SiYuan

Open SourceAGPL-3.0Self-hostable

The block-based personal knowledge base with WYSIWYG editing, bidirectional links and built-in spaced-repetition flashcards — local-first, self-hostable, yours.

Open source alternative to

Notion

Visit SiYuan View source

About SiYuan

SiYuan is the power-user's personal knowledge base: block-level editing like Notion, bidirectional links like Roam, and spaced-repetition flashcards built in — so the notes you take actually get remembered.

Everything is local-first. Your notes live on your machine, sync is optional and end-to-end encrypted, and you can self-host the whole thing with Docker. Attribute queries, SQL-style database views and a plugin marketplace make it one of the deepest PKM tools anywhere.

AGPL-3.0 licensed with a large international community, SiYuan suits serious note-takers who want Notion-grade structure without giving up ownership.

Key features

Block-based WYSIWYG — Notion-style blocks with instant rendering — drag, nest, embed and query them.
Backlinks & graph — Bidirectional links, block references and a graph view connect your thinking.
Built-in flashcards — Turn any block into a spaced-repetition card — review without leaving your notes.
Local-first, encrypted sync — Notes stay on your device; optional sync is end-to-end encrypted, or self-host with Docker.

The honest read

What we like

Deep feature set: blocks, backlinks, queries, flashcards
Local-first with E2E-encrypted optional sync
Self-hostable and AGPL-licensed
Plugin marketplace and themes
Strong performance on large vaults

Worth knowing

Denser learning curve than simpler note apps
UI is busier than minimalist rivals
Some sync features are paid
Collaboration isn't the focus

FAQ

Is SiYuan free?

Yes — SiYuan is free and open source under AGPL-3.0. The optional official cloud sync is paid, but self-hosting sync is free.

How is SiYuan different from Notion?

SiYuan is local-first and self-hostable with your notes stored on your device, and it adds backlinks and built-in flashcards. Notion is cloud-only and closed-source.

Does SiYuan have spaced repetition?

Yes — any block can become a flashcard reviewed on a spaced-repetition schedule, similar to Anki, without leaving the app.

Can I self-host SiYuan?

Yes — a Docker image lets you run SiYuan on your own server, including sync.

Does SiYuan work offline?

Fully — it's local-first, so everything works offline; sync happens when you're back online.