Thanks! Is this a reference to FIRRTL that I've seen some light references to (e.g. Yosys's experimental FIRRTL backend)? I was under the impression FIR was somewhat new and wasn't sure if it was used in Chisel (yet).

(To be clear, I figured you compiled to a generic IR before lowering onto some chosen HDL, regardless if it's FIR or not, but wasn't sure if Chisel had multiple HDL backends strictly speaking).