The specializer is a dedicated Mill specific library. It can be considered both the last step of compilation or the first step of execution. Since the Mill is a processor family with lots of members for different purposes and thus different parameters like belt slot count, number and kind of functional units, cache sizes etc. and the Mill heavily depends on exposing those details of the chip to the compiler for optimal static scheduling, the specializer was introduced. There is a universal, member independent kind of internal byte code software is distributed and deployed with and the specializer translates it into the actually executable binary code for the required chip. This could happen at install time or load time and also does caching and symbol resulution and similar tasks done by traditional dynamic linkers.