Nix Development¶

OpenMed includes a Nix flake for a pinned package build and a reproducible development shell. This is an additional build path for NixOS and nix-darwin users; the existing uv and pip workflows remain supported.

Enter the development shell¶

Install Nix with flakes enabled, clone the repository, and run:

nix develop

The shell provides Python 3.12, OpenMed, the tools and Python packages from the dev extra, and the test-only PyArrow dependency used by the collected suite. Optional ML and platform extras such as MLX and Core ML are not part of the Nix shell.

Run the same test command used by the repository gate:

python -m pytest tests/ -q

For a single non-interactive command, use:

nix develop --command python -m pytest tests/ -q

Build the package¶

Build the default OpenMed package with:

nix build

The result symlink points to the package in the Nix store. The package uses buildPythonPackage with Hatchling and contains the openmed command and Python package.

Validate and update the pin¶

Run the flake checks before submitting a Nix-related change:

nix flake check --print-build-logs

This builds both the OpenMed package and development shell. CI also runs the complete test suite inside that shell on Linux.

flake.lock records the exact nixpkgs 26.05 revision and content hash. Update that pin only as an intentional dependency-maintenance change, then validate and commit both lock and flake files together:

nix flake update
nix flake check --print-build-logs
nix develop --command python -m pytest tests/ -q