Principal Software Development Engineer - Rust, LLM, Networking
Role summary
We are seeking a Principal Software Development Engineer to join our new AI Security Team. This role involves architecting, developing, and optimizing a high-reliability, low-latency AI security solution using Rust and focusing on distributed systems. You will build core infrastructure, implement gRPC APIs, and enhance performance across the stack, including LLM models. The position requires 12+ years of experience, deep Rust expertise, strong Linux internals knowledge, and skills in performance instrumentation and CI/CD. Preferred qualifications include C/C++ experience, deep understanding of Linux networking, Kubernetes, service meshes, and LLM optimization. This is a hybrid role based in San Jose, CA.
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 hiring a Principal Software Development Engineer to be a founding member of our AI Security Team, offering the chance to build a high-reliability, low-latency AI security solution designed to scale for hundreds of millions of users. In this role, reporting to the Director, Software Development Engineering, you will be responsible for designing and implementing core infrastructure components and distributed systems while collaborating closely with various stakeholders throughout the development lifecycle. This is a hybrid role, reporting in to the San Jose, CA office 3 days a week.
What you’ll do (Role Expectations)
Who You Are (Success Profile)
What We’re Looking for (Minimum Qualifications)
What Will Make You Stand Out (Preferred Qualifications)
#LI-BH1#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.
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:
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 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.
Sample Zscaler interview questions
- 1
Design a service to manage distributed tasks.
system designmedium - 2
Merge a New Interval: Merge a new interval into a list of non-overlapping intervals. Input: intervals = [[1,2],[3,5],[6,7],[8,10],[12,16]], newInterval = [4,8] Output: [[1,2],[3,10],[12,16]] Explanation: The new interval overlaps with [3,5], [6,7], and [8,10], merging them all into the unified block [3,10].
codingmedium - 3
Maximum Depth of an N-ary Tree Find the maximum depth of an N-ary tree. Input: root = [1,null,2,null,3,null,4] Output: 4 Explanation: The tree is essentially a straight line, requiring a traversal that reaches a maximum depth of 4 layers.
codingmedium - 4
Aggressive Cows Maximize the minimum distance between aggressive cows in stalls. Input: stalls = [0,4,3,7,10,9], cows = 3 Output: 4 Explanation: Placing the cows at positions 0, 4, and 10 yields a maximum possible minimum distance of 4 between any two cows.
codingmedium - 5
Decode Ways: Determine the number of valid ways to decode a string of digits. Input: s = "10" Output: 1 Explanation: The string can only be decoded one single way, as the sequence '10' maps exclusively to the letter 'J'.
codingmedium
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