What happens when you launch the app
First-time visitors land inside a live demo so you can feel the product before committing a folder. Edits in a demo disappear on refresh. When you're ready, pick an empty folder — GalaxyBrain can clone the current demo into it, or just open the folder as a blank workspace. Returning visits re-open your most recent folder automatically.
Your folder is your workspace
Pick a folder, and that folder is your workspace. One folder, one user, no account. GalaxyBrain writes plain .jsonl files into pages/ and templates/, and saves pasted images into images/. You can zip the folder, back it up, or hand it to a friend. It's all just files on your disk.
Works in Chrome, Edge, and Brave on desktop. From the workspace menu you can also save an offline build — a single standalone HTML file that runs from file:// with no network.
Pages, blocks, items
A page has an icon, a title, a subtitle, and a body made of blocks — think of them as sections. Each block can freely mix prose, headings, bullets, checkboxes, ordered lists, embedded images, variables, and page links. You might have a Summary block, a Todos block, and a Projects block on the same page.
Moving around
The workspace is tab-based: every open page is its own resizable column, side by side. Click an inline link or a page-link item and the current tab navigates to it, dropping a breadcrumb trail so you can walk back up. Cmd-click (Ctrl on Windows) opens links in a new tab. Cmd-K opens workspace-wide search across every page title, real or template.
The /, @, and $ menus
Three keystrokes drive most of the structured editing:
/— insert a dynamic value. A word count, a created-at timestamp, another page's variable, an aggregation across linked pages.@— insert an inline page link. The link renders with the target's current title, so renames propagate automatically across every reference.$— inside templates only, insert a placeholder:$NextNumber,$NextDay,$DateToday.
Starting a line with a common prefix converts it as you type. # becomes a heading, - or * a bullet, 1. an ordered-list item, [] an unchecked checkbox, [x] a checked one, >name a variable. Paste a URL and it becomes a link automatically.
Variables and live values
A variable is a named cell with a formula. Formulas support arithmetic, constants, functions like sqrt, round, and log, and references to other variables or dynamic values. Results update automatically whenever the data they depend on changes.
Variables compose across pages. A "Projects" page can sum the cost variable across every linked project page without the project pages knowing anything about the overview.
Page links, collections, and backlinks
Inline links sit inside prose — "I spoke to [Jane Doe] about [Portfolio Website]." Page-link items take up their own line and show the target page's icon, title, and subtitle — used when the link is the content: a row in a Projects list, a daily entry in a Journal index.
Any block of page-link items can be auto-sorted — by title, by created or updated time, by a metric (word count, list items, reference count, checkbox totals), or by any named variable on the linked pages. Inserting a new link drops it into the right slot; updating the sort key re-sorts the whole block.
Every real page shows its linked references at the bottom — every other page in the workspace that mentions it, grouped by source.
Templates
Templates are blueprint pages with the full editing feature set, plus three placeholders that resolve when a real page is created from them: $NextNumber, $NextDay, $DateToday. A "Journal Entry" template numbers each entry automatically. A "Meeting" template stamps today's date.
Creating from a template clones the blueprint, resolves the placeholders, and links the new page into the block you launched from. "Create another" repeats it without re-picking.
AI agents
Point an MCP-aware tool (Claude Code, Claude Desktop, Cursor, Codex) at your workspace and it can read, search, traverse, and edit pages — through GalaxyBrain, under the same rules the editor enforces. Agents can't corrupt a workspace any more than you can.
Setup takes a few lines in your MCP config. Full install steps and the 12 tools are on the MCP docs page. Scripts and CLIs can talk to the same local server directly over the WebSocket API.
Questions? Email hello@galaxybrain.com.