.travis.yml

language: python            # this works for Linux but is an error on macOS or Windows
matrix:
  include:
    - name: "Python on Linux"
      python: 3.7           # this works for Linux but is ignored on macOS or Windows
      python: 3.8           
      python: 3.6
      python: 3.5
    - name: "Python 3.7 on macOS"
      os: osx
      osx_image: xcode11    # Python 3.7.2 running on macOS 10.14.3
      language: shell       # 'language: python' is an error on Travis CI macOS
      # python: 3.7         # 'python:' is ignored on Travis CI macOS
      before_install: python3 --version ; pip3 --version ; sw_vers
    - name: "Python 3.7 on Windows"
      os: windows           # Windows 10.0.17134 N/A Build 17134
      language: shell       # 'language: python' is an error on Travis CI Windows
      # python: 3.7         # 'python:' is ignored on Travis CI Windows
      env:  PATH=/c/Python37:/c/Python37/Scripts:$PATH
      before_install:
        - choco install python  --version 3.7 # this install takes at least 1 min 30 sec
        - python --version
        - python -m pip install --upgrade pip

install:
  - ./.travis/install.sh

script:
  - bash -c echo "Tests must go here" # pytest

before_deploy:
  - ./.travis/build_binaries.sh

deploy:
  provider: releases
  api_key: $RELEASE_TOKEN
  file_glob: true
  file: 
    - dist/kb_*
  skip_cleanup: true
  on:
    tags: true
  name: $TRAVIS_TAG