Runtime
The scene APIs — authoring orchestration, frame resolution, the hosting model, effects and transitions.
Reactivity is what an actor owns. The runtime is what a scene does with those actors: records orchestration at compile time, and reconstructs state at resolution time.
Authoring and resolution
Scene orchestration
createScene, ctx.spawn, wait, all, sequence, scope — and the same surface inside actors.
Compiled scenes
Resolve frames, read typed exports, look up actors, memoize, reflect.
Determinism
What at(frame) is allowed to depend on, and what silently breaks seeking.
Structure
Structure and hosting
One hosting model: slots are positions, children are occupants.
Slots
Named hosting regions.
Children
Declared slot occupants, including owner-aware factories.