grpc-golang

# gRPC Golang (gRPC-Go) ## Overview Comprehensive guide for designing and implementing production-grade gRPC services in Go. Covers contract standardization with Buf, transport layer security via mTLS, and deep observability with OpenTelemetry interceptors. ## Use this skill when - Designing microservices communication with gRPC in Go. - Building high-performance internal APIs using Protobuf. - Implementing streaming workloads (unidirectional or bidirectional). - Standardizing API contracts using Protobuf and Buf. - Configuring mTLS for service-to-service authentication. ## Do not use this skill when - Building pure REST/HTTP public APIs without gRPC requirements. - Modifying legacy `.proto` files without the ability to introduce a new API version (e.g., `api.v2`) or ensure backward compatibility. - Managing service mesh traffic routing (e.g., Istio/Linkerd), which is outside the application code scope. ## Step-by-Step Guide 1. **Confirm Technical Context**: Identify Go version, gRPC-Go version, and whether the project uses Buf or raw protoc. 2. **Confirm Requirements**: Identify mTLS needs, load patterns (unary/streaming), SLOs, and message size limits. 3. **Plan Schema**: Define package versioning (e.g., `api.v1`), resource types, and error mapping. 4. **Security Design**: Implement mTLS for service-to-service authentication. 5. **Observability**: Configure interceptors for tracing, metrics, and structured logging. 6. **Verification**: Always run `buf lint` and brea...