Open Source Wiki Software
A wiki lives or dies by whether anyone can find and trust a page months after someone wrote it, which makes search quality and the revision history the features that actually matter, not the editor. The open source options here keep every page as versioned text you can host yourself, with full history and diffs, so the knowledge stays searchable and accountable instead of locked inside one vendor's hosted instance.

AppFlowy
Open source AI workspace for projects, wikis, and teams with self-hosting and data control

AFFiNE
Local-first open-source workspace that merges docs, whiteboards, tables, and AI as a Notion and Miro alternative

SiYuan
Privacy-first personal knowledge management with Markdown WYSIWYG, block references, and Docker hosting

Outline
Team knowledge base and wiki with realtime collaboration, Markdown compatibility, and self-hosting documentation

Trilium Notes
Hierarchical note-taking app for large personal knowledge bases, with local use and self-hosted sync

Wiki.js
Open source wiki software with Markdown editing, Git-backed storage, and multi-provider authentication

Docmost
Open-source collaborative wiki and documentation software with real-time editing, spaces, and permissions

BookStack
Self-hosted wiki for organizing documentation and information in a simple, opinionated interface

Gollum
A Git-based wiki with local editing, version history, and support for many markup formats