Builder.io Fusion
AI agent that builds apps, features and prototypes in a team's existing codebase and design system.
Overview
Fusion, now also sold as Builder Code, is an AI agent from Builder.io that builds apps, features and prototypes inside a team’s existing codebase and design system. It hands the work back as branches and pull requests and updates them from feedback.
It is built for product teams where designers, product managers and marketers work beside engineers, and targets React and component-driven JavaScript frameworks. Fusion runs in Builder’s cloud, on a local machine or in Docker containers, with a private link for systems behind a firewall.
Pricing is per user, from $24 a month, plus usage credits. Outside tools connect through MCP.
Who it is for: Product teams where designers, product managers and marketers work beside engineers.
Features
- Works inside a team's existing codebase and design system.
- Hands work back as branches and pull requests.
- Connects to GitHub repositories, Figma and design systems.
- Integrates with Slack, Jira and MCP servers.
- Uses Anthropic, OpenAI and Google models.
Details
- Website
- builder.io/fusion
- Company
- Builder.io
- Headquarters
- San Francisco, CA
- Category
- Engineering factories
- Source
- Proprietary
- Deployment
- Cloud, Local
- Topics
- Listed
- August 2026
- Last verified
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