Installing packages

Often variants will need to install additional software to satisfy build or runtime dependencies. You can have APT packages installed using the apt directives.

Background

Given examples/hello-world-c as a working directory.

Install additional build dependencies

Given this "blubber.yaml"

version: v4
variants:
  build:
    base: debian:trixie
    apt:
      packages:
        - gcc
        - libc6-dev

When you build the "build" variant

Then the image will have the following files in "/usr/bin"

gcc

Install from additional APT sources

Given this "blubber.yaml"

version: v4
variants:
  build:
    base: docker-registry.wikimedia.org/trixie:latest
    apt:
      sources:
        - url: https://apt.wikimedia.org/wikimedia
          distribution: trixie-wikimedia
          components:
            - thirdparty/otelcol-contrib
      packages:
        trixie-wikimedia: # you may use an explicit distribution/release name like so
          - otelcol-contrib

When you build the "build" variant

Then the image will have the following files in "/usr/bin"

otelcol-contrib

Provide a public key for an additional APT source

Given this "blubber.yaml"

version: v4
base: docker-registry.wikimedia.org/trixie:latest
variants:
  build:
    apt:
      sources:
        - url: https://packages.microsoft.com/debian/13/prod
          distribution: trixie
          components: [main]
          signed-by: |
            -----BEGIN PGP PUBLIC KEY BLOCK-----
            Version: BSN Pgp v1.1.0.0

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            1HwdbKTMzgF8bu1JI+tQ
            =lIzW
            -----END PGP PUBLIC KEY BLOCK-----
      packages: [dotnet-runtime-8.0]
    entrypoint: [dotnet, --list-runtimes]

When you build and run the "build" variant

Then the entrypoint will have run successfully.