Passenger
An ambient train ride you never touch — it travels its route on its own while pixel-art scenery scrolls past, changing with whatever biome the current leg passes through.
Two implementations, one shared logic
The web build came first since it's what could actually run and be checked in this environment — a zero-dependency build with no install step. The Unity/C# port is a from-scratch translation of the same route, seeded scenery, and day/night logic, targeting iOS, Android, tvOS, and console platforms from one codebase.
A deterministic, replayable world
Each leg of the route reseeds its parallax scenery deterministically, so a given leg looks consistent while it's playing but varies from one lap to the next — the same seed produces the same clouds, birds, and passing scenery every time you pass through, without ever repeating identically lap over lap.
A spec-first art pipeline
Every sprite's grid, dimensions, and frame count live in one shared spec that both a browser-based generator tool and the game's own asset loader build against — so the pipeline and the game code could go in parallel rather than the code waiting on finished art, or the art waiting on a settled engine.
Verified the way it could actually be verified
The web build was checked with automated screenshot tests rather than eyeballing it in a browser. The Unity port, with no Unity Editor available to compile it, was instead read back line-by-line against that already-verified web logic — the math is proven, whether it compiles cleanly on first import isn't yet.