Senior Product Engineer (Frontend), Developer Products

About Kota

Kota is making insurance and retirement benefits as accessible as modern software. We do this across the Kota Platform - the world's first fully integrated benefits platform and Kota Developer Products - our embedded insurance and retirement product for platforms.

Our mission is to make insurance and benefits more accessible and delightful to this generation of employees.

Kota was started in 2022 and has raised over €20m from Europe's top technology investors, including Eurazeo, EQT Ventures, Northzone, Frontline, and angels, including Romain Huet, formerly of Stripe, now OpenAI, and David Clarke, formerly of Workday. The companies our investors have previously backed or built include Spotify, Airbnb, Klarna, Truelayer, Snapchat, Workday, Personio, Workvivo, Pointy, Workable, Wayflyer, and more.

The role

As a Senior Product Engineer (Frontend) on the Kota Developer Products team, you'll play a central role in shaping the embedded UIs, JavaScript SDKs, and user experiences that power embedded insurance and retirement benefits for platforms around the world. You'll be designing type-safe systems in a complex domain where getting it right is critical - we're building health insurance products for millions of employees across the world, creating experiences that make insurance feel simple and delightful.

You'll partner closely with designers, backend engineers, and benefit experts across Kota to turn ideas into reliable, accessible, and performant products. In this role, you'll be expected to take ownership end-to-end: from architecting multi-provider insurance flows and complex validation logic, to continuous improvement of our embedded UIs and SDK integrations.

We're looking for someone who thrives at the intersection of product thinking and engineering craft - an engineer who is as motivated by the "why" as they are by the "how," and who wants to leave a lasting impact on how benefits are delivered globally. An engineer who obsesses over type safety, accessibility, and developer experience.

We're also biased towards ambition and self-starters. We want engineers who don't wait to be told what to build - engineers who identify opportunities, propose solutions, and ship. If you're someone who leverages AI tools (Claude, Cursor, Copilot) to move faster and iterate more effectively, we want to talk.

What You'll Do

Being a part of our Developer Products team, you will be responsible to:

• Drive innovation: Build and enhance frontend products across our interconnected platforms, including JavaScript SDKs, embedded UIs, and web applications.

• Collaborate for impact: Work closely with teams across Kota to refine user experiences, ensuring excellent customer journeys and operational efficiency. Partner with backend engineers to design type-safe API contracts that enable great frontend experiences.

• Architect for the future: Research, design, and implement enhancements that strengthen our product and developer experience. Build systems that scale across numerous insurance providers without creating maintenance nightmares.

A glimpse into your week might include:

• Architecting and building complex multi-provider insurance flows with sophisticated form validation (cross-field dependencies, conditional logic based on age/provider, Zod schemas with deep refinements).

• Building embeddable SDK components with iframe management, PostMessage event systems, and theme customization for seamless third-party integration.

• Optimizing performance - implementing debouncing strategies and efficient Zod schema patterns to eliminate keystroke lag in complex forms.

• Debugging and optimizing production systems - tracing issues through 4-layer validation stacks (client, server, API, provider) using Datadog distributed tracing.

• Transforming complex insurance requirements into intuitive, accessible user experiences that make insurance feel simple.

What We're Looking For

Experience: 8+ years building modern frontend systems with expertise in:

• React + TypeScript with deep understanding of hooks, context, composition patterns, generics, conditional types, and type inference

• Complex form handling with React Hook Form (or similar), Zod validation, multi-step wizards, cross-field dependencies, and conditional business logic

• Modern frameworks - React Router 7 or Next.js experience (SSR, progressive enhancement, loaders/actions patterns)

• Type-safe API integration - contract-first development with @ts-rest, tRPC, or GraphQL with codegen

• Sophisticated state management - knowing when to use XState, React Context, URL state, server state; architecting data flows across boundaries

• Component systems - building accessible, reusable libraries with Radix UI, Tailwind CSS, design system patterns

• Testing strategies - Vitest, Playwright, Storybook for component development and visual testing

Bonus points for:

• Experience with multi-product architectures (main apps, embeddable SDKs, hosted portals)

• Monorepo experience with pnpm workspaces and Turborepo

• Building JavaScript SDKs or libraries for external developers

• Working on embedded products with iframe-based architectures, PostMessage communication, and theme overrides

• Sophisticated routing patterns with nested layouts and type-safe parameters

• Fintech, payroll, or benefits platform development (understanding regulatory constraints)

• Accessibility-first development (WCAG compliance, ARIA patterns, screen readers)

What sets you apart:

• Ambition and self-starting - you identify opportunities without being asked, propose solutions backed by technical analysis, and drive projects forward by unblocking yourself and coordinating with others

• AI-tool fluency - you use Claude, Cursor, Copilot, or ChatGPT daily to prototype, refactor, test, and debug faster; you know when to trust AI and when to verify

• Performance obsession - you optimize for speed in embedded contexts, caring deeply about TTFP and aiming for native-like performance; you measure, profile, and iterate to eliminate bottlenecks

• Systems thinking - you see patterns across different providers and build reusable abstractions; you balance type safety with pragmatism and architect for maintainability

• Product-minded engineering - you care about UX, edge cases, error messages, loading states, and accessibility; you measure impact using analytics and user feedback

• Collaborative mindset - you thrive in collaborative environments and enjoy solving complex challenges

• Cross-functional experience - you have experience collaborating directly with product teams and designers, and a proven track record of delivering value to customers or users

Availability: At least 5 hours of overlap with GMT working hours.

And of course.... Your employee benefits!

• Competitive salary and equity in a fast-growing start-up

• Health Insurance contribution via Kota

• Access to a Workplace Pension with matched contributions (depending on location)

• WFH stipend to support your home office needs

• Group Life Assurance via Kota

• Generous PTO - work hard and take the time you need

• Annual, company-wide offsite

Our Hiring Process

• Introductory Call (30 minutes): Meet one or two members of our product team to learn more about Kota and the role.

• Technical Interview (1 hour 30 minutes): A collaborative and open-book session with two of our engineers where you'll build an MVP using some of the technologies we use at Kota. Using AI tools is encouraged - we want to see how you actually work.

• Call with Founders (30 minutes): We are a small but growing team and we would want to share our vision with you and hear your thoughts.

• Final Response: We'll follow up promptly with next steps.

We are an equal-opportunity employer and value diversity at our company. We do not discriminate based on race, religion, colour, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.