{
  "build_from": {
    "armhf": "mycustom/base-image:latest",
    "aarch64": "mycustom/base-image",
    "amd64": "homeassistant/amd64-base-ubuntu:18.04"
  },
  "squash": false,
  "args": {
    "my_build_arg": "xy"
  }
}