Build a multi-stage Elixir project using Concourse CI

exventure-concourse.yaml

resources:
- name: ex_venture
  type: git
  source:
    uri: https://github.com/oestrich/ex_venture.git
    branch: master

- name: ex_venture-docker-image
  type: docker-image
  source:
    email: ((docker-hub-email))
    username: ((docker-hub-username))
    password: ((docker-hub-password))
    repository: ((docker-hub-username))/ex_venture

- name: elixir-docker-image
  type: docker-image
  source:
    repository: elixir
    tag: 1.7.2-alpine

- name: node-docker-image
  type: docker-image
  source:
    repository: node
    tag: 8.6

- name: alpine-docker-image
  type: docker-image
  source:
    repository: alpine
    tag: 3.8

jobs:
- name: publish-image
  public: true
  serial: true
  plan:
  - get: ex_venture
  - get: elixir-docker-image
  - get: node-docker-image
  - get: alpine-docker-image
  - put: ex_venture-docker-image
    get_params: {}
    params:
      build: ex_venture
      build_args:
        APP_VERSION: '0.24.0'
      cache_from: []
      dockerfile: 'ex_venture/Dockerfile'
      tag_as_latest: true
      target_name: builder
  # incomplete as written