Fondu

Fondu is a small meta-framework for full-stack React apps, built on Hono and Vite. It runs on Bun, Cloudflare Workers and Node.

The files in app/routes/ are the URLs. A page's file holds its Hono handlers, which run on the server, and its React component, which the loader renders with props; the browser gets the component alone. Links and forms are plain <a> and <form>: Fondu's small client swaps the pages in place, with no API to write and no client-side router to keep in sync.

Quick start

bun create fondu@latest my-app   # or: npm create fondu@latest my-app · pnpm create fondu@latest my-app
cd my-app
bun dev

It asks where the app runs (Bun, Cloudflare Workers or Node; or --target bun|cloudflare|node) and whether to add code checks (oxfmt, oxlint; or --checks), and writes a small app: a route, its page, the error page, Tailwind CSS, editor snippets and an AGENTS.md for coding agents. --yes asks nothing more.

demo.fondu.dev (apps/demo) shows Fondu's features, one page each, on Cloudflare Workers with D1 and Better Auth.

Docs

fondu.dev: routes, pages and props, layouts, forms and validation, errors, type safety, server and client code, server-side rendering, static pages, MDX pages, internationalization, deploying, and the API. Every page is also Markdown for coding agents (llms.txt).

For coding agents

Fondu's rules for an app (routes, pages, forms, navigation, data, rendering, the server, types) are an agent skill, skills/fondu/, kept here with the code it describes. Install it in an app with the skills CLI:

npx skills add fondujs/fondu

An app's AGENTS.md then says only what is the app's own.

Contributing

packages/fondu          the package
packages/create-fondu   `bun create fondu`
apps/demo               Fondu's features, one page each — Workers, D1, Better Auth, coss ui
apps/site               fondu.dev: the docs, MDX and static pages on Workers
apps/conformance        fondu/client against the browsers without JavaScript (Playwright: Chromium, Firefox, WebKit)

bun install            # also builds packages/fondu (the examples use the built package, like a real app)
bun run test           # the package: a small app with app.request(), the routes, the client
bun run typecheck      # the package, the demo (with apps/demo/e2e/types.ts), the site and apps/conformance
bun run check          # format (oxfmt), lint (oxlint), typecheck
bun run dev            # rebuild packages/fondu on change

Commits follow Conventional Commits (lefthook runs commitlint, and formats and lints what is staged). A release: bun run release picks the version, tags it and pushes; CI stages it on npm (trusted publishing, with provenance), a maintainer approves it, and CI writes the GitHub Release from the commits.

apps/demo: cp .dev.vars.example .dev.vars, then bun run dev (in workerd), bun run preview, bun run deploy.

See CONTRIBUTING.md for the details, and SECURITY.md to report a vulnerability.

License

Distributed under the MIT License. See LICENSE for more information.