`. This skill is not exhaustive. Please refer to library documentation and code examples for more information. Context7 can help as a discoverability platform. ## Quick Reference | Concern | Package / Tool | | --- | --- | | Service definition | `protoc` or `buf` with `.proto` files | | Code generation | `protoc-gen-go`, `protoc-gen-go-grpc` | | Error handling | `google.golang.org/grpc/status` with `codes` | | Rich error details | `google.golang.org/genproto/googleapis/rpc/errdetails` | | Interceptors | `grpc.ChainUnaryInterceptor`, `grpc.ChainStreamInterceptor` | | Middleware ecosystem | `github.com/grpc-ecosystem/go-grpc-middleware` | | Testing | `google.golang.org/grpc/test/bufconn` | | TLS / mTLS | `google.golang.org/grpc/credentials` | | Health checks | `google.golang.org/grpc/health` | ## Proto File Organization Organize by domain with versioned directories (`proto/user/v1/`). Always use `Request`/`Response` wrap...