Principal Engineer (Auth)

Menlo Security's mission is enabling the world to connect, communicate and collaborate securely without compromise. COVID-19 has made our mission all the more real. We support customers across various enterprises including Fortune 500 companies, 9/10 of the largest global banks and the Department of Defense.

The world has fundamentally changed. We are growing from 400 employees into the next phase of our journey, and we need passionate talent filled with empathy and agility. The right candidate for the job is ethical, hyper-organized, fanatical about seeing things through to completion, service-oriented, and humble enough to take feedback and coaching yet confident enough to provide feedback and coaching.

Menlo is well-funded for growth and our investors are second to none. They include Vista Equity Partners (“Vista”), General Catalyst, JPMC, American Express, HSBC, and Ericsson Ventures.

We're looking for a principal engineer to own our authentication service. Authentication is at the root of our browser security product. Every user request flows through it, so the decisions you make here have real consequences: for security, for performance, and for how the system evolves over time. You'll work with a small team that values autonomy and ships without a lot of process overhead. You'll bring technical leadership to an existing system and team, and you'll own what you build together.

What We're Looking For

Strong Systems Programming Background: Extensive hands-on experience building and maintaining production systems in Rust or Go, with a preference for languages that offer strong safety guarantees in critical applications.

Passion for the Craft: You care about building software the right way. Correctness, scalability, and maintainability matter to you beyond just getting a feature out the door.

Focus on Performance Optimization: Demonstrated ability to optimize for latency and throughput in networked applications, using profiling tools and efficient concurrency models to handle demanding workloads.

Security-Oriented Engineering Practices: Strong background in implementing secure systems, with a proactive approach to threat modeling, vulnerability mitigation, and ensuring data integrity in distributed environments.

Expertise in Asynchronous Programming: You've built and operated async services that handle high concurrency in production. You understand back-pressure, cancellation, and the failure modes that come with non-blocking I/O.

Problem-Solving for Legacy Rewrites: Experience refactoring legacy codebases into more robust architectures, evaluating trade-offs in language choices while favoring those that align with long-term maintainability and security.

Commitment to Testing and Verification: History of employing comprehensive testing strategies, including fuzzing, property-based testing, and integration tests, to validate correctness under various failure scenarios.

Collaborative Technical Leadership: Ability to articulate and defend architectural decisions in team settings, while mentoring others on best practices for secure software development.

Strategic Use of AI Tools: Proficiency in leveraging LLMs thoughtfully and selectively to boost productivity, while critically assessing outputs to prevent 'AI slop' and ensure system-wide architectural correctness, maintainability, and alignment with broader engineering goals.

Ownership: Be responsible for the full lifecycle of the services you build, working closely with existing team members who have deep context on the system.

Communication: Work with your team, and across teams, to understand customer needs, refine requirements, implement, review, and deliver changes.

Requirements

• 8+ years of experience building and operating production systems

• Experience in Rust or Go strongly preferred
  

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Why Menlo?

Our culture is collaborative, inclusive, and fun! We have five core values: Stay Aligned, Get It Done, Customer Empathy, Think Creatively and Help Each Other Out. We believe in open communication, supporting new ideas, and sharing a mutual mindset of what we’re aiming to achieve together. There are tremendous opportunities to take initiative, implement new ideas, and have a hand in building a legacy.

All qualified applicants will receive consideration for employment without regard to race, sex, color, religion, sexual orientation, gender identity, national origin, protected veteran status, or on the basis of disability.

TO ALL AGENCIES: Please, no phone calls or emails to any employee of Menlo Security outside of the Talent organization. Menlo Security’s policy is to only accept resumes from agencies via Ashby (ATS). Agencies must have a valid services agreement executed and must have been assigned by the Talent team to a specific requisition. Any resume submitted outside of this process will be deemed the sole property of Menlo Security. In the event a candidate submitted outside of this policy is hired, no fee or payment will be paid.