Senior Realtime Backend Engineer

Zoom • San Jose, CA

1d • Hybrid

About The Position

You will architect high-performance C++ backend systems powering Zoom's AI-driven Contact Center platform. Working with distributed telephony infrastructure and real-time voice services, you will optimize session management and media handling at global scale. Your work will directly impact millions of customer interactions with 99.99% reliability.

We deliver cloud telephony infrastructure for Zoom's omnichannel Contact Center platform. Our team collaborates across engineering, product, and operations to build high-concurrency voice services. We exist to power seamless, AI-enhanced customer experiences at enterprise scale.

Requirements

• Communicate fluently in Mandarin to collaborate with distributed engineering teams across regions
• Demonstrate 5+ years of professional C/C++ development experience or equivalent practical experience in systems programming
• Master Linux systems programming including IPC, socket programming, I/O multiplexing (epoll), and asynchronous I/O
• Apply deep expertise in VoIP/real-time communication systems with protocols including SIP, RTP/RTCP, WebRTC, and voice codecs
• Use Redis for distributed locking, caching, and state management in high-concurrency production environments
• Contribute hands-on experience with FreeSWITCH, Asterisk, or similar telephony engines
• Apply familiarity with Lua scripting or embedded logic engines for telephony applications
• Demonstrate experience with audio quality control strategies or AI/ML integration for voice services (ASR/TTS/NLP)

Responsibilities

• Designing and optimizing distributed C++ backend modules that ensure 99.99% reliability and massive scalability for real-time voice traffic
• Developing and tuning open-source telephony engines (FreeSWITCH) for session management, media handling, and protocol compliance across global clusters
• Building low-latency synchronization mechanisms using Redis and distributed technologies to manage real-time call states with cross-functional engineering teams
• Troubleshooting complex system bottlenecks including memory leaks, thread contention, and network latency to maintain high-concurrency performance
• Collaborating with logic and product teams to optimize the C++/Lua bridge and deliver business features with minimal overhead

Benefits

• As part of our award-winning workplace culture and commitment to delivering happiness, our benefits program offers a variety of perks, benefits, and options to help employees maintain their physical, mental, emotional, and financial health; support work-life balance; and contribute to their community in meaningful ways.

What This Job Offers

• Job Type: Full-time
• Career Level: Mid Level
• Education Level: No Education Listed