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Comment by jgalvez | Hacker News Reader

Is it just me or this does sound like an extremely elegant stack in the making? No VMs, just plain native Unix-speaking software.

Prediction: lots of emerging startups who are basing their code on Python today are going to resort to this (or PyPy, but that's unrelated) when the scaling pain begins, or simply to attempt making things run a bit faster. I think this is great. Most people I know avoid C completely because of the hidden pitfalls every novice has to go through, but maybe Cython will slowly change that. It just needs a bit more maturity and some endorsements to pop up around here... which shouldn't take too long.

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We have already done this but wrote plain C extensions. Actually C libraries with a clean interface, then wrapped them in Python extensions as well.

With C and Python you get to play on both ends of the spectrum -- concise clear code, and high performance code with C.

Pure C extensions will give you the best performance. If you write really modular C code, interop with it and Python is really clean.

Cython is interesting, but as cited, there are also some limitations and caveats. See http://docs.cython.org/src/userguide/limitations.html and http://docs.cython.org/src/tutorial/caveats.html

Cython is not a bad story for C interop, though. See e.g. pyevent (http://code.google.com/p/pyevent/), which provides Python bindings to libevent. Be warned: until there's a new release of pyevent (0.4), you should, in my opinion, use the SVN version.

I very much agree with this. Especially if you use similar C library interfacing styles, you can reuse or abstract out the glue parts easily.

About playing on both sides of the efficiency/expressiveness spectrum, the important thing is to be sure to do real benchmarks so you only drop down into C when it pays off.

Sometimes, the reasons are not just efficiency -- you may already have C code that does the right thing.

The only problem is that, for the vast majority of companies, CPU time isn't the major bottleneck. I don't think there are many companies who do so advanced algorithmic stuff that it takes hours to complete them, unless you're doing some ML (or other) processing in the background.

In that case, however, you should very definitely (as in, I'm not even considering an alternative) go with Python/Cython, as you will develop many times faster and your program will have near-C speed.

My current favorite is ShedSkin, which compiles your (unmodified) program written in a subset of Python (not a particularly limiting subset, mind you) into C++ which you can then compile (and link as a module, if you like).

My experiences with both:

http://www.korokithakis.net/node/117

http://www.korokithakis.net/node/109

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