Foxden is a self-hosted Firefox Sync server for a household or small group. It replaces every Mozilla service that Sync uses with one Docker container and one SQLite database. Stock Firefox works without add-ons or custom builds.
I built Foxden for privacy, and to own all my data. Your bookmarks, history, passwords and tabs stay on a server you control, and nothing depends on Mozilla's servers.
Foxden is an independent project and isn't affiliated with or endorsed by Mozilla. Firefox is a trademark of the Mozilla Foundation.
Note: Foxden is a young project without wide testing, and its documentation is still a work in progress. Keep backups and use it at your own risk.
- Works with stock Firefox on desktop, Android and iOS.
- Keeps sync end-to-end encrypted. Firefox encrypts your data before uploading it, so the server only stores ciphertext.
- Limits accounts to people you invite, with user and admin roles.
- Provides a web app to manage your profile and signed-in devices and, for admins, everyone's accounts.
- Issues one-time password reset links for anyone who forgets their password.
- Backs up the database every night.
- Emails invite links, if you set up email.
flowchart LR
firefox[Firefox<br/>desktop, Android, iOS]
browser[Browser]
subgraph host[Server host]
proxy[Reverse proxy<br/>HTTPS]
foxden[Foxden<br/>accounts, sync, web app]
data[(SQLite and backups)]
end
firefox -->|sign-in and sync| proxy
browser -->|web app| proxy
proxy --> foxden
foxden --> data
Firefox reaches every part of Foxden on one address: the sign-in pages, the account server, the tokenserver and sync storage. Foxden stores everything in one SQLite database. Firefox encrypts sync data with a key that only your password unlocks, so Foxden can't read what it stores.
| Browser | Version |
|---|---|
| Firefox desktop (Linux) | 157.0 |
| Firefox for Android | 157.0 |
Tests sign in and sync bookmarks and history with real browsers. Firefox for iOS uses the same sign-in flow but is not covered by automated tests.
Foxden does not yet support:
- Send Tab and push notifications. Other devices pick up changes on their next scheduled sync instead.
- Pairing a device with a QR code.
- Account recovery keys. A password reset loses whatever was only stored on the server.
Foxden runs from one compose file on a machine with Docker, behind a reverse proxy that handles HTTPS. Follow the deployment guide to install it, back it up and upgrade.
Sign in to Foxden and open Getting started. It walks through pointing Firefox at your server on desktop, Android and iOS.
Foxden is developed with the help of AI. As an experienced developer, I oversee every change and review the code it produces.
See CONTRIBUTING.md. Please report security issues privately, as described in SECURITY.md.
Copyright (C) 2026 Louis Collins
Foxden is licensed under the GNU Affero General Public License v3.0 only (AGPL-3.0-only).