[czardoz]

> Well, the compilation step is alredy present in current py -> pyc phase

Yes, but developers don't have to ever interact with it.

> Also, look at how cython work

Cython works by adding a separate build step. Changing a Cython module requires you to recompile it, which is avoided with a JIT.

[throwaway894345]

Why would developers have to interact with a mypyc step any more than the pyc step? Why is “developers might have to interact with it” some kind of non-starter, as though having a compile phase is a worse evil than a hyper-slow language?

FWIW, I think we could probably buy ourselves a lot of latitude to optimize CPython by designating a much smaller API surface (like h.py) and then optimizations largely won’t have to worry about breaking compatibility with C-extensions (which seems to be the biggest reason CPython is unoptimized).

But in general I’ve lost faith in the maintainers’ leadership to drive through this kind of change (or similarly, to fix package management), so I’ve moved on to greener pastures (Go for the most part, with some Rust here and there) and everything is just so easy nowadays compared to my ~15 years as a Python developer.

[czardoz]

> Why is “developers might have to interact with it” some kind of non-starter, as though having a compile phase is a worse evil than a hyper-slow language?

For big monoliths (like ours at IG), the server start-up can take more than 10sec, which is already super high for a "edit -> refresh" workflow. Introducing a Cython like compilation step is really a major drawback for every single developer.

For smaller projects, Cython works extremely well (and we do use it for places where we need to interface with C/C++).

[throwaway894345]

> For big monoliths (like ours at IG), the server start-up can take more than 10sec, which is already super high for a "edit -> refresh" workflow. Introducing a Cython like compilation step is really a major drawback for every single developer.

Then skip it for your dev builds.

[czardoz]

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

[throwaway894345]

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.