Add features.
Own the code.

auth

Cookie sessions with password or magic-link login. Uses Bun.password and bun:sqlite with zero npm dependencies.

bun:sqlite Bun.password hooks

images

WebP optimization middleware. Serves WebP on the fly, keeps originals untouched. No HTML changes needed.

Bun.Image middleware hooks

email

Transactional email via Resend. One function call.

resend requires RESEND_API_KEY

Write your own

An extension is a directory with a manifest, agent guidance, and source files. Publish to npm. Install with bun run shibumi add my-ext.

src/extensions/my-ext/
├── manifest.json
├── agents/
│   └── my-ext.md
└── files/