chromeos-linux

ChromeOS Ash shell. On NixOS. It's bad.

This repo takes a prebuilt ChromiumOS Chrome binary, puts it in front of X11, and teaches regular Linux to answer the ChromeOS D-Bus APIs Ash expects.

The result: the Ash desktop shell — system tray, app launcher, shelf, Terminal SWA, the works — running as your Linux desktop.

How it works

Ash binary (prebuilt ChromiumOS Chrome)
    │
    └── D-Bus (system bus)
          ├── org.chromium.flimflam     ←→  [shill-bridge]      →  NetworkManager
          ├── org.chromium.cras         ←→  [cras-bridge]       →  PipeWire/PulseAudio
          ├── org.chromium.PowerManager ←→  [power-bridge]      →  UPower
          └── org.chromium.SessionManager ←→ [session-bridge]
               └── + org.chromium.UserDataAuth   (compat)

Each bridge is a small Go daemon that:

1. Owns a ChromeOS D-Bus service name on the system bus
2. Translates Ash's calls to the equivalent Linux API
3. Forwards signals back (network changes, battery level, volume)

Quick start

nix build --impure .#ash-vm            # full VM image
./result/bin/run-nixos-vm

To run as a NixOS desktop, add the module to your flake:

{
  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    ash.url = "github:vitalyavolyn/chromeos-linux";
  };
  outputs = { nixpkgs, ash, ... }: {
    nixosConfigurations.my-machine = nixpkgs.lib.nixosSystem {
      system = "x86_64-linux";
      modules = [
        ash.nixosModules.default
        ({ pkgs, ... }: {
          services.chromeos-linux = {
            enable = true;
            user = "vitalya" # replace with your username
          };
        })
      ];
    };
  };
}

What works

The desktop comes up and is usable as a very strange Linux shell:

• Ash boots into a persistent ChromeOS-style desktop with OOBE skipped.
• The shelf, launcher, quick settings, and system tray open.
• All 24 System Web Apps install, including Terminal, Files, Settings, and Camera.
• The Terminal SWA starts a real bash shell through the injected terminal UI.
• Chrome survives login/session re-execs instead of falling out of the display manager.
• The bridge daemons run for shill, CRAS, powerd, session_manager, UserDataAuth, Crostini, rmad, and Mojo service manager compatibility.
• NetworkManager feeds the shill bridge with real ethernet state.
• PipeWire/PulseAudio volume control works through the CRAS bridge.
• UPower feeds battery state into the power bridge.
• Screen brightness works through sysfs with an xrandr fallback.
• Linux desktop plumbing works: file pickers, xdg-desktop-portal-gtk, polkit prompts, and gnome-keyring.

Rough Edges

These work enough to be useful, but they are not Chromebook-grade:

What Doesn't Work Yet

• WiFi network selection, connect, and disconnect from the ChromeOS UI.
  • Actually, most settings.
• Suspend.
• Lock screen integration.
• Notifications through Ash's notification center.
• StatusNotifierItem tray icons.
• Google account login, sync, Phone Hub, Nearby Share, or other account-bound ChromeOS services.

We're ChromeOS now

CHROMEOS_RELEASE_NAME=Chrome OS in /etc/lsb-release flips Ash from built-in fallback clients to real D-Bus ones — but also enables ChromeOS Mojo IPC mode, which requires a /run/mojo/service_manager.sock peer. Our mojo-stub does the ACCEPT_INVITEE handshake and drains messages, but it's basic.

Binary patches (applied at build time)

The Chrome binary gets a few small patches:

• Terminal stub: replaces chrome.terminalPrivate.openVmshellProcess(...) with eval(localStorage.t||"") so we can inject a terminal implementation.
• CSP relaxation: 'wasm-unsafe-eval' → 'unsafe-eval' so the Terminal page can eval injected JS
• DisplayConfigurator: skip native display config on X11 (no native display delegate = crash)
• WaylandDmabufFeedbackManager: version=0 to skip dmabuf capability probing
• HasInternalDisplay: always returns true (enables brightness slider)
• OnDisconnect: no-op (prevents crash when mojo pipe times out)
• crashpad handler wrapper: always supplies --database arg (fixes a crash)

All patches fail loudly if the binary changes.

References

• ChromeOS D-Bus system_api
• Ash D-Bus client source
• chromeos-session reference