Principal Software Development Engineer (Backend Dev - C/Linux/GDB)

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, reporting to the Senior Manager, Software Development Engineering in the Data Protection department. In this position, you will serve as a premier technical leader, defining architectural direction, designing high-performance systems-level subsystems, and driving the engineering execution of our next-generation inspection capabilities. What you’ll do (Role Expectations) • Architect and implement high-performance DLP engines, dictionary compilers, and distributed incident processing pipelines, setting the benchmark for clean, highly optimized systems-level C code running in production proxy runtimes • Own the technical direction and architectural roadmap for line-rate pattern matching, regular expression evaluators, custom dictionary compilers, exact data match (EDM), and indexed document matching (IDM) • Help develop next-generation Data Loss Prevention (DLP) solutions utilizing Machine Learning (ML) models, collaborating with data science teams to successfully deploy and integrate models in high-throughput data paths while balancing inspection capabilities against strict network latency and resource constraints • Establish and enforce exacting architectural standards for multi-threaded C daemons on FreeBSD/Linux, designing robust shared memory structures, high-performance Inter-Process Communication (IPC), lockless concurrency, and memory-safe subsystems • Serve as the technical escalation authority for critical production issues—leading hands-on post-mortem core dump analysis, deep system profiling, and leak detection Who You Are (Success Profile) • You act like an owner with a bias for action, navigating seamlessly between high-level architectural strategy and hands-on execution. • You are a high-trust collaborator who embraces open feedback, communicates with candor and respect, and champions the collective success of the engineering team. • You are customer-obsessed, anchoring technical and design decisions in solving real-world challenges for both internal stakeholders and external users. • You are driven by innovation and intellectual curiosity, continually seeking robust, secure, and scalable approaches to complex systems engineering challenges. • You lead with integrity and high accountability, building trust through consistent, transparent action and technical stewardship. 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 • 10+ years of experience with systems software engineering, including a proven track record of technical leadership (e.g., as a Tech Lead or Principal Engineer) driving the design and delivery of high-performance backend platforms • Advanced hands-on proficiency in C programming on Linux or FreeBSD runtime environments, with deep architectural expertise in Inter-Process Communication (IPC) and shared memory architectures • Expert-level proficiency in production troubleshooting and root-cause analysis, including post-mortem core dump analysis, GDB/LLDB debugging, Valgrind, and system-level performance tracing • Proven track record of mentoring, guiding, and multiplying the impact of systems software engineers across the organization, championing engineering excellence, conducting rigorous design reviews, and fostering continuous technical growth What Will Make You Stand Out (Preferred Qualifications) • Proven ability to leverage AI technologies and workflows to drive measurable operational efficiency • Strong familiarity with Data Loss Prevention (DLP) technologies, including regex evaluation engines, custom dictionary compilers, and EDM (Exact Data Match) / IDM (Indexed Document Matching) profiles • Hands-on experience or familiarity with public cloud environments (specifically AWS and Azure), including deploying, optimizing, or maintaining performance-intensive cloud-native systems #LI-SK3 #LI-HYBRID At Zscaler, we are committed to building a team that reflects the communities we serve and the customers we work with. We foster an inclusive environment that values all backgrounds and perspectives, emphasizing collaboration and belonging. Join us in our mission to make doing business seamless and secure. Our Benefits program is one of the most important ways we support our employees. Zscaler proudly offers comprehensive and inclusive benefits to meet the diverse needs of our employees and their families throughout their life stages, including: • Various health plans • Time off plans for vacation and sick time • Parental leave options • Retirement options • Education reimbursement • In-office perks, and more! Learn more about Zscaler's hybrid working model and benefits here. By applying for this role, you a