Configures Nix on GitHub Actions for the supported platforms: Linux and macOS.
Draws heavily from Install Nix Action and is intended for use with self-hosted Github Action Runners. Once the kinks are smoothed out this should be merged into cachix/install-nix-action.
By default it has no nixpkgs configured, you have to set nix_path
by picking a channel
or pin nixpkgs yourself
(see also pinning tutorial).
- Allows specifying
$NIX_PATH
and channels vianix_path
- Enables
flakes
andnix-command
experimental features by default (to disable, setexperimental-features
viaextra_nix_config
)
Create .github/workflows/test.yml
in your repo with the following contents:
name: "Test"
on:
pull_request:
push:
jobs:
tests:
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v4
- uses: numtide/configure-nix-action@v1
with:
nix_path: nixpkgs=channel:nixos-unstable
- run: nix-build
name: "Test"
on:
pull_request:
push:
jobs:
tests:
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v4
- uses: numtide/configure-nix-action@v1
with:
github_access_token: ${{ secrets.GITHUB_TOKEN }}
- run: nix build
- run: nix flake check
To install Nix from any commit, go to the corresponding installer_test action and click on "Run numtide/configure-nix-action@XX" step and expand the first line.
-
extra_nix_config
: append to$HOME/.config/nix/nix.conf
-
github_access_token
: configure Nix to pull from GitHub using the given GitHub token. This helps work around rate limit issues. Has no effect whenaccess-tokens
is also specified inextra_nix_config
. -
nix_path
: setNIX_PATH
environment variable, for examplenixpkgs=channel:nixos-unstable
- name: Print nixpkgs version
run: nix-instantiate --eval -E '(import <nixpkgs> {}).lib.version'
With the following inputs:
- uses: numtide/configure-nix-action@vXX
with:
extra_nix_config: "system-features = nixos-test benchmark big-parallel kvm"
nix-env -i mypackage -f '<nixpkgs>'
- uses: numtide/configure-nix-action@v25
with:
extra_nix_config: |
trusted-public-keys = nix-community.cachix.org-1:mB9FSh9qf2dCimDSUo8Zy7bkq5CX+/rkCWyvRCYg3Fs= cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY=
substituters = https://nix-community.cachix.org https://cache.nixos.org/
Nix runs commands in a restricted environment by default, called pure mode
.
In pure mode, environment variables are not passed through to improve the reproducibility of the shell.
You can use the --keep / -k
flag to keep certain environment variables:
- name: Run a command with nix develop
run: nix develop --ignore-environment --keep MY_ENV_VAR --command echo $MY_ENV_VAR
env:
MY_ENV_VAR: "hello world"
Or you can disable pure mode entirely with the --impure
flag:
nix develop --impure