Extuitive, Inc Cambridge, MA Senior Frontend Developer

Overview

Extuitive is a Flagship Pioneering–backed startup reimagining product innovation for the AI era. Our mission is to empower entrepreneurs and direct-to-consumer (D2C) brands with AI-driven tools that simplify, accelerate, and scale the launch of new products. Based in Cambridge, MA, we operate like a special ops unit—fast-moving, data-driven, and relentlessly focused on impact.

Role

As a Senior Frontend Engineer, you’ll be instrumental in designing and building the end-to-end user experience of our platform. You’ll collaborate closely with product managers, designers, and backend engineers to translate complex requirements into elegant, responsive, and performant interfaces. Beyond building, you’ll set standards, mentor peers, and play a key role in scaling both our product and our engineering practices.

• Own the End-to-End Frontend - Translate designs (Figma, wireframes, product specs) into production-ready code. Build and maintain reusable components, design systems, and UI patterns for speed and consistency.
• Drive Technical Quality & Best Practices - Introduce testing frameworks (unit, integration, E2E) and enforce high code quality. Establish frontend best practices (linting, CI/CD pipelines, accessibility standards).
• Influence Architecture & Tech Choices - Make early decisions around frameworks, state management, styling systems, and frontend tooling. Advocate for the right balance of speed vs. scalability in architecture choices.
• Wear Multiple Hats - Jump in on Dev Ops, analytics, or even light backend integration when needed. Help with customer-facing issues (debugging, bug fixes, UI polish) in real time.

• 5+ years of professional front-end development experience.
• Bachelor’s degree in Computer Science, Software Engineering, or equivalent practical experience.
• Strong expertise in React
  , Next.js
  , Type Script ,
  HTML
  , and CSS (Tailwind
  
  CSS or similar).
• Experience with front-end performance optimization techniques such as lazy loading
  , code splitting
  , and caching
  .
• Advanced Figma usage (Dev Mode, Variables, Component Properties, Auto Layout, Variants) and clean handoff from prototypes to code with measurable parity.
• Mastery of adaptive layout techniques (Container Queries, CSS Grid/Flex, fluid type/spacing) across breakpoints and device classes.
• Proficiency with modern animation libraries (e.g. Framer Motion, React Spring, GSAP).
• Comfortable working in a fast-paced startup environment with evolving priorities and minimal oversight.
• Familiarity with frontend build pipelines and code hygiene best practices (e.g. linting, test coverage, pre-commit checks, etc.)
• Building and maintaining a documented component library in Storybook (or other framework).

• Exposure to AI frontend tools like AI SDK
  , Assistant UI
  , or comparable interactive agent interfaces.
• Experience with Supabase or other modern databases.
• Experience implementing async patterns in complex design systems.
• Familiarity with Google Cloud Platform (GCP), AWS and Vercel for deployment and cloud workflows.
• Experience operationalizing design tokens from Figma Variables into code (Style Dictionary/CSS variables), keeping Figma and the design system in sync.

Flagship Pioneering invents and builds platform companies, each with the potential for multiple products that transform human health, sustainability and beyond. Since its launch in 2000, Flagship has originated more than 100 companies. Many of these companies have addressed humanity’s most urgent challenges: vaccinating billions of people against COVID-19, curing intractable diseases, improving human health, preempting illness, and feeding the world by improving the resiliency and sustainability of agriculture.

Flagship has been recognized twice on FORTUNE’s “Change the World” list, an annual ranking of companies that have made a positive social and environmental impact through activities that are part of their core business strategies and has been twice named to Fast Company’s annual list of the World’s Most Innovative Companies. Learn more about Flagship at

At Flagship, we accept impossible missions to enable bigger leaps. Our core…