Comment by wyager

Yeah, sometimes I'll do e.g. a backend state management server in Haskell and then a lightweight (embedded) client in Rust. I haven't ever tried linking rust from haskell yet, if that's what you mean.

I would actually flip your HDL definition a bit. Clash is a true HDL, but specifically because it's not just a shallowly embedded DSL.

Clash is actually a GHC plugin that compiles haskell code to a synchronous circuit representation and then can spit that out as whatever HDL you like. It's emphatically not just a library for constructing circuit descriptions, like most new gateware development tools. This is possible because the semantics of Haskell are (by a mixture of good first-principles design and luck) an almost exact match for the standard four-state logic semantics of synchronous digital circuits.

This is also different from the standard HLS approach where the semantics of the source language do not at all match the semantics of the target. With Haskell, they are (surprisingly) very close! Only in a few edge cases (mostly having to do with zero-bit wires and so on) does the evaluation semantics of haskell differ from the evaluation semantics of e.g. verilog.