before_install:
   - sudo apt-get update
install:
   - sudo apt-get install ghostscript
   - curl -L https://github.com/holgern/travis-texlive/releases/download/2017-09-18_02/texlive.tar.xz | tar -JxC ~
   - PATH=$HOME/texlive/bin/x86_64-linux:$PATH
script:
   - make clean
   - make BUILD_STRATEGY=latex
   - make clean
   - make