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# Principal Frontend Engineer in Mundelein

- **Company:** Energy Jobline
- **Location:** Mundelein, IL, United States
- **Experience:** Expert
- **Salary:** $150,000.0 - $200,000.0
- **Contract:** Permanent contract
- **Skills:** Automation of Tests, Next.js, TypeScript, Web Applications, ReactJS, Information Technology, Front End Software Development, Functional Programming
- **Published:** October 27, 2026
- **Apply:** https://www.energyjobline.com/job/principal-frontend-engineer-mundelein-32077208

## About the Role

* Bachelor's degree in Computer Science, Engineering, or a related field
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 * 5+ years of experience building production web applications, including senior-level ownership
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 * Prior experience operating at principal, lead, or staff engineer level
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 * Expert proficiency with TypeScript and React, including server-side rendered frameworks such as Next.js
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 * Strong understanding of functional programming concepts and immutability in modern frontend systems
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 * Advanced knowledge of automated testing strategies and CI-driven feedback loops
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## Description

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.