Tettra - Tettra is a company wiki that helps teams manage and share organizational knowledge.
Apache JSPWiki - Apache JSPWiki is an open source Wiki engine, feature-rich and built around standard JEE components.
Kifi for Slack - Get links messaged on Slack in Google Search results
DokuWiki - DokuWiki is a simple to use and highly versatile Open Source wiki software that doesn't require a database.
OneBar - AI-powered Q&A knowledge base for Slack teams
MediaWiki - MediaWiki is a free software wiki package written in PHP, originally for use on Wikipedia.