Eplain is a set of TeX macros that expands on and extends the definitions in plain TeX in a “style-neutral” fashion. See the Eplain manual for the rationale behind Eplain. Eplain was written by Karl Berry, Steven Smith and Oleg Katsitadze, with contributions from many others. It is mostly in the public domain, with some contributions under the GNU GPL.
The current Eplain release is version 3.9, released May 31, 2019. Older versions of Eplain are also available. The development source is available as well.
Major areas addressed by the Eplain macros include: bibliographies with BibTeX; indexing; cross-references; tables of contents; double-, triple-, quadruple-columns; hypertext links (pdfTeX, dvipdfmx and HyperTeX are supported); verbatim listings; commutative or arrow-theoretic diagrams; using (a few) LaTeX packages; and more.
The distribution comes with extensive documentation, which may be found online in HTML document and PDF.
You might find this introductory article (written for TUGboat) useful. Also, Eplain contains a set of demonstration files which illustrate various aspects of Eplain (the demo subdirectory in the distribution). The demos are thoroughly commented.
To use Eplain, all that's needed is the one command
at the top of your plain TeX document. Eplain does not work with LaTeX, except for a few packages (notably graphics, graphicx, color, url; full list).
If you have questions or comments about Eplain, or wish to participate in or keep up with Eplain development, please feel free to join the Eplain mailing list. Volunteers are always welcome.
These Eplain web pages and development are supported by the
TeX Users Group. Please consider joining TUG,
Current Eplain maintainer: Karl Berry.