Senior Security Engineer at LMArena
Location: SF Bay Area/Remote
Type: Full-Time
Secure the Future of AI: Join LMArena as a Senior Security Engineer
LMArena is looking for a seasoned Security Engineer to architect and implement a secure-by-default infrastructure for our cutting-edge AI evaluation platform. If you're passionate about safeguarding critical systems, thinking like both an attacker and a defender, and building trust at scale, this is your opportunity to make a real impact.
As a Senior Security Engineer, you'll be at the forefront of protecting a platform used by leading AI labs and researchers to evaluate and improve AI models. Your work will directly contribute to a more transparent, reliable, and safe AI ecosystem.
What You'll Do:
Design and deploy foundational security infrastructure, including IT systems, 2FA, VPNs, login controls, and suspicious account filtering.
Integrate tools and processes to proactively detect and mitigate supply chain vulnerabilities.
Conduct comprehensive security audits of access patterns across compute, storage, and databases to prevent credential leaks and PII exposure, strictly enforcing the Principle of Least Privilege (PoLP).
Develop and enforce robust security policies, standards, and procedures throughout the organization.
Lead regular vulnerability assessments, penetration testing, and code reviews to identify and address security weaknesses.
Build and maintain real-time monitoring systems for threat detection and incident response.
Collaborate closely with engineering, product, and operations teams to ensure seamless security integration.
Ensure compliance with relevant regulations (GDPR, CCPA) and industry standards through regular audits and updates.
Champion company-wide security awareness through engaging training programs, comprehensive documentation, and cross-team guidance.
Scale security operations and build/lead high-performing security teams to address evolving challenges as the company grows.
Why LMArena?
LMArena, created by researchers from UC Berkeley’s SkyLab, is the leading open platform for accessing, exploring, and interacting with state-of-the-art AI models. Our community-driven leaderboard, powered by side-by-side comparisons and user votes, is revolutionizing AI transparency and grounded in real-world usage.
Trusted by industry giants like Google, OpenAI, Meta, and xAI, LMArena is rapidly becoming essential infrastructure for human-centered AI evaluation at scale. With over one million monthly users and growing developer adoption, our impact is shaping the next generation of safe and aligned AI systems.
Our work is frequently referenced by leading figures in the AI space, including Sundar Pichai, Jeff Dean, Elon Musk, and Sam Altman.
High Impact: Your contributions will directly influence the security of a platform used daily by the world's most advanced AI labs.
Global Reach: Develop data infrastructure that powers millions of real-world AI evaluations, shaping AI reliability across industries.
Exceptional Team: Join a small, highly talented team with experience from Google, DeepMind, Discord, Vercel, UC Berkeley, and Stanford.
What You'll Bring:
5+ years of experience in software engineering or security engineering, with a focus on building secure, scalable systems.
Proven expertise in securing IT systems, networks, and cloud environments (e.g., AWS, Azure, GCP).
In-depth knowledge of firewalls, IDS/IPS, endpoint protection, and vulnerability management tools.
Strong understanding of threat modeling, risk assessment, and designing effective mitigation strategies for real-world attack scenarios.
Hands-on experience implementing common security tools and practices, including VPNs, MFA/2FA, intrusion detection, secrets management, and secure deployment pipelines.
Experience designing and deploying infrastructure security measures across cloud environments, identity systems, and access controls (e.g., Okta, OneLogin).
Experience maintaining company hardware
Excellent communication skills and the ability to collaborate effectively with both technical and non-technical stakeholders, clearly articulating risks and tradeoffs.
Bonus: Experience in adversarial ML, trust & safety systems, or securing user-driven platforms with voting or reputation systems.
Our Tech Stack:
NextJS
Tailwind
ShadCN
HonoJS
Postgres
Vitest
Perks & Benefits:
Competitive salary range: 210k - 231k + equity (Actual compensation is determined based on experience, skills, and location).
Meaningful equity in a rapidly growing company.
Comprehensive healthcare coverage (medical, dental, vision).
The unique opportunity to work on cutting-edge AI technology with a small, mission-driven team.
A culture that values transparency, trust, and making a positive impact on the AI community.
Come help us build the platform where everyone can explore and shape the future of AI.