Founder’s note

Hi there,

It was time to have a platform built for people shipping browser extensions.

If you have shipped an extension, you know the hard part is rarely the code. It is the path to publishing: store policies, review requirements, permission changes, and the small differences between browsers that turn releases into guesswork.

This platform is designed around that reality. Builds should be repeatable. Artifacts should be easy to inspect. Previews should be shareable. Release channels should be explicit.

This is for developers. The UI speaks in commits, artifacts, permissions, and channels. The goal is fewer surprises between Chrome, Firefox, Edge, and Safari, and more confidence when you press publish.

If something feels unclear or missing, tell me. I read every message.

CA
Cezar Augusto
Founder, Extension.js creator
hello@extension.dev

Built for developers.Ready for their agents.

Build, preview, and ship cross-browser extensions from GitHub, the console, or an agent.

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