golang-structs-interfaces

Golang struct and interface design patterns — composition, embedding, type assertions, type switches, interface segregation, dependency injection via interfaces, struct field tags, and pointer vs value receivers. Use this skill 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. Also use when the user asks about "accept interfaces, return structs", compile-time interface checks, or composing small interfaces into larger ones. → See samber/cc-skills-golang@golang-naming skill for interface naming conventions (Reader, Closer, Stringer) → See samber/cc-skills-golang@golang-design-patterns skill for functional options, constructors, and builder patterns

Interfaces SHOULD have 1-3 methods. Small interfaces are easier to implement, mock, and compose. If you need a larger contract, compose it from small interfaces: // package notification — defines only what it needs The email package exports a concrete Client struct — it doesn't need to know about Sender. // Bad — zero value is broken, requires constructor | Named field | You only need the inner type internally — the outer type "has a" dependency |

Run: npx -y skills add https://github.com/samber/cc-skills-golang --skill golang-structs-interfaces --agent claude-code — the source lives at github.com/samber/cc-skills-golang.