Felix is a programming language with a fully featured purely functional subsystem embedded in a a traditional Algol-like imperative programming system. The system features garbage collection, static typing, parametric polymorphism, overloading, regular expression matching, and a lot more. A scripting harness is used to invoke source files, but fully compiled binary shared libraries are generated, yielding both rapid prototyping and high performance. Seamless binding of C/C++ code makes interfacing existing libraries easy. Control inversion provides language-level cooperative multi-tasking.