The reference compiler is as free-standing as OCaml's because it too has its own back-end. Its front-end is shared with the other 2 back-ends: feeds the ubiquit

The reference compiler is as free-standing as OCaml's because it too has its own back-end. Its front-end is shared with the other 2 back-ends: feeds the ubiquitous LLVM in LDC, and is included as a supported front-end in GCC since version 9.1. Anyway, there is no way you'd give up ML-tradition pattern-matching; D doesn't have it.