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Gollum
MITGollum is a Git-powered wiki replacing SaaS tools like Slab with local plain text files, version control, and multi-format markup support.
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Overview
Gollum is a lightweight Git-powered wiki engine that reads and writes markup files directly from repository history. Originally designed for GitHub's wiki system, the application requires no external database and treats directory trees of text as pages. Teams can edit documents via a local browser interface or push commits from standard desktop editors.
Why Gollum instead of Slab
Slab operates as a managed cloud knowledge base with real-time collaboration, unified search, and zero server maintenance. That convenience introduces typical SaaS trade-offs: document custody lives on third-party infrastructure, export depends on proprietary APIs, and access requires recurring subscription fees. Gollum takes the opposite operational approach by embedding documentation inside a Git repository. Running as a lightweight Ruby Rack process or Java servlet, Gollum eliminates database servers, cache clusters, and background workers. The repository filesystem acts as both document store and audit trail.
This architecture reduces disaster recovery and high availability to routine git push commands or filesystem snapshots, bypassing database migration risks during upgrades. When connectivity drops, developers continue reading and editing docs locally through terminal or offline editors. However, this minimalist model lacks Slab's live co-authoring and automatic conflict handling. Concurrent browser edits can create Git merge conflicts that require manual intervention, and multi-user access control requires an external reverse proxy or CAS authentication rather than an admin dashboard.
What it does well
- Native Git revision history: Every page edit generates a Git commit with author metadata, enabling branch workflows, diffing, and rollbacks using standard git commands.
- Multi-format markup support: Renders CommonMark, GitHub-Flavored Markdown, AsciiDoc, Org-mode, and MediaWiki through pluggable gems without file conversion.
- Zero database dependency: Operates directly on a bare or working Git repository via Rugged or JGit, removing database provisioning and schema upgrades.
- Built-in technical diagrams and math: Provides client-side rendering for Mermaid diagrams, PlantUML, and mathematical typesetting through KaTeX or MathJax.
- Bidirectional workflow integration: Allows developers to commit changes from desktop IDEs while non-technical contributors edit through the browser UI.