Thanks for all of your exploration in public Simon.

Commenting because the fix I proposed was merged in roughly 49 commits after the PrismML Fork. The “tensor API is not supported” warning occurred because llama.cpp’s startup probe fails to compile a matmul2d kernel: Metal’s tensor headers require language version 4.0, but ggml-metal-device.m previously omitted MTLCompileOptions.languageVersion, disabling the API universally.

Here’s a link to the diff if you want to try and update that fork to take advantage of the prefill gains afforded by the hardware: https://github.com/ggml-org/llama.cpp/pull/27461/changes