This is an alternative server for Emacs pdf-tools.
The motivation for creating this alternative extra server, is that it lowers the barrier for adding extra features (like arrow and free text annotations) into the server. The PyMuPDF is a great and powerful library, which uses python as a wrapper language for using the Poppler library. It is still very fast as it just provides a convenient scripting language for using the underlying C code. No advanced C knowledge is required because these 'hard parts' have been taken care of by its maintainers.
Many thanks to Jorj X. McKie, for creating the PyMuPDF library and providing assistance.