Can you elaborate on what you mean by "skip" Cython compilation on dev builds? How would you then test changes to Cython code?

So we weren’t talking about Cython specifically, but something Cython-like, i.e., we’re not talking about Cython’s special syntax but rather ordinary Python. This is important because it means that dev builds execute against CPython directly (i.e., your code begins executing immediately) while production builds use our hypothetical AOT compiler.