{"slug": "optimizing-a-c-collision-detection-100x-with-an-llm", "title": "Optimizing a C collision detection 100x with an LLM", "summary": "A developer used an LLM to optimize a C collision detection implementation, achieving over 100x speedup from the baseline at a cost of ~125 million tokens. The optimization targeted Kevin Tracy's differentiable collision detection code for convex primitives.", "body_md": "Using an LLM to optimize code: I created a reference implementation of\n\n[@kevintracy48](https://x.com/kevintracy48)'s collision detection in C, then used gpt-5.5 to optimize it and managed a > 100x speedup from that baseline. Cost ~125M tokens Code and details:I’m excited to finally show off fast and robust differentiable collision detection between pairs of convex primitives!\npaper:\n\n[arxiv.org/abs/2207.00669](https://arxiv.org/abs/2207.00669)code:[github.com/kevin-tracy/Di…](https://github.com/kevin-tracy/DifferentiableCollisions.jl)00:00", "url": "https://wpnews.pro/news/optimizing-a-c-collision-detection-100x-with-an-llm", "canonical_source": "https://twitter.com/mike_acton/status/2066778535902298405", "published_at": "2026-06-16 19:58:26+00:00", "updated_at": "2026-06-16 20:19:09.975733+00:00", "lang": "en", "topics": ["large-language-models", "ai-tools", "developer-tools"], "entities": ["Kevin Tracy", "gpt-5.5", "DifferentiableCollisions.jl"], "alternates": {"html": "https://wpnews.pro/news/optimizing-a-c-collision-detection-100x-with-an-llm", "markdown": "https://wpnews.pro/news/optimizing-a-c-collision-detection-100x-with-an-llm.md", "text": "https://wpnews.pro/news/optimizing-a-c-collision-detection-100x-with-an-llm.txt", "jsonld": "https://wpnews.pro/news/optimizing-a-c-collision-detection-100x-with-an-llm.jsonld"}}