Senior Software Engineer (Fullstack)

WHAT YOU WILL BE WORKING ON

• Building product features end-to-end in React and Next.js, with TypeScript throughout.
• Owning the data-fetching layer using TanStack Query writing clean, reusable hooks and thinking seriously about cache behaviour and invalidation.
• Managing global state with Redux where it makes sense, and pushing back when it does not.
• Writing tests at every level — unit tests for components and hooks, integration tests for data flows, and Cypress for the end-to-end journeys that must not break. We do not have a dedicated QA function. If you build it, you own making sure it works.
• Working from and contributing to specs before writing code. You should be comfortable reading a feature spec, spotting what is missing or ambiguous, and getting that resolved before you start building — not discovering it halfway through a PR.
• Collaborating with backend engineers on API contracts. If the response shape makes the frontend harder to build, you raise it before it gets built.
• On the backend side when needed: REST API changes, reading and debugging Spring Boot services, updating MongoDB queries. You will not be expected to own this, but you should be able to navigate it independently.
• Establishing frontend patterns on Project Swifty that the rest of the team can follow. How we structure components, handle errors, manage loading states.

MUST HAVE

• 5+ years of engineering experience with a clear frontend focus.
• Deep React knowledge. You understand how hooks work under the hood, not just how to use them.
• TypeScript as a first language. You lean into the type system and do not reach for 'any' when things get complicated.
• Next.js experience: routing, SSR, API routes, the works.
• Hands-on TanStack Query (or a comparable data-fetching library). You understand how caching, stale time, and invalidation actually work — not just the happy path.
• Cypress or a similar E2E tool. You know what is worth testing at that level, what belongs in a unit test, and why the distinction matters. You can look at a feature and decide what test coverage it actually needs.
• Comfortable reading and making targeted changes to backend code, even in an unfamiliar Java codebase.
• You care about the user experience — not just whether something works, but whether it feels right.

GOOD TO HAVE

• Redux Toolkit or Zustand experience beyond basic setup.
• You have worked on the frontend architecture of a new product from the beginning, not just joined an existing one.
• Exposure to performance optimisation in React — memoisation, bundle size, render behaviour.
• Some Java and Spring Boot experience beyond just reading the code.