Senior Frontend Performance Engineer – TypeScript / JavaScript / C++ / Java / C#
On site
London, United Kingdom
£ 200,000 / year
Freelance
17-03-2025
Job Specifications
Senior Frontend Performance Engineer – TypeScript / JavaScript / C++ / Java / C#
Location: London (Hybrid – 2 days WFH)
Salary: £150,000 - £200,000 (Permanent)pension, private healthcare, gym membership, 25 days + 8 BH holiday allowance, tech/hardware budget.
Join a fast-growing tech company developing cutting-edge UI solutions used at scale by some of the world's largest enterprises, financial institutions, and tech businesses. With over a million weekly downloads, this product powers real-time, high-performance applications relied upon by 90% of the Fortune 500.
They seek senior engineers who thrive on solving complex technical challenges, optimising performance, and working on large-scale data visualisation and UI frameworks.
What you'll be doing
Optimising front-end performance for real-time, data-intensive applications.
Developing and enhancing a highly optimised, scalable UI framework used by thousands of global enterprises.
Deep diving into JavaScript, TypeScript, and rendering performance to push browser limits.
Solving algorithmic and architectural challenges, ensuring the UI handles millions of data points seamlessly.
Taking complete ownership of features, from ideation to implementation, shaping a product used by millions worldwide.
What you'll bring
Deep Expertise in vanilla / pure JavaScript and TypeScript, with additional experience in C++, Java, C#, or Python.
A strong grasp of data structures, algorithms, and front-end performance optimisation.
Hands-on experience with React, Angular, or Vue, including a deep understanding of DOM rendering.
A problem-solving mindset with the ability to diagnose and fix performance bottlenecks, memory leaks, and rendering inefficiencies.
A passion for building scalable, high-performance UI components.
Why join?
Make an impact by working on a globally used product that powers some of the most demanding applications.
Tackle deep technical challenges at the intersection of front-end performance, data visualisation, and scalability.
Competitive salary of £150,000 - £200,000 plus benefits.
Engineering-first culture where your contributions truly matter.
Hybrid working with two days per week from home.
This is an opportunity to shape the future of high-performance UI. If you're ready to work on cutting-edge technology at massive scale, I'd love to hear from you.
Apply now!
About the Company
Welcome to techstack Recruitment: a digital technology recruitment business for high-growth disruptors and innovators. Our bespoke, high-end recruitment solutions empower our clients to excel in the talent acquisition battle. With our agile, consultative, white-glove approach, we set a new standard in executive search and technical talent acquisition. Through our smart, ethical, and relentless approach to finding talent, we've solved the unique hiring challenges of countless early and growth-stage companies. We are known t... Know more
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