A tiny, zero-dependency effect system for writing pure, testable JavaScript without mocks.

Pure Effect is a tiny, zero-dependency effect system for writing pure, testable JavaScript without mocks.

It implements the "Functional Core, Imperative Shell" pattern, allowing you to decouple your business logic from external side effects like database calls or API requests. Instead of executing side effects immediately, your functions return Commands which are executed later by an interpreter.

• Managing Side Effects: A JavaScript Effect System in 30 Lines or Less @ Lack of Imagination.

Turn screenshots into beautiful image assets. Screenshots that stick out.

Cut down on time and effort by auto-generating quality graphics from ordinary screenshots.