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Comment by gyrovagueGeist | Hacker News Reader

You will ~likely get some improvement by directly putting your python code in a .pyx file and compiling it (without using any cdef functions). In most cases it will be as if you were calling the Python C API directly in a compiled C file. In my experience, the biggest difference will be a reduction in the function call overhead so it is better for tight loops.

I wouldn't expect a full 2x in every case. But it can also be very significant in cases where Cython deduces the type of local variables.

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Cython 3 also uses python type annotaions to infer C types now too, so if you add python types you might see surprising cython speedups.

Coming back to this thread, I am running one now. It's too early to say if there's a speedup.

But I want to note it is ridiculously under-documented how to make what I would call a functional a.out from this toolset.

You basically are assumed to run python3 >>> import 'mything' and then run mything.main(args) instead of getting a functional commandline tool which "just runs" -the stepover is small, true, but I would have thought the PRIMARY use case here is commandline executable, not "embed .so in my interpreter"

There are a tonne of stack overflow "how do I" and all of them are really whacked: everyone trips over the same problems of :main undefined and a swag of other problems trying to call (g)cc themselves.

I guess it’s mismatched expectations. IMO the primary use-case is making python wrappers for C/C++ code or converting prototype Python code into a fast C extension for production use by adding types or progressively converting code into a language that is a mix of Python and C.

That's fair. Many happy customers so it's very likely I misunderstood the mission and vision.

My primary experience in Python3 is to minimise REPL and get to commands which do stdin -> <process it> -> stdout and gang them up, or uplift discrete commands into yield() pipes inside the same interpreter.

I guess I fell into the trap of going from the particular to the general.

It’s designed for building libraries really. You write functions in the foo.pyx file, Cython generates a foo.c file which gets compiled to foo.cpython-39m-x86_64-linux-gnu and then in your script you do “import foo”

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