Wiki.js

Wiki.js is a Node.js wiki with a polished admin experience, multiple editors (Markdown, WYSIWYG, and more), flexible authentication providers and a signature feature: two-way sync of content to a Git repository, so your wiki is versioned and portable.

Development of the long-promised next major version has been slow, which is worth knowing before betting a large organization on the roadmap — though the current release is stable and widely deployed with Postgres.

A good fit when Git-backed content and pluggable auth matter more than bleeding-edge collaboration features.