[monocasa]

It is scala. Chisel is just a scala framework. Conceptually it's not quite an HDL but instead a scala program that metaprograms the actual RTL netlist. So there's no chisel compiler other than the standard scala one that comes with sbt; you then run the resulting chisel program on your computer to generate the netlist.

[georgelyon]

This is not strictly true anymore as the low-level (FIRRTL) compilation is powered by CIRCT (http://GitHub.com/llvm/circt) which is built using MLIR (part of the LLVM project: https://GitHub.com/llvm/llvm-project)

[phendrenad2]

It's scala + a DSL called "chisel" that you write by chaining scala keywords and symbols in the right order.

There, solved it once and for all. :)