Senior / Lead Frontend Performance Engineer

Say hello to possibilities.

Its not everyday that you consider starting a new career challenge.

RingCentral, Inc. (NYSE: RNG) is a global leader in cloud-based communications and collaboration software. We are fundamentally changing the nature of human interactiongiving people the freedom to connect powerfully and personally from anywhere, at any time, on any device. The company provides unified voice, video meetings, team messaging, digital customer engagement, and integrated contact center solutions for enterprises globally. RingCentral's open platform integrates with leading business apps and enables customers to easily customize business workflows.

Were a $2 billion company thats growing at 30+% annually and were expanding our Engineering Team to make sure we stay ahead of the competition. RingCentral is headquartered in Belmont, California, and has offices around the world.

Summary of who you are

You are not just a frontend developer who builds UI; you are a problem solver who understands what happens 'under the hood.' You know why a specific loop spikes the CPU, why a closure might retain memory indefinitely, and how the V8 engine optimizes (or de-optimizes) your code. you understand the symbiotic relationship between JavaScript code and system-level resources

Design, develop, and maintain scalable web applications and features using JavaScript, TypeScript, and Webpack

Perform in-depth triage, troubleshooting, and debugging of production and pre-production issues across web systems

Conduct detailed root cause analysis to prevent recurring issues and drive long-term stability.

Write clean, maintainable, and efficient code while following best practices in web development.

Proactively identify areas for improvement in existing systems and drive technical excellence

Required SkillSet & Experience

8-12 years of hands-on experience in web application development.

Deep JavaScript Proficiency: Mastery of ES6+ syntax not just for writing features, but for understanding how code is compiled and executed by the engine.

Knowledge of memory management strategies. Comprehensive understanding of the Event Loop, Task Queues

Proven ability to identify, isolate, and fix memory leaks

Experience in monitoring and optimizing CPU usage and System Memory (RAM) footprint to prevent browser crashes

Ability to read and interpret complex stack traces, minified code maps, and potentially browser crash dumps.

Preferred Qualifications

Experience with modern frameworks/libraries

Comfortable debugging using HAR files

Back-end experience is a bonus

Familiarity with browser internals, developer tools, and profiling techniques.

Exposure to CI/CD pipelines and automated testing frameworks.

Prior experience working in customer-facing environments or supporting production systems.

What we offer:

• Mediclaim Benefits
• Paid Holidays
• Casual/Sick Leave
• Privilege Leave
• Bereavement Leave
• Maternity Leave
• Paternity Leave
• Wellness Coaching
• Employee Referral Bonus
• Professional Development Allowances
• Night Shift Allowances

RingCentrals Engineering team works on high-complexity projects that set the standard for performance and reliability at massive scale. What kind of scale? Millions of users today and hundreds of millions tomorrow. This is your chance to help imagine, develop and deliver products that raise the technological bar, and power human connections. If youre a talented, ambitious, creative thinker, RingCentral is the perfect environment to join a world class team and bring your ideas to life.

RingCentrals work culture is the backbone of our success. And dont just take our word for it: we are recognized as a Best Place to Work by Glassdoor, the Top Work Culture by Comparably and hold local BPTW awards in every major location. Bottom line: We are committed to hiring and retaining great people because we know you power our success. RingCentral offers on-site, remote and hybrid work options optimized for the ways we work and live now.