As StackOne’s first dedicated UI Engineer, you will be the authority on craft, polish, and performance. You’ll own the component library, shape micro-frontend architecture, and ensure every pixel reflects best-in-class engineering. Working alongside founders from Google and Microsoft, you’ll build the infrastructure layer that enables the next generation of agentic integrations.
Senior UI Engineer at StackOne
StackOne is hiring its first dedicated Senior UI Engineer to define the visual craft and performance standards of the AI Integration Gateway. Backed by $24M from GV and Workday Ventures, this London-based team of ex-Google and Microsoft veterans is building the infrastructure layer for agentic SaaS integrations. You will own the component library, lead design system architecture, and ensure every pixel meets the highest engineering standards.
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Location
London, United Kingdom
Compensation
Not Disclosed
Company
StackOne
Role overview
SoftwareCanterbury, United KingdomSeries A (VC-backed)
StackOne is the AI Integration Gateway for SaaS products and AI Agents. With operations in the UK and US, the company enables builders of SaaS platforms and AI Agents to orchestrate hundreds of scalable, accurate, and enterprise-grade integrations. Their platform combines 25,000 pre-mapped actions on 200 connectors, an AI-powered integration development toolkit, plus security by design: a real-time architecture, managed authentication and permissions, and end-to-end observability. The company was founded by a team of former Google, Oracle, JP Morgan, Coinbase, and Microsoft employees with a mission to build the most advanced integration infrastructure for generative AI applications. StackOne has experienced rapid growth, serving enterprise clients globally, and is backed by notable investors, including GV (Google Ventures), Workday Ventures, and Episode 1.
Backed by GV (Google Ventures), Workday Ventures, XTX Ventures, Episode 1 Ventures, Playfair Capital, Founders of GitHub, Founders of Onfido, Founders of Hofy, Angel investors from OpenAI, Angel investors from Google DeepMind, Angel investors from Microsoft, Angel investors from MuleSoft.
What you will do
- Lead the development and stewardship of StackOne’s design system, establishing the visual language, reusable primitives, and performance standards for all user interfaces.
- Ship high-fidelity, pixel-perfect UIs using React and TypeScript, while managing micro-frontend patterns and optimizing Core Web Vitals to ensure industry-leading latency.
- Collaborate with product and design teams to prototype interactive proofs-of-concept, while providing internal tooling and AI rules to help other engineering teams contribute.
Who this is a fit for
- 4+ years of professional front-end engineering experience with a deep focus on visual craft, design systems, and building production-scale React applications.
- Expert-level command of TypeScript, CSS fluency (Tailwind), and modern browser APIs, with a proven track record of migrating or scaling component libraries.
- Strong performance engineering instincts, including experience with monorepo tooling like NX or Turborepo and the ability to optimize backend bottlenecks impacting the client.
Why this role is remarkable
- Join as the first dedicated UI/UX engineer, owning the entire front-end surface and setting the visual standards for a high-growth infrastructure platform.
- High-caliber environment backed by $24M from GV and Workday Ventures, founded by veterans from Google and Microsoft who value engineering taste and autonomy.
- Tackle unique performance challenges at the intersection of AI and enterprise integrations, building a system that orchestrates thousands of actions across hundreds of connectors.
How Jack & Jill work together
I get to know what you’re great at, then find roles you’d never find yourself.Ok, I'll go first. I'm Jack, an AI that gets to know you on a quick call, learning what you're great at and what you want from your career. Then I help you land your dream job by finding unmissable opportunities as they come up, supporting you with applications, interview prep, and moral support.
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