1UI

1UI is a local-first design canvas with chat-driven layout generation, peer-to-peer collaboration over WebRTC, code export for every frame, and a built-in MCP server that lets Claude Code and other agents edit designs.

1UI is a design canvas positioned as an AI-native alternative to Figma. Instead of bolting generation on through plugins, the canvas itself takes chat instructions: a designer describes a layout, and the tool generates, restyles or refactors it in place. Users supply their own API key, so prompts travel directly to the chosen model provider rather than through a 1UI server. The product is built around a local-first idea. Files live on the user's device by default, and the format is described as .fig-compatible, which is meant to make leaving the tool easy. Collaboration works without a central backend: one person opens a room, shares its ID, and a second person connects over WebRTC while Yjs keeps the document in sync as a CRDT. No sign-up is needed to join a room. The app runs in any modern browser, and a native Mac build made with Tauri is offered for people who prefer a desktop window. The homepage notes that the macOS build is still awaiting Apple notarization, so first launch may need a manual workaround. A second audience is developers who work with coding agents. 1UI ships a built-in MCP server exposing more than 100 design tools, grouped around reading the canvas, creating and modifying layouts, and saving or exporting results. Claude Code, Cursor and other MCP-compatible agents can therefore inspect and edit a design directly rather than only receiving a static mockup. The server supports stdio for local clients and Streamable HTTP for browser extensions and scripts, with authentication on by default and file access limited to the project root. Every frame can also be exported as framework-ready code. In the landscape of design tools, 1UI sits between mainstream cloud-based editors and code-first generators. It suits designers and design-minded developers who value privacy, offline control and agent integration over a large hosted ecosystem. Pricing is a paid subscription or a one-time lifetime purchase rather than a free tier, which should be weighed against established tools with broader plugin libraries and team features.