Staff Software Engineer

Senior Staff Software Engineer – Test Automation Infrastructure (ZIA Core)San Jose, California, USAZscaler accelerates digital transformation to ensure our customers can be more agile, efficient, resilient, and secure. As an AI-forward enterprise, we are constantly pushing the envelope, leveraging the world's largest security data lake to power our cloud-native Zero Trust Exchange platform. This innovation protects our customers from cyberattacks and data loss by securely connecting users, devices, and applications in any location.Here, impact in your role matters more than title and trust is built on results. We say, impact over activity. We seek innovators who actively use AI to amplify their impact and who thrive in an environment where we leverage intelligent systems to stay ahead of evolving threats. We believe in transparency and value constructive, honest debate—we're focused on getting to the best ideas, faster. We build high-performing teams that can make an impact quickly and with high quality. To do this, we are building a culture of execution centered on customer obsession, collaboration, ownership, and accountability.We value high-impact, high-accountability with a sense of urgency where you're enabled to do your best work and embrace your potential. If you're driven by purpose, thrive on solving complex challenges, and want to be part of the team that's helping to secure the AI age, we invite you to bring your talents to Zscaler and help shape the future of cybersecurity.RoleWe are looking for a Senior Staff Software Engineer – Test Automation Infrastructure (ZIA Core) to join our team. This is a hybrid (3 days per week in San Jose, CA office) role, reporting to the Sr Manager, Software Engineering, QA in the ZIA Engineering team. In this role you will own the architecture, development, and maintenance of a high-scale system test automation infrastructure for ZIA Core Datapath, a cloud security platform processing 400B+ transactions daily. You will build repeatable automation suites for L4-L7 technologies, validate cloud firewall and tunneling stacks, diagnose customer issues, and mentor engineers while driving continuous regression optimization.What You'll Do (Role Expectations)Collaborate with cross-functional teams during design, development, and maintenance of cloud-based software solutionsArchitect, design, develop, and maintain a scalable system test automation infrastructure for a cloud product processing 400B+ transactions per dayBuild repeatable automation suites to validate L4–L7 technologies, including cloud firewall, IPsec/GRE tunneling, load balancers, IPS/IDS, and routing/switchingAct as an owner and advocate for testing at scale, pushing the limits of the software under test through proficient coding methodologies and strong debugging/troubleshootingMentor and guide junior engineers, take full ownership of features, and continuously optimize the regression cycleWho You Are (Success Profile)You are a pragmatic builder obsessed with creating, iterating, and shipping, balancing technical excellence with the need to deliver value to users quickly.You act like an owner with a deep passion for the mission, operating with integrity and seamlessly navigating between high-level strategy and hands-on execution.You are driven by innovation and technical curiosity, continuously energized by solving complex challenges and finding scalable, secure solutions.You operate with urgency and a bias for action, understanding that speed and quality go hand in hand to deliver high-impact results.You are a high-trust collaborator who thrives on open feedback and clarity, driving collective success and building strong team alignment.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 domain12+ years of overall experience with strong programming skills in building test automation frameworks in PythonSolid understanding of the TCP/IP protocol stack, TLS, PKI, DNS, DHCP, VPN, HA, routing and switching, and tunneling methods such as IPsec/GREStrong background in L3, L4, and L7 filtering policies, with hands-on exposure to load balancers, IPS/IDS, and routersProven experience in manual and automated functional, integration, performance, and scale testing for cloud security/SaaS products, including test plan and test case creationExcellent debugging/troubleshooting skills to diagnose and resolve complex network infrastructure, and firewall issues in customer environmentsWhat Will Make You Stand Out (Preferred Qualifications)Experience leveraging AI-assisted coding, static/dynamic analysis, or intelligent automation tools to improve test coverage and engineering productivityHands-on experience with traffic generators, performance/load testing tools, and fuzzing techniquesTrack record of mentoring junior engineers and leading large-scale test automation or quality initiatives for distributed cloud systems