The software is written in Haskell. I don't know much about it but it doesn't look like a bad choice. Remember that it is just a compiler / test tool, it is not

The software is written in Haskell. I don't know much about it but it doesn't look like a bad choice. Remember that it is just a compiler / test tool, it is not the embedded part, that would be the target. I don't think Rust brings much to the table here. It uses C as a back end, which is a sensible thing to do since it is the default in embedded software development, few embedded toolchains support Rust. And it is just a backend, they could have output machine code directly, but C is more universal and you can take advantage of all the C compiler optimizations. Using Rust for this would get you all of the disadvantages and none of the advantages that Rust has over C. Now, maybe you mean writing embedded code in Rust instead of C, at least, now you have a point, Rust has features that I think would be well suited for critical embedded software. But that's also what Copilot tries to do, if anything, Copilot competes against Rust (and ADA). I say that in the sense that they all address the same problem (safety) and you have to choose one solution, not that they are enemies.