Most of nodejs internals are in C++ on top of libuv. Only a thin layer of JS interfaces wrap that.
Python is also a dynamic, GCed language. uvloop is built with Cython, which uses the Python object model (and all of its overhead!), and CPython C-API extensively (so it's slower than a pure C program using libuv).
Python is also a dynamic, GCed language. uvloop is built with Cython, which uses the Python object model (and all of its overhead!), and CPython C-API extensively (so it's slower than a pure C program using libuv).