Golang Structs Interfaces (Grade A)Security-tested development skill for Claude AI. Grade A. Golang struct and interface design patterns — composition, embedding, type assertions, type switches, interface segregation, dependency inject

Golang Structs Interfaces is a security-tested development skill for designing Go types, defining or implementing interfaces, and embedding structs or interfaces. It focuses on composition, embedding, type assertions, type switches, interface segregation, dependency injection via interfaces, struct field tags, and pointer vs value receivers. The skill is designed for Claude Code or similar AI coding agents and for projects using Golang. The skill emphasizes the importance of keeping interfaces small, with 1-3 methods, to make them easier to implement, mock, and compose. It suggests composing larger interfaces from smaller ones, defining interfaces where they are consumed, and avoiding importing a package just for its interface. The skill also recommends accepting interface parameters for flexibility and returning concrete types for clarity. The design principles outlined in the skill include starting with concrete types and extracting an interface when a second consumer or a test mock is needed. It warns against creating interfaces prematurely, as this can add indirection without value. The skill provides examples of how to define interfaces, compose them, and use them in functions to achieve flexibility and clarity. The skill is designed to be used when designing Go types, defining or implementing interfaces, embedding structs or interfaces, writing type assertions or type switches, adding struct field tags for JSON/YAML/DB serialization, or choosing between pointer and value receivers. It is also useful when the user asks about accept interfaces, return structs, compile-time interface checks, or composing small interfaces into larger ones. Overall, the Golang Structs Interfaces skill provides a set of guidelines and principles for designing effective and efficient interfaces in Go, with a focus on composition, flexibility, and clarity. By following these principles, developers can create robust and maintainable code that is easy to understand and extend.