Builder.io
Category: AI Agents
Builder.io is a visual development platform that enables teams to build web and mobile experiences faster using AI-powered tools for product, design, and code. Builder.io was founded in 2018. The company is led by Steve Sewell. Based in San Francisco, United States. Team size: 144. Total funding raised: $37.2 million. Latest round: Series B. Key investors include Greylock, Imaginary Ventures, Microsoft's M12 Fund, LinkedIn, Bessemer Venture Partners.
- Founded
- 2018
- Headquarters
- San Francisco, United States
- Team size
- 144
- Total funding
- $37.2 million
Value proposition
AI-driven visual development platform that unifies product, design, and code, enabling non-technical users to create dynamic content while integrating with any backend or API
Products and solutions
Visual Development Platform (drag-and-drop editor + headless CMS), Fusion AI Agent (product-design-code automation), Mitosis (open-source project for component libraries), No-code/low-code integrations for Slack, Jira, Figma, and repos
Unique value
First AI agent (Fusion) that connects product, design, and code workflows, enabling bidirectional sync with tools like Figma and automated PR generation
Target customer
Businesses requiring rapid web/mobile development, including marketers, developers, and product teams; industries like e-commerce, SaaS, and enterprise applications
Industries served
E-commerce, SaaS, Enterprise Web Applications, Technology, Retail
Technology advantage
AI-powered design-to-code conversion, headless CMS flexibility, and real-time collaboration tools for developers and non-developers
How they differentiate
Builder.io differentiates through AI-powered visual development (Fusion 1.0), Mitosis open-source framework integration, and headless CMS capabilities tailored for developer workflows
Main competitors
Webflow, Contentful, Sanity, Strapi, Plasmic
Key partnerships
Microsoft (M12 venture fund investment), Integration partnerships with Figma, Slack, Jira, and major development ecosystems
Notable customers
Nike, Slack, Dropbox, Zapier, Everlane, Scale AI, JCREW, Harry's, Experian, Faire, Vistaprint, Aloyoga, ClickUp, Cathay Bank, Panasonic, Pendo, Schneider Electric, Quantcast, Afterpay, Fabletics, Vimeo
Major milestones
2021 - Launched headless CMS platform, 2022 - Reached 100+ enterprise clients, 2023 - Open-sourced Mitosis framework, 2024 - Released AI Agent Fusion 1.0, 2024 - Secured $20M in Series B funding led by M12
Growth metrics
70% YoY revenue growth, $19.4M ARR (2024)
Market positioning
Positioned as an AI-enhanced platform for enterprise-grade visual development, targeting both developers and non-technical users with drag-and-drop interfaces and code-level customization
Geographic focus
Primarily U.S.-centric with expansion into global markets, serving clients in North America, Europe, and APAC through digital delivery
Patents and IP
No public patents listed; relies on proprietary AI workflows and platform architecture
About Steve Sewell
Co-founder and CEO of Builder.io since 2018. Previously worked as Lead Web Engineer at ShopStyle, co-founded PICT (acquired by POPSUGAR), and served as Head of Product Development at Qanvis. Creator of the Mitosis open source project. Studied at University of California, Berkeley.
Official website: https://www.builder.io