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. 

Our Engineering team built the world's largest cloud security platform from the ground up, and we keep building. With more than 100 patents and big plans for enhancing services and increasing our global footprint, the team has made us and our multitenant architecture today's cloud security leader, with more than 15 million users in 185 countries. Bring your vision and passion to our team of cloud architects, software engineers, security experts, and more who are enabling organizations worldwide to harness speed and agility with a cloud-first strategy.

As a Principal Software Engineer, you will work on the requirements, design and code components of a very large scale distributed system with a sense for performance and scalability, troubleshoot issues with hawkish skills, work with Operations and Support to help manage a healthy cloud and happy customers and at the end of the day – display accountability in areas assigned to you.

We develop solutions that are transforming the internet security business, and millions of users rely daily on our service for data protection and comprehensive security. We also provide real-time analytics to our customers for unmatched visibility and maintain a state-of-the-art NOC. The development team works on the complete L1-L7 n/w stack, Zscaler OS, Device Drivers, web filtering, policy enforcement, next-gen firewall, sandboxing, DLP, Digital Experience and mobile user solutions. Being responsive to our customers and delivering industry-leading, mission-critical solutions require precise engineering and a philosophy of continuous improvement. The Zscaler Zero Trust SD-WAN Branch Connector provides Zero Trust Security for users and application traffic originating from a remote branch to internet, cloud or another remote branch or data center. The Branch Connector eliminates the network attack surface by establishing direct branch-to-internet and branch-to-private app connections using a full proxy architecture. It also simplifies branch communications by eliminating complex routing, virtual private networks (VPNs), and firewalls while allowing for flexible forwarding and simple policy management by using the Zscaler Internet Access (ZIA) and Zscaler Private Access (ZPA) policy framework.

We're looking for an experienced Principal Software Engineer to join our Core ZIA team. Reporting to the Sr. Director, ZTNA and Inline applications, you'll be responsible for:

  • Work with a team of software engineers, architects, and product managers to create performance and scalable solutions that meet the demands of our customers.
  • Lead the development of the data path software, focusing on high-performance, low latency data forwarding and packet processing.
  • Participate in all phases of the product development cycle, from definition, design, through implementation and testing. Develop functional specifications, assess task requirements and scheduling, and participate in the development, debugging and support.
  • Conduct code reviews to maintain code quality and maintain documentation for the code, including design specifications and user guide.

What We're Looking for (Minimum Qualifications)

  • BS degree in CS/CE or equivalent is required with 12+ years software development experience building large-scale commercial networking and security applications.
  • Hands-on programming in C, debugging memory corruption, Multithreading, SMP and in depth knowledge in Data-Structures and Algorithms along with good Unix/Linux Kernel.
  • Hands on Experience troubleshooting networking/system issues using tools like perf, gdb, Wireshark, tcpdump, curl, wget, etc.
  • Software design concepts - HA, failover redundancy, load balancing, optimizing for scale and performance
  • Experience with network control-plane protocols like DHCP, VRRP, CARP, OSPF, BGP

What Will Make You Stand Out (Preferred Qualifications)

  • Experience in user space data plane such as OVS-DPDK.
  • Experience with FreeBSD-based networking solutions and/or ESXi Hypervisor/KVM infra & file system knowledge.
  • Experience with software-defined networking solutions like SDN, SD-WAN, etc.

#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
$175,000$250,000 USD

At Zscaler, we believe that diversity drives innovation, productivity, and success. We are looking for individuals from all backgrounds and identities to join our team and contribute to our mission to make doing business seamless and secure. We are guided by these principles as we create a representative and impactful team, and a culture where everyone belongs. For more information on our commitments to Diversity, Equity, Inclusion, and Belonging, visit the Corporate Responsibility page of our website.

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!

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.

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