Principal Software Development Engineer - Golang/Python + 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) • Designing, developing, and optimizing high-performance network system architecture and security features to support mission-critical applications • Partnering with Engineering Architects, Product Managers, Solution Architects, and customers to understand complex use cases and review PRDs • Authoring design and functional specifications while driving unit testing and automation to ensure high product quality • Collaborating across cross-functional teams to resolve system-level issues, optimize data path performance, and drive feature innovation • Applying advanced software design principles and troubleshooting expertise to coach junior team members and maintain compliance with federal security certifications Who You Are (Success Profile) • You thrive in ambiguity, easily building the path as you walk it and transforming dynamic challenges into meaningful, scalable solutions. • You act like an owner with a strong bias for action, operating with integrity while moving seamlessly between high-level strategy and hands-on execution. • You are a problem-solver who is energized by finding solutions to complex technical challenges that drive maximum impact. • You are a high-trust collaborator who is ambitious for the team, fostering continuous growth through open, candid, and respectful feedback. • You are a learner with a growth mindset, actively seeking feedback and exploring new technologies to continuously elevate yourself and your partners. What We’re Looking for (Minimum Qualifications) • Demonstrated curiosity and active exploration of AI tools, with a proven history of integrating new technologies to enhance daily workflows and augment problem-solving • Bachelor's or Master's degree in Computer Science or a related field with 10+ years of experience in system engineering for high-performance networking • Expertise in Linux kernel-based networking (L2/L3), stateful firewalls, NAT, network drivers, routing protocols (BGP, OSPF, PIM), and protocols like VLANs, DHCP, DNS, SSL, DTLS, QUIC, IPsec, GRE, and WireGuard • Proficiency in Go and Python programming languages with strong problem-solving skills for debugging complex data path issues • Strong communication and collaboration skills to design scalable systems effectively in a high-accountability environment What Will Make You Stand Out (Preferred Qualifications) • Experience integrating AI/ML frameworks or intelligent data path analysis models to optimize kernel-level networking performance and automate predictive threat detection • Experience with WireGuard, tunneling protocols (GRE, L2VPN), HA protocols (VRRP), alongside certifications like FIPS or FedRAMP and prior experience with TLS, DTLS, and QUIC • Familiarity with cloud computing platforms (AWS or Azure), containerization technologies (Docker, Kubernetes), and advanced virtualization or security solutions #LI-Hybrid #LI-AN4 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 adhere to applicable laws, regulations, and Zscaler policies, including those related to security and privacy standards and guidelines. Zscaler is committed to providing equal employment opportunities to all individuals. We strive to create a workplace where employees are treated with respect and have the chance to succeed. All qualified applicants will be considered for employment without regard to race, color, religion, sex (including pregnancy or related medical conditions), age, national origin, sexual orientation, gender identity or expression, genetic informat