nix.md

Building kernels with Nix

The kernel builder uses Nix for building kernels (the Docker image a wrapper around Nix). You can also use Nix directly if you have Nix installed on your system. The easiest way is to put a flake.nix file in the kernel directory, such as in the examples included in the examples directory:

cd examples/activation
nix build .#bundle -L

You can put this flake.nix in your own kernel's root directory to get add Nix support to your kernel.

Shell for testing a kernel

You can also start a development shell. This will give you a Python interpreter with the kernel in Python's search path. This makes it more convenient to run tests:

cd examples/activation
nix develop -L
python -m pytest tests

Building a kernel without flake.nix

If a kernels source directory does not have a flake.nix file, you can build the kernel using the buildTorchExtensionBundle function from the kernel builder itself:

cd examples/activation
nix build --impure --expr 'with import ../..; lib.x86_64-linux.buildTorchExtensionBundle ./.' -L