kernels/docs/locking.md

Locking kernel versions

Projects that use setuptools can lock the kernel versions that should be used. First specify the accepted versions in pyproject.toml and make sure that kernels is a build dependency:

[build-system]
requires = ["kernels", "setuptools"]
build-backend = "setuptools.build_meta"

[tool.kernels.dependencies]
"kernels-community/activation" = ">=0.0.1"

Then run kernels lock . in the project directory. This generates a kernels.lock file with the locked revisions. The locked revision will be used when loading a kernel with get_locked_kernel:

from kernels import get_locked_kernel

activation = get_locked_kernel("kernels-community/activation")

Note: the lock file is included in the package metadata, so it will only be visible to kernels after doing an (editable or regular) installation of your project.

Pre-downloading locked kernels

Locked kernels can be pre-downloaded by running kernels download . in your project directory. This will download the kernels to your local Hugging Face Hub cache.

The pre-downloaded kernels are used by the get_locked_kernel function. get_locked_kernel will download a kernel when it is not pre-downloaded. If you want kernel loading to error when a kernel is not pre-downloaded, you can use the load_kernel function instead:

from kernels import load_kernel

activation = load_kernel("kernels-community/activation")