I would like to contribute mandoc. Also present in Debian, Fedora, 
Ubuntu, ... and as the default man page formatter on *BSD.

Useful to check man pages for compatibility with *BSD systems.

The build is reproducible without the need to export SOURCE_DATE_EPOCH.

SUMMARY="BSD mandoc compiler toolset"

DESCRIPTION="\
mandoc is a suite of tools compiling mdoc, the roff macro language of
choice for BSD manual pages, and man, the predominant historical language
for UNIX manuals.  It is small, self-contained, and quite fast.  The main
component of the toolset is the mandoc utility program, based on the
libmandoc validating compiler, to format output for UTF-8 and ASCII
terminals, HTML 5, PostScript, and PDF."

mandoc-1.14.6-1.tar.xz:
usr/bin/demandoc.exe
usr/bin/mandoc.exe
usr/bin/mapropos -> mandoc
usr/bin/mman -> mandoc
usr/bin/msoelim.exe
usr/bin/mwhatis -> mandoc
usr/sbin/mandocdb -> ../bin/mandoc
usr/share/doc/mandoc/*
usr/share/man/man1/demandoc.1.gz
usr/share/man/man1/mandoc.1.gz
usr/share/man/man1/mapropos.1.gz
usr/share/man/man1/mman.1.gz
usr/share/man/man1/msoelim.1.gz
usr/share/man/man1/mwhatis.1.gz
usr/share/man/man5/mandoc.conf.5.gz
usr/share/man/man5/mandoc.db.5.gz
usr/share/man/man7/mandoc_char.7.gz
usr/share/man/man7/mandoc_eqn.7.gz
usr/share/man/man7/mandoc_man.7.gz
usr/share/man/man7/mandoc_mdoc.7.gz
usr/share/man/man7/mandoc_roff.7.gz
usr/share/man/man7/mandoc_tbl.7.gz
usr/share/man/man8/mandocdb.8.gz

-- 
Regards,
Christian