Senior Frontend Software Engineer - AI Copilot
RemoteLisbon, Lisbon, Portugal or Portugal
EXPIREDLisbon, Lisbon, Portugal or PortugalRemoteFull TimeSenior LevelLarge
Full TimeSenior LevelLarge
Job Summary
Own and deliver end-to-end product features for AI Copilot, spanning technical design, implementation, testing, and iteration. Build accessible, performant React and TypeScript interfaces using the Garden design system, partnering with design and backend teams to integrate streaming responses and handle latency. Contribute to frontend architecture decisions, improve system reliability by addressing technical debt, and mentor junior engineers through code reviews. Occasionally reach into backend APIs to unblock feature delivery.
Required Qualifications
- 5+ years of experience building and operating large-scale, Internet-facing web applications
- Strong proficiency in modern frontend development: JavaScript/TypeScript, React, and the browser platform (state management, performance, accessibility)
- Solid understanding of building against RESTful APIs and integrating with backend services; comfortable reading and making small backend changes when needed
- Experience with CI/CD practices and shipping to production frequently
- A track record of owning features end-to-end and delivering them to production with high quality
- An eye for UX and design detail — you care about how the product feels, not just whether it works
- Ability to work with uncertainty and the flexibility to pivot with changing priorities
- Comfort working in a team alongside backend, ML engineers, and scientists — you don't need to be an ML expert, but you should be curious and able to collaborate effectively across disciplines
- Strong collaboration skills and a genuine desire to help the team succeed
Desired Qualifications
- Experience building UIs on top of LLM-powered features — streaming/token rendering, chat interfaces, evaluation, or handling non-deterministic responses gracefully
- Familiarity with design systems and component libraries at scale (Garden, or equivalents)
- Working proficiency in Ruby or Python — enough to navigate our backend services and make small changes
- Exposure to containerised deployments (Docker, Kubernetes) and cloud infrastructure (AWS)
- Experience with iterative, metrics-driven product development (A/B testing, feature flags, incremental rollouts)
- Familiarity with frontend observability and performance monitoring (Core Web Vitals, error tracking)
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