A hand-rolled 2D game engine, its editor, and a browser platformer built on top — all in one repo.
Bitsplash uses Bun (not npm/node). The editor runs in an Electron desktop shell and is developed on Windows.
bun install
bun run dev # launches the editor in a desktop windowThe game itself is a standalone web build — bun run build, then bun run preview to serve it in a browser.
Bitsplash is code-first and hand-rolled: no game-engine framework, a custom entity-component-system, and a physics layer behind an engine-owned abstraction (backed by Rapier), drawn to an HTML canvas via WebGL2. The codebase is split into three strict layers — a reusable engine, an editor that authors content on top of it, and the game itself — and dependencies only ever point inward; the editor and game must never leak into the engine.
The bias throughout is toward small, composable, data-driven systems (JSON scenes, data-file prefabs, metadata-in-assets), behaviour living in systems rather than object hierarchies (there is deliberately no scene graph — entities relate by id), and footgun-free APIs whose safe, fast path is the default. Everything is meant to be observable and editable from the tooling. The game ships to any modern browser; the editor is a desktop app so it can own the filesystem and reclaim browser-reserved shortcuts.
docs/EDITOR_STYLING.md— editor UI style guidedocs/plans/— detailed architectural plans per systemagents.md— codebase orientation for AI agents