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SOC-0017: Create a Custom Desktop Environment for Linux ​

Project size: 3 months

Estimated difficulty: Hard

  • Strong Kotlin & Kotlin/Native experience (jvm, multiplatform, & cinterop)
  • Familiarity with GTK 4/Libadwaita widget APIs
  • Firm grasp of Wayland concepts, Mutter/GNOME Shell internals, and D‑Bus
  • Basic systems‑level knowledge of Linux session management (logind, xdg‑desktop‑portal)
  • Understanding of Jetpack Compose's programming model

Description ​

This project delivers a fully‑featured desktop environment written entirely in Kotlin, styled with Libadwaita, and powered by the gtk‑kn bindings.

Instead of writing a brand‑new compositor, we layer a custom shell on Mutter + Wayland — replacing GNOME Shell’s JS code with Kotlin while retaining its robust protocol stack.

Core tasks include:

  1. Session bootstrap
    Login, systemd user target, and .desktop files for X11/Wayland sessions.
  2. Reactive shell process
    Desktop window, dock, status bar, notification center, multitasking overview, and OSD overlays—built with a Compose-like declarative UI model for efficient recomposition and low-latency updates.
  3. D‑Bus / portal bridges
    Window‑manager control, media keys, battery/network indicators, and org.freedesktop.Notifications implementation.
  4. Packaging & CI
    Debian packages, GitHub/GitLab CI compiling on debian:testing, and flatpak‑friendly build scripts.

Expected Results ​

  • Working shell prototype that launches as its own session, provides window management, panels, notifications, and volume/brightness OSDs.
  • Installable .deb packages (shell binary, schemas, themes) with post‑inst scripts to register Wayland & X11 sessions.
  • Kotlin library exposing reusable widgets (Dock, TopBar, Overview) and D‑Bus helpers.
  • Full unit & integration test suite (mocked D‑Bus, window events) running in CI.
  • Comprehensive developer documentation: build instructions, architecture diagrams, code‑style guide, and contribution handbook.

Stretch Goals ​

  • Plug‑in API for third‑party Kotlin panel widgets
  • Theming engine leveraging Libadwaita CSS variables
  • Flatpak sandbox‑aware portal fallbacks
  • Accessibility support via AT‑SPI2