Open Source Internal Knowledge Base Projects
Platforms for building internal wikis, documentation hubs, and knowledge bases for teams and organizations.

Apache Answer
Open-source Q&A platform for communities, help centers, and internal team knowledge bases, with voting, reputation, and a plugin system.
Alternative to:
Stack Overflow
Stack Overflow
Docmost
Open-source collaborative wiki and documentation platform, an alternative to Confluence and Notion.
Alternative to:
Confluence
Confluence
Wiki.js
Wiki.js is a modern, powerful open-source wiki app built on Node.js. Versioned, searchable, beautiful, and self-hosted — a knowledge base for any team, big or small.
Alternative to:
Notion