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Vulpes OSFirefox OS fork · Open source
Vulpes OS

Bringing Firefox OS back to life.

Vulpes adapts Gaia, the Firefox OS interface and applications, to run on a recent Gecko engine.

Free and open source, developed mainly by OverSu.

Try Vulpes View source code
The Vulpes home screen with Phone, Messages, Contacts and other Gaia apps.
The Gaia home screen on Gecko 156.0.1.

One interface for maximum compatibility

All three versions share Gaia. The engine and hardware integration are adapted to each platform.

Pixel 3aTundra · native build

Tundra boots Gecko and Gaia directly on the phone. The device page lists tested features and known limitations.

Check Pixel 3a compatibility →
AndroidPreview app

The APK lets you explore the Vulpes interface within Android. It installs like an app and does not replace your phone’s operating system.

Downloads and requirements →
DesktopDevelopment and testing

The desktop version is used to develop Gaia and test applications. Source code and setup instructions are available on Forgejo.

Open the repository →

The Vulpes architecture

On the Pixel 3a, Gaia, Gecko and Tundra make up the system. Here is what each part does.

Nivi, the Vulpes arctic fox, around a Pixel 3a.
Google Pixel 3a · Nivi

  1. GAIA

    ⌂ · HTML · CSS · JS

    Interface and applications

    The home screen, settings, dialler and other apps are written in HTML, CSS and JavaScript.

  2. GECKO

    WEB · JS · API

    Web engine

    Gecko renders the interface and runs applications. The APIs adapted for Vulpes connect them to system services.

  3. TUNDRA

    LINUX · SERVICES · HAL

    Gonk’s successor in Vulpes

    Built around the Linux kernel, Tundra boots Gecko and Gaia and provides system services and hardware access.

  4. HARDWARE

    PIXEL 3a · SARGO

    Google Pixel 3a · sargo

    The Pixel 3a is the device used for development. Its compatibility page brings together the test results.

Droidian was used for the early development tests. It is not part of Vulpes OS: Tundra has its own boot process and does not run on Droidian.

The Firefox OS fox and Nivi, the Vulpes arctic fox, side by side.
Firefox OS & Vulpes OS

What Vulpes carries over from Firefox OS

Firefox OS let developers build the phone’s interface and applications with HTML, CSS and JavaScript. That is what I want to bring back with Vulpes.

Gaia and its apps come from Firefox OS. Vulpes continues adapting them to a recent Gecko engine and replaces Gonk with Tundra for the native build. Firefox and Nivi represent that connection in this illustration.

Vulpes is an independent project, not affiliated with Mozilla.

Explore the Marketplace apps →

Follow development

I share progress, test results and unresolved issues in the changelog. You can help by testing a build, reporting a bug, translating or contributing code.

Vulpes will remain free and open source. There are no plans for subscriptions or paid features!