Today Groff+ms it's easy: groff -step -k file.groff > file.pdf Groff+mom it's like Texlive for TeX. The last one it's best suited for writers. With Groff+ms you can typeset equations, letters and articles with a 486 and less than 50MB of used space. It's a gem. Postscript can be set with -Tps for Groff, it may be lighter on rendering. The GV viewer opens both PDF and PS files.
A very useful feature, considering so many young kids, specially with not so doing well house income, can have Raspberry pi and produce good looking reports etc for school/ extra curricular activities, comparable to those produced by much powerful and costly hardware and software systems.
I used Groff+mom on a raspberry Pi 3b, and results were quite good for text heavy documents with some tablular data.