SynthesisUI

Desktop appAlpha 0.1.1

Watch Claude build your design system

Your page, live, while Claude works on it. One system every page follows. On your own Claude plan, in a real terminal.

Download for Windowsv0.1.1 · Nov 4, 2026 · 123 MB

Windows · Linux: .deb for Ubuntu and Debian, AppImage for the rest · macOS soon · all versions

SynthesisUI with Claude working, the page tree on the left and the page live on the right
Your Claude planClaude runs in your terminal, on your plan. The app never uses your account behind your back.
Ready in about a minuteNode, Claude Code, everything it needs - installed for you, no admin password.
Updates itselfNew versions arrive in the background. One click to restart into them.

See it happen

The page comes together while Claude builds it

Every section of your page in a tree. The one Claude is touching lights up, and the page scrolls to it.

  • Desktop, tablet and phone in one click
  • Thinking, building and review time, live
  • A check at the end of every turn
The same page at phone width, with the page tree beside it

One system

Colors, fonts and sizes that every page follows

Claude reads what you already have and turns it into your system. Every page after that is checked against it.

Your system: nine colors, two fonts and the title sizes

More hands

Several Claudes on one project

Each one in its own terminal, each one showing what it is doing. When one needs you, the question comes to you - answer with a click.

Claude 2 asking whether to keep the dark footer, with two answers to click
Undo a buildDidn't like it? Back to how the files were before that request.
Your plan limit, handledWhen you hit it, the app pauses and picks up where it stopped.
Back where you wereClose the app, open it tomorrow: your Claudes reopen in their conversations.

From download to your first page

  1. 1InstallOpen the file. It installs in seconds.no admin password
  2. 2Sign inOne click in your browser. New here? Your account is created right there.GitHub, Google or email
  3. 3Connect ClaudeThe app installs Claude Code if it is missing, and you sign in to your plan.measured: 20-35 s on Windows
  4. 4BuildPick a folder, say what you want. Watch.your first page

What's new

0.1.1 · Nov 4, 2026
  • Windows setup that does not give up. If the official Claude Code installer fails, the app installs it another way.
  • Alpha, said out loud. The app shows it is an alpha, next to its name.
0.1.0 · Nov 4, 2026
  • First release. Your page live while Claude builds it, one system every page follows, several Claudes on one project, undo, your plan limit handled, and updates in the background.
Every version on GitHub

What alpha means

This is the first release. It works, and it will have rough edges. It updates itself, so fixes arrive without a new download.

The app is not signed yet, so your computer warns you the first time you open it. That is expected. Here is how to open it anyway:

  1. 1Open the file you downloaded. Windows shows “Windows protected your PC”.
  2. 2Click More info, then Run anyway. It installs in a few seconds and opens.

What you need

A Claude planPro, Max or Team. Claude runs on your plan, in your terminal.
A SynthesisUI accountFree to start. You sign in once, inside the app.
Nothing elseNode, git and Claude Code: the app installs what is missing on its own.

Your next page, built where you can see it

Download for Windowsv0.1.1 · Nov 4, 2026 · 123 MB