Erlang is written in a ton of quite readable C and assembly. If you like delving into the internals of advanced software, it's well worth a read. Take the HiPe

Erlang is written in a ton of quite readable C and assembly. If you like delving into the internals of advanced software, it's well worth a read. Take the HiPe compiler for example: https://github.com/erlang/otp/tree/OTP-19.0/erts/emulator/hipe https://github.com/erlang/otp/tree/OTP-19.0/erts/emulator/hi... It deals with running native and interpreted program code together, just reading the comments gives you a feel for the kind of low level concepts that go into making such an interpreter. I like this one: /* * Native code calls an emulated-mode closure via a stub defined below. * * The closure is appended as the last actual parameter, and parameters * beyond the first few passed in registers are pushed onto the stack in * left-to-right order. * Hence, the location of the closure parameter only depends on the number * of parameters in registers, not the total number of parameters. */