ludic/docs/language/phases/phase-start.md

id	name	category	kind	tokens	sig	tip	order
phase-start	Start	phases	phase	Start	phase Start	Runs once at boot, before the game loop — the place to set up initial state.	0

Start is the boot phase: a handler … phase Start runs exactly once, before the first frame and before the per-frame loop begins. Use it to build the world that everything else assumes — seed the RNG with Random.seed, set the tilemap size with Map.size, spawn the starting models, and initialise your program vars. It runs before any scene is entered, so it is the one phase a scene layer handler may not use; per-scene setup belongs in a scene's on enter block instead. Every other phase (Input, FixedUpdate, Update, LateUpdate, Render) then repeats each frame, but Start never runs again.

program StartExample {
  property Position { column: int = 0, row: int = 0 }
  model Player { Position }

  const GRID_WIDTH: int = 20
  state StartExampleState {
    score: int = 0
  }

  handler SetUpWorld(start_example_st: mut StartExampleState) phase Start {
    Random.seed(value: 1)
    Map.size(width: GRID_WIDTH, height: 15)
    start_example_st.score = 0
    spawn Player { Position { column: 10, row: 7 } }
  }

  handler DrawWorld(start_example_st: StartExampleState) phase Render {
    Screen.clear(Color.MidnightBlue)
    Screen.draw_number(x: 4, y: 4, value: start_example_st.score, color: Color.Gold, scale: 1)
    Screen.show()
  }
}