Waldo integration with CircleCI requires you only to add a couple of steps to your configuration:

jobs:
  build:
    steps:
      - run:
        name: Download Waldo CLI
        command: |
          bash -c "$(curl -fLs https://github.com/waldoapp/waldo-go-cli/raw/master/install-waldo.sh)"
        environment:
          WALDO_CLI_BIN: /usr/local/bin

      #...
      #... (generate .app)
      #...

      - run:
        name: Upload build to Waldo
        command: ${WALDO_CLI_BIN}/waldo upload "$WALDO_BUILD_PATH"
        environment:
          WALDO_CLI_BIN: /usr/local/bin
          WALDO_UPLOAD_TOKEN: <<waldoUploadToken>>
          WALDO_BUILD_PATH: /path/to/YourApp.app

Note: Make sure you use your "CI Token" (you can find it in: Sidebar > Configuration > General. We make sure tokens used in CI are only scoped to a specific app, as a result CI uploads won't work with your User token (that you can find in user menu > Account settings > Profile).