github.com/siyuan-note/siyuan ↗

About siyuan-note/siyuan

SiYuan is a privacy-first, self-hosted personal knowledge management system built with TypeScript and Go that emphasizes local-first data storage and user control. It provides a block-level architecture for organizing and linking information, similar to tools like Obsidian and Notion, but with a focus on being fully open source and deployable on personal servers or local machines.

The application supports a comprehensive suite of features including Markdown WYSIWYG editing, two-way block references, flashcard spaced repetition, PDF annotation, web clipping, OCR capabilities via Tesseract, and integration with AI services through OpenAI and other providers. It includes native applications for desktop (via Electron), Android, iOS, and HarmonyOS, as well as Docker deployment options for server-based hosting. Users can create complex documents with mathematical formulas, charts, flowcharts, and Gantt charts, and export content to multiple formats including PDF, Word, and HTML.

SiYuan distinguishes itself through its commitment to privacy and open-source development, offering most core features free even for commercial use, with paid membership providing additional cloud synchronization and advanced features. The ecosystem includes complementary projects like the Lute editor engine, a community marketplace called Bazaar for plugins and themes, and various mobile and extension implementations. It supports synchronization through WebDAV and S3-compatible storage, and provides a comprehensive API and plugin system for extensibility.