»You would expect a whole lot of organizations and people to fancy a language that's about as high-level as Python, yet almost as fast and down-to-the-metal as C.

Add to that the ability to seamlessly integrate with both your existing C/++ codebase and your Python codebase, easily mix very high level abstractions with very low-level machine access... clear winner.« → Dun Peal on c.l.py

»A general rule of thumb is that your program spends 80% of its time running 20% of the code. Thus a good strategy for efficient coding is to write everything, profile your code, and optimize the parts that need it. Python’s profilers are great, and Cython allows you to do the latter step with minimal effort.« → Hoyt Koepke

»The biggest surprise (and of course this is Cython's selling point) is how simple the interfacing between high level and low level code becomes, and the fact that it is all very robust.

It's exiciting to see that there are several active projects around that attempt to speed up Python. The nice thing about Cython is that it doesn't give you "half the speed of C" or "maybe nearly the speed of C, 3 years from now" -- it gives the real deal, -O3 C, and it works right now.« → Fredrik Johansson

»Basically, Cython is about 7x times faster than Boost.Python, which astonished me.« → Chris Chou

»I'm honestly never going back to writing C again. Cython gives me all the expressiveness of Python combined with all the performance and close-to-the-metal-godlike-powers of C. I've been using it to implement high-performance graph traversal and routing algorithms and to interface with C/C++ libraries, and it's been an absolute amazing productivity boost.« → Andrew Tipton

»Using Cython allows you to just put effort into speeding up the parts of code you need to work on, and to do so without having to change very much. This is vastly different from ditching all the code and reimplementing it another language. It also requires you to learn a pretty minimal amount of stuff. You also get to keep the niceness of the Python syntax which may Python coders have come to appreciate.« → Craig Macomber

»If you have a piece of Python that you need to run fast, then I would recommend you used Cython immediately. This means that I can exploit the beauty of Python and the speed of C together, and that’s a match made in heaven.« → Stavros

»From 85 seconds (at the beginning of this post) down to 0.8 seconds: a reduction by a factor of 100 ...thank you cython! :-)« → André Roberge

»Writing a full-on CPython module from scratch would probably offer better performance than Cython if you know the quirks and are disciplined. But to someone who doesn't already drip CPython C modules, Cython is a godsend.

Ultimately, there's 5 commonly used ways (CPython [C-API], Boost::Python, SWIG, Cython, ctypes) to integrate C into Python, and right now you'd be crazy not to give Cython a shot, if that's your need. It's very easy to learn for anyone familiar with both C and Python.« → ashika

»What I loved about the Cython code is that I use a Python list to manage the Vortex objects. This shows that we can use the normal Python containers to manage objects. This is extremely convenient. [...]

Clearly, if you are building code from scratch and need speed, Cython is an excellent option. For this I really must congratulate the Cython and Pyrex developers.« → Prabhu Ramachandran

»I wrote a script that compute a distance matrix (O^2) in Python with Numpy arrays and the same script in Cython. It took me 10 minutes to figure it out how Cython works and I gained a speed up of 550 times !!! Amazing« → kfrancoi

»I would like to report on a successful Cython project. Successful in the sense that it was much faster than all code written by my predecessors mainly because the speed scales almost linearly with the number of cores. Also, the code is shorter and much easier to read and maintain. [...]

Making it this fast & short & readable & maintainable would have been pretty hard without Cython.« → Alex van Houten

»At work, we’ve started using Cython with excellent success. We rewrote one particular Perl script as Cython and achieved a 600% speed improvement. As a Perl lover, this was impressive. We still get all the benefits of Python such as rapid development and clean object-oriented design patterns but with the speed of C.« → Wim Kerkhoff

»The reason that I was interested in Cython was the long calculation times I encountered while doing a multi-variable optimization with a function evaluation that involved solving a differential equation with scipy.integrate.odeint. By simply replacing the class that contained the differential equation with a Cython version the calculation time dropped by a factor 5. Not bad for half a Sunday afternoons work.« → Korbinin

»I was surprised how simple it was to get it working both under Windows and Linux. I did not have to mess with make files or configure the compiles. Cython integrated well with NumPy and SciPy. This expands the programming tasks you can do with Python substantially.« → Sami Badawi

»This is why the Scipy folks keep harping about Cython – it’s rapidly becoming (or has already become) the lingua franca of exposing legacy libraries to Python. Their user base has tons of legacy code or external libraries that they need to interface, and most of the reason Python has had such a great adoption curve in that space is because Numpy has made the data portion of that interface easy. Cython makes the code portion quite painless, as well.« → Peter Z. Wang

»Added an optional step of compiling fastavro with Cython. Just doing that, with no Cython specific code reduced the time of processing 10K records from 2.9sec to 1.7sec. Not bad for that little work.« → Miki Tebeka

»... the binding needed to be rewritten, mainly because the current binding is directly written in C++ and is a maintenance nightmare. This new binding is written in Cython« → Bastien Léonard