Principal Frontend Engineer
harnhamNew York (NY)
About the role
Principal Frontend Engineer Hybrid (NYC)$150k - $200k Base + Bonus & Equity Overview The organisation builds large‑scale, consumer‑facing platforms used by hundreds of millions of users worldwide, with a strong focus on quality, long‑term maintainability, and responsible AI‑assisted development. This role sits within a financial products marketplace that partners with major financial institutions to deliver personalised consumer experiences. The position is ideal for a senior‑level engineer who values engineering judgement, thoughtful architecture, and technical leadership over speed alone.
Responsibilities:
- Own and uphold a high engineering quality bar across design reviews, code reviews, testing strategy, and production readiness
- Collaborate closely with product, design, and engineering partners to shape solutions and evaluate technical trade‑offs
- Architect and build frontend‑leaning, full‑stack systems that are modular, composable, and resilient to change
- Champion performance, reliability, and maintainability in AI‑assisted development environments
- Apply functional programming principles and immutability to reduce side effects and improve system clarity
- Lead the effective use of AI agents for prototyping, refactoring, and exploration while ensuring production‑grade outcomes
- Drive a robust automated testing strategy across unit, integration, UI/component, and end‑to‑end layers
- Provide technical leadership through mentorship, delegation, and high‑quality code reviews
- Must‑Have Qualifications
- Bachelor's degree in Computer Science, Engineering, or a related field 5+ years of experience building production web applications, including senior‑level ownership
- Prior experience operating at principal, lead, or staff engineer level
- Expert proficiency with TypeScript and React, including server‑side rendered frameworks such as Next.jsStrong understanding of functional programming concepts and immutability in modern frontend systems
- Advanced knowledge of automated testing strategies and CI‑driven feedback loops
Before you apply
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Your notice period
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