I suspect they are arguing that it is not because the default codegen backend produces LLVM IR, which C++ code turns into the final executable. The Cranelift ba

I suspect they are arguing that it is not because the default codegen backend produces LLVM IR, which C++ code turns into the final executable. The Cranelift backend which is pure Rust exists, but because it is not the default some people discount it. I personally believe that leveraging existing codegen infrastructure is sound engineering. Having a "pure" implementation is not a goal of the project, having solid tooling is. That might translate in the future to tackling codegen more directly, but it isn't a huge pain point today.