Principal Machine Learning Engineer

About Zscaler Zscaler is a pioneer and global leader in zero trust security. The world’s largest businesses, critical infrastructure organizations, and government agencies rely on Zscaler to secure users, branches, applications, data & devices, and to accelerate digital transformation initiatives. Distributed across more than 160 data centers globally, the Zscaler Zero Trust Exchange platform combined with advanced AI combats billions of cyber threats and policy violations every day and unlocks productivity gains for modern enterprises by reducing costs and complexity. Here, impact in your role matters more than title and trust is built on results. 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 champion an “AI Forward, People First” philosophy to help us accelerate and innovate, empowering our people to embrace their potential. If you’re driven by purpose, thrive on solving complex challenges and want to make a positive difference on a global scale, we invite you to bring your talents to Zscaler to help shape the future of cybersecurity. Role We are looking for a Principal Machine Learning Engineer to join our ML/AI team. This is a hybrid role based in San Jose, CA, reporting to the VP, AI and ML within the Engineering department. You will drive innovation within our growing ML/AI team, focusing on critical cybersecurity use cases like agentic frameworks, threat detection, and anomaly detection. Your work will enable organizations worldwide to harness speed and agility through a cloud-first strategy while solving complex security challenges at scale. What you’ll do (Role Expectations) Lead the design and development of cutting edge, production ready AI/ML systems and pipelines, cybersecurity applications and provide technical guidance to junior and mid-level engineers Optimize existing machine learning pipelines for improved efficiency and scalability Explore and experiment with advanced AI techniques and architectures to solve complex cybersecurity problems while staying updated on the latest advancements in AI Collaborate with cross-functional teams to define project requirements and ensure alignment with business objectives Ensure systems and applications meet reliability, scalability and performance requirements 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) Bachelor's degree in Computer Science, or a related technical field 10+ years of experience as a Machine Learning Engineer or Scientist, with a proven track record of delivering successful projects in cybersecurity Strong proficiency in Algorithms, Game Theory and Optimization, Verification, and ML libraries and frameworks Extensive experience in data modeling, feature engineering, model development, and error analysis Excellent communication skills with the ability to translate complex technical concepts to stakeholders and peers What Will Make You Stand Out (Preferred Qualifications) Proven track record of designing, building and shipping end-end applications at scale, with familiarity with multi-agent systems and orchestration frameworks Deep expertise with cloud infrastructure such as AWS or GCP for AI workloads Strong experience with agent architectures and SOTA AI frameworks, along with contributions to open-source ML projects or top-tier research publications #LI-JM1 #LI-Hybrid Zscaler’s salary ranges are benchmarked and are determined by role and level. The range displayed on each job posting reflects the minimum and maximum target for new hire salaries for the position across all US locations and could be higher or lower based on a multitude of factors, including job-related skills, experience, and relevant education or training. The base salary range listed for this full-time position excludes commission/ bonus/ equity (if applicable) + benefits. Base Pay Range $182,000—$260,000 USD 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 Future of Work strategy, 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 information, disability status, protected veteran status, or any other characteristic protected by federal, state, or local laws. See more information by clicking on the Know Your Rights: Workplace Discrimination is Illegal link. Pay Transparency Zscaler complies with all applicable federal, state, and local pay transparency rules. Zscaler is committed to providing reasonable support (called accommodations or adjustments) in our recruiting processes for candidates who are differently abled, have long term conditions, mental health conditions or sincerely held religious beliefs, or who are neurodivergent or require pregnancy-related support.