When comparing Xournal (Linux) vs MuPDF, the Slant community recommends MuPDF for most people. In the question“What is the best software to annotate a PDF?” MuPDF is ranked 2nd while Xournal (Linux) is ranked 7th. The most important reason people chose MuPDF is:
It was written in C and opengl, so your hardware was used fully.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Open-source and free software (GPL license)
Pro Supports Wacom tablets and similar input devices
Detects the pressure applied to the pen and adjusts the line thickness, creating more natural-looking drawings.
Pro Super fast
It was written in C and opengl, so your hardware was used fully.
Pro Vim-mode shortcut keys
Super easy to use with rapid response.
Pro Excellent for presentations
Pro Annotation capability
With mupdf-gl, you can do most of the annotations and comments.
Cons
Con Importing a PDF can be a lossy process
Upon importing some PDF files, each page becomes a raster picture. Features of the original PDF, such as vector graphics or selectible text, are completely lost.
For other PDFs, this problem does not happen.
Con No print option
Con No two page mode
Con Not enough functionality
If you want "minimal," you got it.