Senior Sustaining Software Engineer

Job Summary

We are looking for a Senior SD-WAN Sustaining Engineer to develop, troubleshoot, and debug software for an SD-WAN appliance/platform. The role focuses primarily on production support, sustaining engineering, complex defect resolution, and product reliability rather than new feature development. The ideal candidate should have strong C/C++, Linux, networking, and SD-WAN experience, with excellent debugging and root-cause analysis skills.

Key Responsibilities

Investigate and resolve complex production and customer issues in SD-WAN software. Perform root-cause analysis across datapath, routing, packet processing, session management, and system components. Develop, test, and deliver high-quality fixes for supported releases. Debug issues related to performance, scale, HA, configuration, networking, and hardware/OS interactions.

Work closely with Engineering, QA, Product Management, and Release Engineering teams. Improve product reliability, supportability, logging, diagnostics, and troubleshooting capabilities. Develop unit, integration, functional, and regression tests to prevent recurring issues. Participate in code reviews with focus on performance, compatibility, concurrency, security, and regression risks.

Analyze recurring defects and field issues and drive long-term corrective actions. Support release readiness, maintenance releases, defect reviews, and technical documentation. Clearly document root cause, resolution, testing, and customer/product impact.

Required Skills

6-10 years of software engineering experience , preferably in networking, security, distributed systems, or telecom products. Strong C and/or C++ programming experience. Strong Linux systems and debugging skills. Good understanding of IPv4/IPv6, TCP/UDP, routing, forwarding, tunneling, NAT, QoS, and packet flows . Hands-on experience with SD-WAN, routers, firewalls, network operating systems, or networking products .

Experience with GDB, packet capture tools (Wireshark/tcpdump), logs, tracing, and performance analysis tools . Strong experience in troubleshooting production, intermittent, performance, scale, and environment-specific issues . Ability to trace issues across control plane, management plane, and datapath . Experience with Git/source control, code reviews, CI/CD, defect tracking, and regression testing.

Strong analytical, problem-solving, communication, and ownership skills. Bachelor's or Master's degree in Computer Science, Computer Engineering, Electrical Engineering, or equivalent practical experience. Good to Have Experience developing or sustaining SD-WAN appliances . Experience with networking/security products or carrier-grade systems.

Knowledge of high availability, packet processing, performance optimization, and system-level troubleshooting. Experience working on maintained release branches and backporting production fixes