FourShades
Game Boy emulator · C++20 · 2026 – present
A Game Boy emulator written with AI coding agents, spec-first and test-first, and measured against the public Game Boy test ROMs. The pass rate is the scoreboard, and every number gets published — up or down.
The point is not another emulator; there are hundreds, and better ones. The point is a fixed, respected yardstick for what disciplined agentic development can actually do on hard low-level code.
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Posts about FourShades
Starting the scoreboard at zero
Why I am building a Game Boy emulator in C++ with AI agents, and publishing every number.