Some graphics libraries such as Julia's GR.jl and Python's VTK require X11 (Linux's windowing system) support files. You're might encounter the following error when running your code:
libXt.so.6: cannot open shared object file: No such file or directory .
Add the following
apt-get dependencies to your capsule (using the package management system):
For VTK, these additional dependencies might be required:
For more information on GR.jl, see this GitHub issue.