Position: Senior Full-Stack Engineer (VoIP Direction)
Responsibilities
- 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.
- 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.
- Performance Optimization & Quality Improvement
- Lead SDK performance profiling and optimization, including startup time, memory footprint, CPU usage, and latency;
- Optimize the entire audio/video pipelinefrom 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.
- 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- 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.
- 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.
- 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.
- 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.
