The usage should be as simple as:

sandbox.yml

# Docker image to run tests
image: python35


# By default, mount CWD
mount: /projects/me /test

# Optionally, define the CWD in the container
directory: /test

# Define before test
before:
  - 
  
# Shell commands to run as part of the testing pipepile
tasks:
  - make lint
  - make unit
  - make e2e

# Define after test commands to run
after:
  - echo