Member of Technical Staff - Security Engineer

OUR MISSION Reflection’s mission is to build open superintelligence and make it accessible to all. We’re developing open weight models for individuals, agents, enterprises, and even nation states. Our team of AI researchers and company builders come from DeepMind, OpenAI, Google Brain, Meta, Character.AI, Anthropic and beyond. ROLE OVERVIEW Reflection.AI http://Reflection.AI is looking for a Member of Technical Staff - Security Software Engineer to build our Application Security function from the ground up while contributing to a broad array of projects across the entire Security Engineering organization. You will have a high level of autonomy to architect solutions and drive them through both technical and organizational adversity. This role is ideal for an engineer who thrives in high-ownership, low-structure environments and has a strong "0 to 1" mindset. KEY RESPONSIBILITIES - Contribute engineering cycles to a broad array of key projects across the Security organization ranging from our agentic AI incident detection & response SOC to long-running internal AI agents - Implement security controls around AI agents, including sandboxes, identity, and authorization systems - Define software supply chain security strategy, tooling, and infrastructure including SCA/SBOM analysis - Roll out controls to rapidly ingest and act on emerging supply chain attacks - Develop and maintain a comprehensive threat model of our software stack - Drive our pentesting program with prioritization guided by your threat model - Define and socialize foundation secure coding practices and architecture patterns relevant to AI/ML systems - Integrate SAST tools into CI/CD pipelines for continuous vulnerability analysis - Define and implement a comprehensive Secure Software Development Lifecycle REQUIRED QUALIFICATIONS - Strong proficiency with Python or Golang - Track record of architecting and building complex software systems - Familiarity with common application logic exploit vectors - Experience implementing and rolling out cross-functional projects that impact many teams - AI-native engineering workflow - Experience working with Kubernetes - Experience working with AWS and/or GCP - A strong interest in growing in multiple sub-specialties within security, including infrastructure security, incident detection & response, and digital forensics - Willingness to flex into cross-functional projects across multiple pillars of Security as needed - Experience building programs from 0 to 1 WHAT WE OFFER: We believe that to build superintelligence that is truly open, you need to start at the foundation. Joining Reflection means building from the ground up as part of a small talent-dense team. You will help define our future as a company, and help define the frontier of open foundational models. We want you to do the most impactful work of your career with the confidence that you and the people you care about most are supported. - Top-tier compensation: Salary and equity structured to recognize and retain the best talent globally. - Health & wellness: Comprehensive medical, dental, vision, life, and disability insurance. - Life & family: Fully paid parental leave for all new parents, including adoptive and surrogate journeys. Financial support for family planning. - Benefits & balance: paid time off when you need it, relocation support, and more perks that optimize your time. - Opportunities to connect with teammates: lunch and dinner are provided daily. We have regular off-sites and team celebrations.