Claude Gave the Brainfuck Ray Tracer a 9000x Speedup

Daniel, developer of the BF-JIT brainfuck just-in-time compiler, reported that Claude Opus 5.5 optimized the 23MB brainfuck ray tracer ray.bf to roughly a 9000x speedup in 1 hour and 45 minutes, cutting a full render from months to minutes. The changes, about 1,500 extra lines of code, are published on the optimizer branch of the BF-JIT GitHub repository.

Claude gave the BrainFuck Ray Tracer a 9000x Speedup A few weeks ago someone published a blog post about a brainfuck ray tracer https://epestr.com/blog/writing-a-ray-tracer-in-brainfuck/ . The file is 23MB of brainfuck instructions and runs around 1 pixel per minute when rendering the sky, which is the fastest part of the image . That means it takes months to render the complete image. I wanted to see how my own brainfuck JIT https://github.com/danthedaniel/BF-JIT handled the problem. Unsurprisingly, it produces about 1 pixel per minute. I had been gifted “unlimited” Claude tokens for an evening for an unrelated hackathon. After I finished the main project I pointed Claude Opus 5.5 at the compiler and told it to optimize ray.bf - “no cheating ”. After 1 hour and 45 minutes Claude had the image rendering so much faster that a full image would only take minutes Here https://github.com/danthedaniel/BF-JIT/tree/optimizer is the branch with Claude’s changes. I post this not to brag about work I didn’t do. But you may find yourself in the position to loop Claude over an easily evaluated problem. Give it a shot. Given the net ~1,500 extra lines of code I think the 9000x speedup is justified. If we use these tools appropriately the future of software is bright.