Think in
full view

A mind map that never leaves your machine. The AI you already pay for edits the board with you.

Offline Bring your own AI $29.99 once

Your licence key goes here.

  • A Cygtree board titled Cardiology finals on a near-black canvas with a fine green grid: five chapters radiate from the root, each card carrying a coloured status dot, and pink brain and gavel marks sit on the chapters that hold memories and judgments. A labelled heart, the cardiac cycle against an ECG, a coronary artery drawing and a dozen rhythm strips on pink ECG paper are pinned around the branches, and a column of twelve lead-by-lead drill cards runs down the left.
    Finals revision Ninety cards, fifteen pictures, arranged by hand.
  • A Cygtree board titled Cessna 206 Preflight: nine numbered chapters run from documents through the cabin, nose, both wings and the tail to the runup, each card a single checklist line with a coloured status dot. A three-view line drawing of the aircraft, a G1000 instrument panel, a pitot-static schematic, a crosswind component chart and a centre-of-gravity envelope are pinned beside the branches they belong to.
    A preflight walkaround One checklist line per card, in walkaround order.
  • A Cygtree board titled Coding: nine chapters from complexity and data structures through sorting, trees, concurrency, git and testing to a chapter of traps, each card one line. Animated sorting diagrams, hash-table and collision schematics, a binary search tree, an abstract syntax tree and a load-factor graph sit on the canvas, alongside a video card mid-playback and a card of source code.
    Fundamentals, for an interview Sorting animations that actually run on the canvas.

Double-click a board to open it full size

Cygtree is an offline mind-mapping and whiteboard app for Windows. Boards are ordinary files on your own disk, and it costs $29.99 once.

  • Three ways to connect an AI. Claude Code, Codex and Cursor run as CLI seats inside the app; any agent speaking the Agent Client Protocol connects as an ACP seat; and a local MCP server lets any MCP client, Claude Desktop included, join the board.
  • Your AI gets 45 tools. It reads the whole tree in one call, then moves, colours, writes, connects and folds cards where they sit — and can photograph the canvas back to you.
  • Dictation that never leaves the machine. A streaming Zipformer speech-to-text model runs natively in the app. Install a language once, then no audio is ever uploaded and no API key is needed.
  • It talks back. Kokoro text-to-speech with 48 speakers across nine languages. A 349 MB one-time download, and offline from then on like everything else.
  • No telemetry. Nothing about your boards is sent anywhere. The licence check is the only thing that ever calls home.
  • Yours to arrange. Colour every card and every cable by hand, set statuses, attach memories and judgments, drop in pictures, video, PDFs and voice notes, and draw shapes straight onto the canvas.
  • No account, ever. No cloud workspace, no sign-up, no seat. Pull the network cable and the app does not notice.

The canvas

What does Cygtree's canvas offer?

A surface where nothing has to be decided in advance. Drop a card anywhere, drag it where it belongs, nest it as deep as it needs to go. There is no outline to commit to and no template to pick, so the shape of the thing shows up once the whole thing is in view.

  • Cards that nest as deep as you like, with no forced outline
  • Several roots on one board — a single file can hold three arguments
  • Text, images, video, PDFs and voice notes, all on the same card
  • Colour, status beads and collapse, so a large board stays readable
  • Boxes, arrows and outlines for anything the tree cannot say
  • Search, dictation, export and full undo
A Cygtree card titled Root 1 reading “My idea is worth it.”, with a status dot, a memory count and a brush icon along its top edge.
One card, live

Your own AI

Can an AI actually edit my mind map?

Yes — the board itself, while it is open. The agent reads the whole tree in one call, then moves, colours, writes and connects cards where they sit. Nothing is exported, pasted or re-imported, and you watch it happen.

You bring the agent you already pay for. Cygtree adds no token markup and no second AI subscription.

  • Claude Code
  • Codex
  • Cursor
  • Claude Desktop
  • Gemini CLI
  • Copilot
  • Three ways in

01 / CLI seat

Claude Code, Codex and Cursor run inside.

Point the seat at the CLI already installed on your machine. It runs in the app, beside the board, on the plan you already pay for.

02 / ACP seat

Anything that speaks ACP.

The Agent Client Protocol is the open standard Zed and JetBrains build together, and most coding agents now speak it — Gemini CLI, Copilot, Cline, Goose and more. Eleven presets fill in the details.

03 / Invite AI

Any MCP client, over a local server.

Cygtree runs an ordinary Model Context Protocol server on your own machine. Claude Desktop connects to it, and so does anything else that speaks MCP — including whatever ships next year.

Full setup, tool list and the exact address: the AI page.

Questions

Before you buy

Is Cygtree a subscription?

No. Cygtree is $29.99 once. There is no renewal, no seat fee and no plan to upgrade to.

Does Cygtree work offline?

Yes. Boards are files on your own disk and every feature except the one-time licence check runs with no network at all.

Which AI tools can edit a Cygtree board?

Three kinds, and they arrive differently. Claude Code, Codex and Cursor run as native CLI seats inside Cygtree. Any agent that speaks the Agent Client Protocol — the open Zed and JetBrains standard most coding agents now support — connects as an ACP seat. And Cygtree runs a local MCP server, so any local MCP client can join — Claude or Codex desktop, or any desktop AI with MCP tool access. Every lane gets the same 45 board tools.

Can I talk to the board instead of typing?

Yes, in both directions, and both run on your own machine. Dictation uses a streaming Zipformer speech-to-text model built into the app — install a language once, and no audio ever leaves the computer. The assistant can also read its replies aloud with Kokoro text-to-speech, 48 speakers across nine languages, which is a 349 MB download the first time. Neither is required.

Do I need to pay for AI separately?

You use the agent you already have. Cygtree sells no tokens and takes no cut of your AI spend. The board also works with the AI switched off.

What does Cygtree run on?

Windows ships today — 10 and 11, 64-bit, about an 11 MB installer. macOS and Linux are in progress and not downloadable yet. A licence is not tied to a platform, so a key bought now works on whichever build you end up running.

Can I try it before installing anything?

Yes. The browser demo is the real application with the desktop half switched off. No signup, no download.

Can I get a refund?

Buyers in the EU and UK have a statutory 14-day right of withdrawal, handled by Polar as merchant of record. The free 7-day trial exists so you can answer this before paying. Full detail on the FAQ page.

Where should we send your key?

Polar emails your licence key to this address, so it has to be one you can actually open.