Architecture

Flutter is not an overlay placed on top of another compositor in Denial. The engine is embedded through its native Embedder API, and the AOT-compiled Dart shell runs inside the compositor process.

The native compositor

Rust and Smithay own the state that must remain native:

• Wayland protocols and client buffers
• input devices, focus, and grabs
• output configuration
• DRM/KMS presentation
• native resource lifetimes

The Flutter shell

Flutter owns the visible desktop policy:

• shell layout and application windows
• system surfaces and settings
• motion and gestures
• interaction regions

Wayland buffers are imported as external textures into Flutter’s scene. Flutter renders the desktop into a shared GBM atlas, and each display scans out its own region through KMS.

Wayland clients ──> Rust / Smithay ──> external textures ──> Flutter scene
       input <──── native routing <──── shell hit regions <──────┘

Displays <────────────── DRM / KMS <────────────── shared GBM atlas

A versioned boundary

The native compositor and Flutter shell form a versioned bundle boundary. That keeps the responsibilities explicit and leaves room for alternative compatible shells in the future.

For implementation detail, read the architecture notes in the source repository.