Alchemize: PyMC’s model to replace Stan/PyMC, etc. with an LLM

This post is from Bob I’ll let Thomas Wiecki, who is one of the core PyMC devs and one of the partners at PyMC Labs, speak for himself here: Thomas Wiecki. 2026. Alchemize: Transpile PyMC to Rust for 3-7x speed-up. PyMC Discourse. If you haven’t seen what people are doing with agentic AI, this is a good example. I’m really happy that Thomas and PyMC Labs are sharing their thoughts and initial tries at things like this as I think it has the potential to benefit everyone working on modeling. If you want to see the basis of the agent’s instructions, check out the “skill” for PyMC that Chris Fonnesbeck wrote. We’ve already batted this around a bit in email with Thomas, so I can summarize some talking points: LLM-based chatbots are really good at translating. Compiling (or more technically correct, transpiling) a statistical model down to a language like Rust or C++ or JAX is a kind of translation. You can start from PyMC’s execution trace, but you can also start with a model description.…