About Foldkit

Foldkit is an open source TypeScript frontend framework built on Effect. It follows The Elm Architecture: an application has one Schema-defined Model, events arrive as Messages, a pure update function moves the Model forward, and every side effect is described as data and run by the runtime.

The framework ships routing, server rendering, a headless accessible component library, two test frameworks, DevTools, and a project scaffolder. A Foldkit application is a browser single-page application, optionally prerendered or server rendered.

Foldkit is built by Devin Jameson and developed in the open at github.com/foldkit/foldkit. It is a community project, not a company product. There is no paid tier, no hosted service, and nothing to sign up for.

Everything is released under the MIT license. The published packages are foldkit, @foldkit/ui, @foldkit/devtools, @foldkit/devtools-mcp, @foldkit/vite-plugin, @foldkit/markdown, @foldkit/oxlint-plugin, and create-foldkit-app.

Every change lands through a pull request against main, with typechecking, linting, unit tests, and browser end-to-end tests running on each one. A merge that touches the site deploys straight to foldkit.dev, and only when the bundled framework sources still match their published releases. Package releases take the longer path: they publish a canary snapshot first and deploy it to canary.foldkit.dev, which runs the same smoke tests against the real deployment before anything is promoted.

Releases go out through Changesets. Every user-visible change to a published package carries a changeset that becomes its changelog entry.

Foldkit is pre-1.0. The architecture is settled and the core API is stable in practice, but minor releases can still change public surface. The roadmap lists the work that gates 1.0, which features are experimental today, and which architectural decisions will not change.

foldkit.dev is itself a Foldkit application. The documentation, the blog, the searchable API reference, and the in-browser playground all run through the same Model, update, and view that the docs describe. The source is on GitHub.

The site is also built to be read by agents. Every page is available as Markdown, the full documentation is available as one file, and a read-only JSON Content API describes the site to a program.

• Get Started creates a project and walks through the generated structure.

• Why Foldkit explains why Foldkit exists and the principles behind its design.

• Contact lists the ways to reach the project.