facebookincubator/cinder
Cinder is Instagram's internal performance-oriented production version of CPython 3.8. It contains a number of performance optimizations, including bytecode inline caching, eager evaluation of coroutines, a method-at-a-time JIT, and an experimental bytecode compiler that uses type annotations to emit type-specialized bytecode that performs better in the JIT.
https://github.com/facebookincubator/cinder?utm_source=tldrnewsletter