[dagw]

IronPython also wasn't compatible with any python library that used the C API. Essentially we're back to the point that removing the GIL is 'easy' as long as you don't care about backwards compatibility.

[dekhn]

in many ways ironpython obviated the C API. It had a different approach to extension, based on CLR and .NET. Even the containers used .NET data types.

[dagw]

Oh absolutely, but that did make IronPython more of a separate language that shared syntax with cpython rather than a drop in replacement for cpython.