The probabilistic programming language/statistical software Stan (website, wikipedia) receives a JAX backend, i.e. a way to emit JAX code for inference, whether as python code or jaxpr, based on a Stan model definition in the Stan programming language. This feature must be practically useable, i.e., if some features of normal Stan are not supported, these are minor and would not stop the adoption of this backend for most usecase where Stan can be used.