This is where you would be surprised. You can prototype binary specifications with a classic computer language (like plain and simple C, I don't know how much micosoft rust support binary layout definitions and language independent core ABIs), then you can "plug" implementations in any language, the benchmark being assembly (have a look at dav1d, and probably dav2d). The only thing to keep on eye on: the runtime dependencies, for instance a generic memory allocator (usually not a good idea), and for assembly the abuse of a macro pre-processor (ffmpeg was bitten by it).