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SiYuan

A private, self-hosted note-taking and knowledge app with built-in AI writing and question answering.

What it does

SiYuan is a personal knowledge management app, a place to write notes and connect ideas. Every paragraph or "block" can be linked to and referenced from anywhere else, and you write in Markdown, a simple text format, while seeing the formatted result.

It focuses on privacy and can be self-hosted. It includes AI writing help and question-and-answer chat using an OpenAI-compatible service, and its makers describe it as a workspace where people and AI agents work together.

It's available as an installable app and through app stores, Docker and other hosting options. Most features are free, even for commercial use.

Who it's for

People who keep detailed notes or a personal knowledge base and want privacy and control over their data.

Can I use it without coding?

Yes. Download the installer for your computer. Self-hosting on a server needs more setup. New to this? Start here.

Can I run it?

Cost
Free, with optional paid extrasThe open-source version is free; the makers also sell a hosted or pro version.
Runs on
Windows, Phone, Server
Privacy
Your choice: run it on your device or use an online service
API key
Not needed

Try it

  1. Install SiYuan from your app store, or download it from the project's download page.
  2. Open the app and start writing and linking notes.
  3. To use the AI writing features, add an OpenAI API key in settings.
Official download page

Using Claude Code, Cursor or another AI coding assistant? Paste the prompt and it will walk you through the setup.New to this?

Before you install

  • Only download from the official GitHub page or the official download page above. Copies with similar names exist for many popular projects.
  • License (AGPL-3.0): Free to use; if you run a changed version as an online service, you must share your source code.
  • More on staying safe

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