TLDR; didn't work
docker run --name travis-debug -dit travisci/ci-garnet:packer-1512502276-986baf0 /sbin/init
docker exec -it travis-debug bash -l
su - travis
cd ~/builds
git clone https://github.com/travis-ci/travis-build.git
gem install travis bundler
travis version
ln -s ~/builds/travis-build ~/.travis/travis-build
bundle install --gemfile ~/.travis/travis-build/Gemfile
cd ~/builds/travis-build
bundler binstubs travis
cd ~/builds
git clone https://github.com/username/repo-name.git
cd repo-name
~/.travis/travis-build/bin/travis compile > ci.sh
bash ci.sh
There was an error in the .travis.yml file from which we could not recover.
Unfortunately, we do not know much about this error.
Please review https://docs.travis-ci.com