> It's also questionable how well performance relevant platform specifics survive all these layers.

Fair point, but one of Rust's strengths is the many zero-cost abstractions it provides. And the article talks about how the code complies to the GPU-specific machine code or IR. Ultimately the efficiency and optimization abilities of that compiler is going to determine how well your code runs, just like any other compilation process.

This project doesn't even add that much. In "traditional" GPU code, you're still going to have:

1. Domain specific GPU code in whatever high-level language you've chosen to work in for the target you want to support. (Or more than one, if you need it, which isn't fun.)

...

3. Compiler that compiles your GPU code into whatever machine code or IR the GPU expects.

4. Vulkan, OpenGL, DX12 and Metal...

5. Drivers...

6. Hardware...

So yes, there's an extra layer here. But I think many developers will gladly take on that trade off for the ability to target so many software and hardware combinations in one codebase/binary. And hopefully as they polish the project, debugging issues will become more straightforward.