Galaxybrain.com – a JSON-based knowledge system

In plain words

Galaxybrain.com is a JSON-based knowledge organization system that generates metadata automatically as users type and allows embedding that metadata into pages. It includes lightweight programming features like custom variables and formulas that can reference values across different pages, with updates flowing through the entire system like a spreadsheet. The tool runs on local JSON files and is free to self-host, with a hosted version planned. It's designed for people who want to build dynamic information models and interconnected knowledge systems.

written from the facts on this page · September 2026

From the sources

In the maker’s words, at launch

Hi HN, I’d like to share a project I’ve been working on called GalaxyBrain. It’s a tool for organizing information. Key features: Embeddable dynamic metadata: as you type, metadata is generated in the background. This metadata can be accessed and embedded directly into the page. Light programming concepts built in…

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