Compose for a New Surface

Build a custom Compose toolkit

Eleven visual lessons connect the Compose boundary to a reusable surface contract, retained tree, host, renderer, interaction model, and library boundary.

Chapter 01

Lessons

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01

Build a custom Compose toolkit

Eleven visual lessons connect the Compose boundary to a reusable surface contract, retained tree, host, renderer, interaction model, and library boundary.

  1. Find the Compose boundarySeparate the machinery supplied by Compose from the UI policy that a new surface requires.3 min →
  2. Create a multiplatform foundationPlace the reusable toolkit engine in Kotlin Multiplatform `commonMain` and keep platform integration behind narrow contracts.3 min →
  3. Define the Surface contractCreate the smallest boundary through which a complete logical frame can reach any surface.3 min →
  4. Build a retained node treeDefine the objects that survive recomposition and carry UI intent into layout and rendering.4 min →
  5. Teach Compose with an ApplierImplement the structural bridge through which Compose Runtime maintains the Atlas node tree.3 min →
  6. Emit nodes from composablesDefine a Compose target and connect declarative Atlas components to retained Atlas nodes.3 min →
  7. Host composition and framesUnderstand the process owner that coordinates composition, snapshot notifications, frame time, rendering, and cleanup.4 min →
  8. Understand state and identityTrace a state mutation into an in-place node update and predict when identity is retained, moved, or replaced.4 min →
  9. Add layout and renderingTurn retained intent into geometry and then into a complete `SurfaceFrame` that is not mutated after construction.5 min →
  10. Add events, focus, and semanticsReturn typed interaction from the surface to component state without coupling components to a platform protocol.6 min →
  11. Package and verify the toolkitTurn the learning implementation into a reusable library with explicit public boundaries and layered evidence.6 min →