[pabloem]

From FAQ[1]:

> IronPython is an implementation of Python that is implemented using .NET. While IronPython tries to be usable from within .NET, Pyjion does not have a compatibility story with .NET. This also means IronPython cannot use C extension modules while Pyjion can.

[1] https://github.com/tonybaloney/pyjion#ironpython

[qalmakka]

So it basically uses .NET in place of something like, LLVM, in order to generate native code. Clever.