SiYuan is a privacy-first, self-hosted personal knowledge management (PKM) system built with TypeScript and Go. It targets users needing a robust, open-source solution for organizing thoughts and notes, offering fine-grained block-level referencing and a Markdown WYSIWYG editor. SiYuan provides a self-contained environment for knowledge creation and retrieval, emphasizing user data privacy and control.

How It Works

The system uses a block-centric architecture for detailed referencing and two-way linking. Its Markdown WYSIWYG editor supports complex elements like formulas and charts. Integrations include SQL query embeds, custom attributes, web clipping, PDF annotation, spaced repetition, and AI writing via OpenAI API. The project's ecosystem includes an editor engine (lute), browser extensions, a marketplace (bazaar), a data repository (dejavu), and mobile apps (Android, iOS, HarmonyOS).

Quick Start & Requirements

Installation is available via application markets, direct packages, or Docker. The b3log/siyuan Docker image supports configuration of workspace paths, user/group IDs (PUID, PGID), and access codes via environment variables or CLI arguments. Detailed Docker and Docker Compose examples are provided, covering permission management and reverse proxy setup. No specific hardware prerequisites like GPUs are mentioned.

Highlighted Details

• Fine-grained block-level referencing and two-way linking.
• Rich Markdown WYSIWYG editor with advanced charting and formula support.
• Integrated spaced repetition system for effective learning.
• AI writing and Q/A chat via OpenAI API.
• Cross-platform availability: desktop, web, Android, iOS, HarmonyOS.

Maintenance & Community

Community engagement is fostered via an English Discussion Forum, roadmap, and changelogs. Contributions are welcomed, with pointers to relevant project files.

Licensing & Compatibility

SiYuan is "fully open source," with most features free for commercial use. However, some advanced features require payment ("Member's privileges"), indicating a freemium model. The specific open-source license is not explicitly stated.

Limitations & Caveats

Exporting to PDF, HTML, or Word formats is not supported, nor is direct Markdown file import. Data synchronization via third-party sync disks is discouraged due to corruption risks; cloud storage integration is a paid feature. The README notes limitations regarding desktop and mobile application connections, suggesting primary access is browser-based, despite the mention of mobile apps.