Foldkit is a frontend framework built on Effect, architected like Elm, and written in TypeScript, providing a complete architecture for predictable state management.
It uses a single immutable model, explicit effects as values, and scales linearly with complexity, making it suitable for complex state like auth flows or real-time data.
Includes batteries: type-safe routing, accessible UI components, submodels, subscriptions, managed resources, field validation, testing primitives (Story and Scene), and DevTools with time-travel and AI agent integration via MCP.
Designed for Effect developers, teams valuing correctness, and projects with complex state; not suitable for incremental adoption in large React codebases or teams unwilling to invest in Effect.
Foldkit is client-side only, prescribes architecture instead of leaving it to the developer, and is optimized for AI-generated code and human review.