Security Reliability Engineer

About the Team The Infrastructure Engineering function sits within IT and is responsible for reliably building, deploying, and operating critical on prem and hybrid environments that power internal services and critical R&D environments. This is a new, bootstrap team focused on applying strong Site Reliability Engineering discipline to environments where uptime, safety, recoverability, and security are non-negotiable. The team replaces bespoke, one off infrastructure with standardized infrastructure-as-code building blocks that compound reliability and operational leverage as OpenAI scales. About the Role We are looking for a Security Reliability Engineer to design, build, and operate reliable, secure, and scalable infrastructure that underpins identity, access, endpoint, and shared platform services across the company. In this role, you will own infrastructure and identity systems end to end, from foundational design and provisioning through policy enforcement, upgrades, recovery, and day two operations. You will establish durable, production grade platforms that remove operational friction, enforce security by default, and enable teams to move faster with confidence. This role is well suited for a senior engineer who thrives in ambiguity, enjoys owning complex systems end to end, and raises the reliability and security bar by replacing fragile implementations with standardized, repeatable infrastructure. This role is based in our San Francisco HQ and requires in-office presence. In this role, you will: Set direction and establish strong foundations Define and evolve infrastructure patterns for on prem and hybrid environments, including self hosted platforms, vendor supported systems, and lab environments. Establish standardized, production grade deployment and operational models that replace bespoke implementations. Partner with IT, Security, Identity, and Network teams to ensure infrastructure meets reliability, security, and access requirements by design. Design and mature the production architecture for IAM adjacent platforms such as Microsoft Entra using SRE principles. Establish common management rules and shared resources within Azure subscriptions to ensure consistent, policy aligned operations. Build, operate, and scale reliably Own the full lifecycle of infrastructure systems, including deployment, upgrades, patching, recovery, and ongoing operations. Operate and harden shared infrastructure provisioned through Infra Terraform, ensuring repeatability, auditability, and safe change management. Design and implement infrastructure as code and configuration management to support shared services, identity adjacent systems, and endpoint platforms using tools like Chef, Ansible and Terraform. Build and operate monitoring, alerting, and incident response mechanisms to meet high availability and recoverability targets. Lead incident response and postmortems across infrastructure, identity adjacent platforms, and fleet systems, driving durable fixes and shared learning. Build and operate containerized and platform services, including Kubernetes and Docker-based workloads, using DevOps practices that emphasize reliability, repeatability, and safe change management. Use Git-based workflows as the source of truth for infrastructure and policy changes, enabling review, auditability, and safe, reversible automation. Automate for leverage and safety Identify high leverage automation opportunities that eliminate manual toil and reduce operational risk across infrastructure and access related systems. Implement guardrails, safety mechanisms, and progressive rollout patterns for infrastructure and policy enforcement changes. Ensure automation is safe, observable, and resilient under failure conditions, particularly for shared services and high blast radius systems. Partner and lead through influence Work closely with Security, Identity, Network, Client Platform, and Platform Engineering teams to operate secure, policy enforced infrastructure. Support execution and enforcement of access management policies and privileged access mechanisms owned by partner teams, with a focus on reliability and operability. Coach and elevate engineers and partner teams through design reviews, incidents, and operational improvements. Drive reliability improvements across teams, even without direct authority. You might thrive in this role if you: Have 10 or more years of experience operating and architecting mission critical infrastructure in high reliability environments. Have led the design and maturation of complex on prem, hybrid, or cloud integrated systems, setting durable architectural patterns used by multiple teams. Apply Site Reliability Engineering principles at scale, using observability, automation, and incident learnings to materially reduce risk and operational toil. Operate comfortably in ambiguity, making sound architectural decisions under pressure while staying close to technical detail. Influence cross functiona