Principal Frontend Engineer in Mundelein

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.

• Bachelor’s degree in Computer Science, Engineering, or a related field \n

• 5+ years of experience building production web applications, including senior-level ownership \n

• Prior experience operating at principal, lead, or staff engineer level \n

• Expert proficiency with TypeScript and React, including server-side rendered frameworks such as Next.js \n

• Strong understanding of functional programming concepts and immutability in modern frontend systems \n

• Advanced knowledge of automated testing strategies and CI-driven feedback loops \n

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• Own and uphold a high engineering quality bar across design reviews, code reviews, testing strategy, and production readiness \n

• Collaborate closely with product, design, and engineering partners to shape solutions and evaluate technical trade-offs \n

• Architect and build frontend-leaning, full-stack systems that are modular, composable, and resilient to change \n

• Champion performance, reliability, and maintainability in AI-assisted development environments \n

• Apply functional programming principles and immutability to reduce side effects and improve system clarity \n

• Lead the effective use of AI agents for prototyping, refactoring, and exploration while ensuring production-grade outcomes \n

• Drive a robust automated testing strategy across unit, integration, UI/component, and end-to-end layers \n

• Provide technical leadership through mentorship, delegation, and high-quality code reviews \n

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