effect-ts

Structure dependency injection in TypeScript using Effect layers by defining strongly-typed service interfaces with ServiceMap.Service and composing them via Layer. This approach provides modular, testable dependency management for real-world applications.

Model data and handle errors in Effect v4 by using Schema.Class for data modeling alongside branded types, and TaggedErrorClass for typed errors. This ensures type-safe data validation and explicit error management.

Test services built with Effect v4 by leveraging Layer composition to swap real implementations with test mocks. The Skill provides end-to-end testing guidance and concrete examples for running Effect-based service tests.

Yes, you can use Effect.gen and Effect.fn to structure asynchronous workflows in TypeScript. These idiomatic Effect v4 patterns allow you to write sequential-style code that handles complex concurrent operations safely.

Effect v4 works for building HTTP clients and CLI utilities by applying its modular service composition and error handling patterns. The Skill provides end-to-end guidance for integrating these utilities into TypeScript projects.