New system programming language

Pyrex/Cython are indeed *fantastic*. But they don't really create the kind of system I'm talking about here, because 1) they're usually used to define little self-contained computational cores and simple wrappers around foreign code, so their interaction with overall memory management is minimal (except that they let you temporarily avoid the constant heap allocations that tend to bottleneck pure Python code), 2) they don't provide any tools beyond malloc/free anyway.