RubyBoy: A Game Boy Emulator in Ruby, Now with WebAssembly!
2025-02-08
The author built a Game Boy emulator called RubyBoy in Ruby and released it as a gem. This article details the development process, covering UI implementation, ROM loading, MBC chip support, CPU and PPU implementation, and performance optimization strategies. To boost performance, the author employed YJIT, avoided unnecessary Hash creation, optimized loop calculations, and leveraged the improvements in Ruby 3.3, resulting in significant speed improvements. Ultimately, RubyBoy successfully runs in the browser thanks to WebAssembly, enabling cross-platform execution.
Development
Game Boy emulator