aptly/server/repo/ubuntu/xenial/extra.yml

parameters:
  aptly:
    server:
      repo:
        ubuntu-xenial-extra:
          distribution: xenial
          component: main
          architectures: amd64
          comment: "Extra packages for Ubuntu Xenial"
          publisher:
            component: extra
            distributions:
              - xenial/nightly
            architectures:
              - amd64