A C-based RINEX 3 reading library for Python that does not suck. Blazingly-fast, outperforming most, if not all, pure Python implementations, and even C/C++ ones (looking at you, GPSTk).
Caution: bleeding-edge, minimally working code may result in difficult to debug bugs. Not recommended (although encouraged) for production use.
What it does not do: no RINEX 2/ephemeris(SP3) support (yet). I will get to it.
Requires C compiler to be present.
python3 setup.py install
See tests.py for some examples of how to use it.