prerex binary package in Ubuntu Focal amd64

 prerex is an editor for creating esthetically pleasing course prerequisite
 charts using the TikZ LaTeX package.
 .
 The editor supports add, remove, cut-and-paste, and edit operations on
 diagram elements, and shifts of a list of specified elements or the
 entire diagram. The edited diagram may be saved, re-processed, and viewed in
 a PDF viewer, without exiting the editor.
 .
 Course prerequisite charts allow students to easily determine which
 prerequisites, corequisites and recommended prerequisites they need for a
 given course and their time slots. Course prerequisite charts also highlight
 the courses required by a degree.
 .
 prerex is used by departments in several universities, including Queen's
 University and Suffolk University.

Source package