Ah, that is probably what is happening. I think some of the Apple includes were causing some issues for our earlier includes and so they are a bit further down in the file. It might make sense that they then hit something else that included Metal earlier. Thanks!

My concern with trying to use SPIR-V for the reflection data was that I would potentially expect the register bindings to change between the SPIR-V and the recompiled MSL code. Is it the case that I can expect the MSL generated from spirv-cross to exactly match the original SPIR-V?

Thanks for the info! I've looked through the memory management stuff and watched the talk, but it still didn't quite click. I will dig into them again though with what you've told me. I'm still slightly confused about what commandBuffer() is doing then. If I call this once a frame am I getting a new CommandBuffer object with each call and it's just that I don't need to track them because the CommandQueue will? Or am I reusing the same object again and that is safe to do after the Commit call?