Senior Staff Software Development Engineer

About Zscaler Zscaler 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. Role We are looking for a Sr. Staff Engineer to join our team. This is a hybrid role based in Bangalore, reporting to the Director, Software Engineering in the Software Engineering department. In this role, you will join the Zero Trust Branch (ZTB) team, focusing on the development of high-performance, low-latency networking and security services. As part of the world’s cloud security leader, you will be at the forefront of shaping the next generation of secure networking by extending our architecture to new features and services. What you’ll do (Role Expectations) - Design and optimize system infrastructure and data paths for high-performance networking and low-latency security applications - Implement and optimize core networking protocols, including NAT, DNS, DHCP, and Policy Enforcement, to ensure enterprise-grade performance - Leverage AI coding assistants and LLMs to optimize code for performance and memory safety while streamlining the development lifecycle through automated testing - Resolve complex system issues by utilizing deep expertise in the Linux kernel, networking features, and file systems - Develop detailed technical specification documents and conduct rigorous unit tests to ensure absolute system quality and reliability Who You Are (Success Profile) - You thrive in ambiguity. You're comfortable building the path as you walk it. You thrive in a dynamic environment, seeing ambiguity not as a hindrance, but as the raw material to build something meaningful. - You act like an owner. Your passion for the mission fuels your bias for action. You operate with integrity because you genuinely care about the outcome. True ownership involves leveraging dynamic range: the ability to navigate seamlessly between high-level strategy and hands-on execution. - You are a problem-solver. You love running towards the challenges because you are laser-focused on finding the solution, knowing that solving the hard problems delivers the biggest impact. - You are a high-trust collaborator. You are ambitious for the team, not just yourself. You embrace our challenge culture by giving and receiving ongoing feedback—knowing that candor delivered with clarity and respect is the truest form of teamwork and the fastest way to earn trust. - You are a learner. You have a true growth mindset and are obsessed with your own development, actively seeking feedback to become a better partner and a stronger teammate. You love what you do and you do it with purpose. 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 - 8+ years of systems engineering experience focused on designing and optimizing infrastructure for high-performance, low-latency applications - Deep technical expertise in core networking protocols including IPsec, BGP, OSPF, and transport layer optimization (TCP/UDP) - Advanced proficiency in Linux internals, systems programming with Python or Golang, and the use of Linux kernel tools - Familiarity with agile methodologies and modern software development lifecycles in a fast-paced environment What Will Make You Stand Out (Preferred Qualifications) - Experience architecting LLM-powered agents or retrieval-augmented generation (RAG) frameworks to automate root-cause analysis for complex kernel and networking anomalies - Hands-on experience with Software Defined Networking (SDN), cloud platforms like AWS/Azure