About Zscaler

Serving thousands of enterprise customers around the world including 40% of Fortune 500 companies, Zscaler (NASDAQ: ZS) was founded in 2007 with a mission to make the cloud a safe place to do business and a more enjoyable experience for enterprise users. As the operator of the world’s largest security cloud, Zscaler accelerates digital transformation so enterprises can be more agile, efficient, resilient, and secure. The pioneering, AI-powered Zscaler Zero Trust Exchange™ platform protects thousands of enterprise customers from cyberattacks and data loss by securely connecting users, devices, and applications in any location. 

Named a Best Workplace in Technology by Fortune and others, Zscaler fosters an inclusive and supportive culture that is home to some of the brightest minds in the industry. If you thrive in an environment that is fast-paced and collaborative, and you are passionate about building and innovating for the greater good, come make your next move with Zscaler. 

At Zscaler, our AI and Data Science teams focus on various cybersecurity business-centric use cases including threat detection, policy recommendation, malware detection, content classification, anomaly detection, and AIOps (advanced networking diagnosis). As a Principal Engineer, you will have the opportunity to work on multiple fundamental machine learning problems addressing cloud security, cloud operations, and cloud intelligence.

You will be responsible for leading the development and implementation of advanced machine learning models, mentoring junior team members, and driving strategic AI and data science initiatives. You will have a deep understanding of various stages of an end-to-end Machine Learning project and will be capable of translating business problems into data-driven solutions.

Required Skills

  • 8+ years of experience as a Machine Learning Engineer or Data Scientist, with a proven track record of leading and delivering successful projects
  • Expertise in Python (e.g., pandas, sklearn, pytorch) and SQL
  • Extensive experience in feature engineering, model evaluation, and error analysis
  • In-depth knowledge of Large Language Models (LLMs) and their applications
  • Master's or Ph.D. in Computer Science/Engineering or other technical field; data science concentration is a plus
  • Strong passion for leveraging ML/AI to solve real-world business problems at scale 
  • Exceptional interpersonal, technical, and communication skills
  • Proven ability to learn, evaluate, and adopt new technologies quickly
  • Solid computer science foundation

Preferred Skills

  • Experience in prompt engineering and fine-tuning Large Language Models (LLMs)
  • Expertise in Graph Neural Networks/Knowledge Graphs
  • Proficiency in unsupervised learning (clustering) and evaluation
  • Research experience/publications/patents in relevant areas
  • Familiarity with public cloud services (such as AWS, Google, Azure) and ML automation platforms (such as Kubeflow)
  • Proficiency in various programming languages such as (Py)Spark
  • Deep understanding of operating systems and distributed systems
  • Knowledge of networking and networking security concepts


  • Lead the development of advanced machine learning models to address complex business problems
  • Mentor and guide team members on projects and professional growth
  • Collaborate with cross-functional teams to define project objectives and deliverables
  • Design, implement, and evaluate innovative machine learning solutions, ensuring alignment with business objectives
  • Drive strategic initiatives, identifying opportunities for improvement and innovation
  • Applied research: Stay up-to-date and apply the latest advancements in machine learning and data science 
  • Communicate complex data science concepts to non-technical stakeholders and drive data-driven decision-making across the organization



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 proud to be an equal opportunity and affirmative action employer. We celebrate diversity and are committed to creating an inclusive environment for all of our employees. All qualified applicants will receive consideration 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 characteristics 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. For additional information about the federal requirements, click here.

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.

Apply for this Job

* Required
resume chosen  
(File types: pdf, doc, docx, txt, rtf)
cover_letter chosen  
(File types: pdf, doc, docx, txt, rtf)

Voluntary Self Identification

At Zscaler, we value diversity, equity, inclusion and belonging. We invite you to voluntarily respond to the question(s) below to help us measure the effectiveness of our outreach and recruitment. Responding is entirely voluntary and will not impact your application process. All responses will be kept confidential and handled in accordance with applicable privacy laws. Thank you for helping us create a more inclusive workplace.

Sex (Select one) *

Our system has flagged this application as potentially being associated with bot traffic. Please turn off any VPNs, clear your browser cache and cookies, or try submitting your application in a different browser. If this issue persists, please reach out to our support team via our help center.
Please complete the reCAPTCHA above.