Security Engineer - Member of Technical Staff

About the Company Simile is The Simulation Company. We simulate human behavior to keep people at the center of the decisions that shape the world. With AI, anyone can create a product, a campaign, a policy, or a script — the bottleneck has moved upstream. The hard question is no longer whether you can create something, but what to create, for whom, and how to bring it to life. Those are fundamentally human decisions, and they shouldn't be left to chance or handed off to an algorithm. We're building the infrastructure to understand human behavior at scale and to represent humans in an increasingly agentic world. Our mission is to simulate all eight billion people on earth. We launched five months ago. Since then we've grown revenue 5x, built a new foundation model for human behavior that has run tens of millions of simulations for F100 enterprises, trained a first-of-its-kind confidence model that predicts the accuracy of every simulation, and released the first product that lets organizations verifiably predict the future. The world's leading companies use Simile to make business-critical decisions — from consumer leaders like CVS Health and Wealthfront to professional services organizations like Deloitte and Gallup — strategizing product launches, entering new markets, and forecasting earnings calls. We've raised over $200M at a $2B post-money valuation led by Greenoaks, wi [... source excerpt omitted ...] romising privacy and world-class defenses. We operate at the intersection of application security, AI safety, and enterprise-grade privacy to protect our foundation models and our customers' most sensitive data. We organize our work into three core pillars: Application Security: Partnering with engineers to "shift left," conducting threat models and secure design reviews to catch vulnerabilities before they reach production. Product and AI/ML Security: Defending our generative agents against emerging threats like prompt injection, data poisoning, and model extraction. Infrastructure & Compliance: Hardening our multi-cloud footprint (AWS/GCP) and automating identity management [... source excerpt omitted ...] who thrives on securing novel AI products. You will own the security roadmap, ensuring our platform is resilient, compliant, and stays ahead of an ever-evolving threat landscape. Responsibilities Customer Security & Trust: Partner with our largest enterprise customers to navigate the procurement process , leading technical discussions regarding security agreements, providing comprehensive posture overviews, and ensuring alignment on rigorous data handling requirements Lead Secure Design: Conduct threat modeling and secure design reviews for new features, ensuring security is a core consideration from initial design through implementation. Automate Defenses: Develop tooling and "pa