Job Title
Senior UX Engineer
Salary
Not Disclosed + Equity
Company Description
StackOne is a $24M Series B startup, backed by Google Ventures and Workday Ventures, building the universal integration layer for modern SaaS products and AI agents.
Job Description
As the first dedicated UX Engineer at StackOne, you will be the internal authority on product polish and performance. You’ll own the design system, architect micro-frontends, and bridge the gap between design and engineering. Your work will directly impact how enterprise B2B customers interact with high-scale integration infrastructure and AI agentic workflows.
Location
London, UK
Why this role is remarkable
- Founding-level impact: You are the first dedicated UX hire, responsible for setting the visual language and engineering standards for the entire frontend ecosystem.
- Elite backing: Work for a high-growth Series B company backed by top-tier investors including Google Ventures (GV) and Workday Ventures.
- Scale and Innovation: Build the critical infrastructure powering integrations for global SaaS leaders like Drata, while defining how AI agents interact with user interfaces.
What You Will Do
- Own the StackOne design system by building reusable primitives and maintaining component libraries that power the entire product suite.
- Optimize frontend performance by instrumenting Core Web Vitals, managing bundle sizes, and ensuring a median Time to Interactive under two seconds.
- Collaborate with founders and product teams to prototype new features and establish AI-driven rules that maintain high UI standards across the codebase.
The ideal candidate
- Brings 4+ years of professional experience in React and TypeScript with a portfolio demonstrating exceptional visual craft and attention to detail.
- Demonstrates deep proficiency in modern CSS (Tailwind), design system architecture, and performance tuning tools like Lighthouse and bundle analysis.
- Possesses a founder's mindset with the ability to navigate Node.js backends and monorepo tooling like Nx or Turborepo to eliminate bottlenecks.
Senior UX Engineer (+ Equity) at StackOne employer: Jack & Jill
At Jack & Jill, we pride ourselves on being an exceptional employer that fosters a dynamic and innovative work culture. Our team enjoys a range of benefits including flexible working arrangements, professional development opportunities, and a collaborative environment that encourages creativity and growth. Located in a vibrant area, we offer unique advantages such as access to cutting-edge technology and the chance to work with industry leaders in AI-driven marketing strategies.
