We've already upstreamed a lot of changes, including one that makes all coroutines faster in Python 3.10. The big-ticket items in Cinder would be big changes for CPython and need discussion about whether CPython even wants them. You don't just slap a C++ JIT into a bugs.python.org ticket. Opening Cinder is the first step in the conversation, and we're here for that work too. It's not just "if you want it, take it."