For starters, python is a compiled language, it just compiles at runtime. At the same time, all you need to do to implement it evalin any compiled language is to run the compiler (and dynamically load the object code) - you can do it in Python (and in any other language) easily, because the compiler is an integral part of the runtime . Technically, nothing that stops a program written in C, calling the compiler and loading the result at runtime (using dlopen), is simply not a normal occurrence, because the C runtime does not require a compiler, so most users do not.