Principal Software Development Engineer - QA + Networking

Zscaler (NASDAQ: ZS) accelerates digital transformation so customers can be more agile, efficient, resilient, and secure. The Zscaler Zero Trust Exchange platform protects thousands of customers from cyberattacks and data loss by securely connecting users, devices, and applications in any location. Distributed across 200+ public data centers globally and thousands of private sites at the edge, the SASE-based Zero Trust Exchange is the world’s largest in-line cloud security platform. We believe the future of work is Human + AI and are building an AI-native enterprise where human potential is amplified by machine intelligence to solve the world’s hardest security challenges. Driven by deep customer obsession, we are committed to the mission, outcome, and to each other. We bring these commitments to life through three core behaviors: ownership and collaboration, trust through outcomes and impact, and a challenge culture with ongoing feedback. Ready to make an impact at the company pioneering security transformation in the AI era? Join us at Zscaler. Role We are looking for a Principal Software Development Engineer to join our team. This is a hybrid role based in Bangalore, India reporting to the Director Software Engineering in the Engineering department. You will join the team that built the world’s largest cloud security platform from the ground up, enabling organizations worldwide to harness speed and agility with a cloud-first strategy. With more than 100 patents and 15 million users across 185 countries, you will bring your vision to a team of experts dedicated to enhancing our multitenant architecture and global footprint. What you’ll do (Role Expectations) • Collaborate with cross-functional teams during the design phase and maintain cloud-based software solutions • Design and develop innovative test strategies to simulate complex customer usage scenarios and test at scale using Python • Develop and maintain robust, scalable test automation frameworks and integrate automated APIs into CI/CD systems (Jenkins/GitLab) • Take ownership of diagnosing and resolving customer issues, recreating production issues, and providing necessary workarounds for resolution • Provide critical insights to the development team to enhance product debugging and serviceability features Who You Are (Success Profile) • You are a problem-solver who is energized by finding solutions to complex technical challenges and delivering high-impact outcomes. • You are customer-obsessed, anchoring your decisions in solving real-world customer issues and championing their needs from start to finish. • You are a high-trust collaborator who thrives in a team environment, giving and receiving candid feedback to build trust and achieve shared goals. • You are a learner with a growth mindset, constantly developing your technical skills and actively integrating feedback to improve. • You operate with urgency and maintain a strong bias for action, delivering high-impact, high-quality results in a dynamic environment. What We’re Looking for (Minimum Qualifications) • Foundational understanding of AI/ML technologies and experience leveraging, securing, or positioning AI-driven solutions to optimize outcomes within your functional domain • Extensive experience with TCP/IP, HTTP/HTTPS/TLS, and proficient with L4-L7 protocols, certificates, and debugging network flows using tools like tcpdump and Wireshark • CCNP or equivalent knowledge and experience in the networking domain • Experience building Python-based frameworks (preferably PyTest) for API, protocol, and system tests to drive reliability and coverage across microservices and experience with testing on cloud-based architectures and working with Cloud and Kubernetes ecosystems (AWS, Docker, VM, Prox