From John MacFarlane, the author of Pandoc and the CommonMark spec:

Djot is a light markup syntax. It derives most of its features from commonmark, but it fixes a few things that make commonmark’s syntax complex and difficult to parse efficiently. It is also much fuller-featured than commonmark, with support for definition lists, footnotes, tables, several new kinds of inline formatting (insert, delete, highlight, superscript, subscript), math, smart punctuation, attributes that can be applied to any element, and generic containers for block-level, inline-level, and raw content.

The parser is written in Lua. Djot resolves a few ambiguities to help humans write, and makes it easier for computers to read. Looks reasonable.