Position: Senior Full-Stack Engineer (VoIP Direction)

Responsibilities

1. VoIP SDK Architecture & Evolution
   • Lead the end-to-end architecture design of a multi-platform (iOS / Android / Web / Desktop) VoIP SDK;
   • Design and optimize core modules including signaling, media engine abstraction, transport, and encryption;
   • Build a unified cross-platform SDK interface and modular framework for long-term scalability and maintainability.
2. Feature Implementation & Delivery
   • Translate complex product requirements into robust, high-performance real-time communication solutions;
   • Deliver consistent functionality and user experience across different platforms;
   • Collaborate closely with backend, product, and QA teams to ensure high-quality, on-schedule releases.
3. Performance Optimization & Quality Improvement
   • Lead SDK performance profiling and optimization, including startup time, memory footprint, CPU usage, and latency;
   • Optimize the entire audio/video pipeline—from capture, encode, transport, decode, to render;
   • Monitor and improve key QoE metrics (latency, jitter, packet loss, freeze ratio, MOS, etc.);
   • Design and maintain an intelligent monitoring and auto-tuning system for call quality.
4. AI-Driven Development & Innovation
   • Explore and apply AI-assisted programming methodologies (e.g., code generation, model-assisted debugging, AI agent collaboration);
   • Integrate AI capabilities into real-time communication workflows such as quality assessment, network scheduling, and media enhancement;
   • Build an AI-powered self-optimization and diagnostics framework within the SDK.

Qualifications

1. Background
   • Bachelor’s degree or higher in Computer Science, Telecommunications, or related fields;
   • 5+ years of full-stack or client-side development experience, including 3+ years in VoIP / Real-Time Communication systems.
2. Technical Skills
   • Proficient in one or more of the following: Objective-C, Swift, Java, Kotlin, C++;
   • Strong understanding of WebRTC, QUIC, SRTP, RTP and related real-time transport protocols;
   • Familiar with FEC (Forward Error Correction), NACK, PLC, JitterBuffer and other packet-loss recovery or error-resilience mechanisms;
   • Deep understanding of audio/video capture, codec integration, synchronization, QoS, and adaptive bitrate control;
   • Experienced in modular SDK design, performance tuning, and cross-platform development.
3. Preferred Qualifications
   • Hands-on experience leading or contributing to cross-platform VoIP SDK architecture (iOS / Android / Web / Desktop);
   • Familiar with AI-assisted development tools (e.g., GitHub Copilot, Cursor, Claude, or LLM APIs);
   • Experience with AI-powered media enhancement (AEC, ANS, super-resolution, noise suppression, dynamic rate control);
   • Strong system design mindset, abstraction ability, and architectural vision.
4. Personal Attributes
   • Flexible and proactive, comfortable working across multiple platforms and languages;
   • Strong ownership, engineering discipline, and curiosity for deep system optimization;
   • Excellent communication skills and cross-functional collaboration ability;
   • Passionate about building world-class real-time communication experiences.