Why is lxml not written in Python?
It almost is. lxml is not written in plain Python, because it interfaces with two C libraries: libxml2 and libxslt. Accessing them at the C-level is required for performance reasons. However, to avoid writing plain C-code and caring too much about the details of built-in types and reference counting, lxml is written in Cython, a Python-like language that is translated into C-code. Chances are that if you know Python, you can write code that Cython accepts. Again, the C-ish style used in the lxml code is just for performance optimisations. If you want to contribute, don’t bother with the details, a Python implementation of your contribution is better than none. And keep in mind that lxml’s flexible API often favours an implementation of features in pure Python, without bothering with C-code at all. For example, the lxml.html package is entirely written in Python. Please contact the mailing list if you need any help.
