nix-build

Build a nix-container and upload it to a registry.

Assumes that you have a working nix installation in your container/worker, e.g. via cachix/install-nix-action@v16. The action builds the docker image by running nix-build docker.nix (see nix's dockerTools for details, src can override this).

The resulting image is pushed to registry/path:tag, where registry must be a registry the CI has access to using the username and password input. path determines the output path, while tag can be omitted (it will be set automatically to latest for main and master, otherwise be the same as the tag or branch that is being built). The tag variable can be used to override this behavior. The version of nixpkgs used to upload the image can be set via nixpkgs.

Example

The example below uploads to the GitHub container registry (ghcr.io). You will need to create a legacy access token (ideally restricted to only uploading packages, see the official documentation for details) and set your username/token as action secrets REGISTRY_USERNAME and REGISTRY_PASSWORD, respectively.

name: Build and publish container image
on: [push]
jobs:
  build:
    name: Build and push application image
    runs-on: ubuntu-latest
    steps:
      - uses: cachix/install-nix-action@v16
        with:
          nix_path: nixpkgs=channel:nixos-22.04
      - uses: actions/checkout@v2
      - uses: 49nord/nix-container-build@v4
        with:
          registry: ghcr.io
          username: ${{ secrets.REGISTRY_USERNAME }}
          password: ${{ secrets.REGISTRY_PASSWORD }}
          path: ${{ secrets.REGISTRY_USERNAME }}/myapplication