Service Implementation Skill

Design and implement Effect services as focused capabilities that compose into complete solutions.

Effect Source Reference

The Effect v4 source is vendored in consuming projects at repos/effect/. Browse and read files there directly to look up APIs, types, and implementations.

Reference this for:

• Context source: packages/effect/src/Context.ts
• Layer source: packages/effect/src/Layer.ts
• Migration guide: MIGRATION.md
• Effect source: packages/effect/src/

Service Declaration: Namespace-Module Pattern

The recommended pattern organizes each service as a TypeScript namespace containing: an Interface type, a Service class (pure tag/identifier), and layer / defaultLayer exports. The class body is always empty — construction logic lives in Layer.effect, not in make: or class statics.