Logseq

Logseq is a local-first knowledge base for people who work with a lot of information and can't afford to lose the thread. Your notes live as plain Markdown files on your own device, so you own them completely. No subscription required for personal use, no vendor lock-in, and no cloud dependency unless you want one.

It's built around an outliner model where every bullet is a block you can reference, embed, or query from anywhere in your notes. That structure makes it easy to build connections between ideas over time rather than hunting through disconnected documents. If you've tried tools like Obsidian or Roam Research and wanted something fully open source with strong privacy defaults, Logseq is the closest match.

Key capabilities:

• Bidirectional linking connects pages and blocks so related ideas surface automatically
• Outliner-based editing lets you nest, collapse, and reorganize thoughts at any depth
• Flashcards turn any block into a spaced-repetition card for memorizing facts
• PDF annotations keep highlights and notes alongside the source document
• Whiteboards give you an infinite canvas to arrange and connect blocks visually
• Queries let you pull structured tables of information from across your notes