Docker image contains all necessary for visual testing. See example.py to know how to write basic test and bin/nosetests.sh to know how to run it.

For first time run bin/nosetests.sh example.py --with-save-baseline and create baseline. Another time run bin/nosetests.sh example.py to compare current state against baseline. Use host.local to access your localhost or take advantage of your hosts file.

For more details visit Needle, Selenium and Nose documentations.