Senior Infrastructure Security Engineer

Crusoe is on a mission to accelerate the abundance of energy and intelligence . As the only vertically integrated AI infrastructure company built from the ground up, we own and operate each layer of the stack — from electrons to tokens — to power the world's most ambitious AI workloads. When you join Crusoe, you join a team that is building the future, faster. We're in the midst of the greatest industrial revolution of our time. The demand for AI compute is boundless, and power is a bottleneck. We're solving that — with an energy-first approach that makes AI infrastructure better for the world and faster for the people innovating with AI. We're looking for problem-solving, opportunity-finding teammates with a sense of urgency, who believe in the scale of our ambition and thrive on a path not fully paved — people who want to grow their careers alongside a team of experts across energy, manufacturing, data center construction, and cloud services. If you want to do the most meaningful work of your career, help our customers and partners advance their AI strategies, and be part of a high-performing team that believes in each other, come build with us at Crusoe. About This Role Crusoe’s mission is to accelerate the abundance of energy and intelligence. We’re seeking a Senior Infrastructure Security Engineer dedicated to establishing a high-assurance security posture through deep visibility and granular access controls. In this role, you will leverage advanced tooling like Wiz to maintain an uncompromising security posture, using infrastructure service building as the primary mechanism to enforce these standards across our global compute platform. What You’ll Be Working On Drive comprehensive Infrastructure Security Posture Management (ISPM) and cloud-native visibility, leveraging tools like Wiz to identify risks, drift, and misconfigurations across cloud and on-prem infrastructure. Championing Infrastructure-as-Code (IaC) standards (e.g., Terraform) to enforce secure defaults, immutability, and drift detection Driving Infrastructure Security Access and Posture Management for both cloud and on-prem infrastructure to ensure comprehensive visibility and governance Building automated security guardrails embedded directly into CI/CD and deployment pipelines Operate security-as-a-service platforms (e.g., secrets management, certificate lifecycles) designed to reinforce our security posture and simplify developer access workflows. Designing and operating certificate lifecycles (X.509, SSH) to support secure machine-to-machine trust Contribute to identity-centric access control systems, specifically focusing on short-lived, Just-In-Time (JIT) access models, Zero Trust, and automated authorization policies to eliminate standing privileges. Securing core network foundations, including global DNS architecture, service discovery, and network authentication systems Designing and maintaining authentication controls for network infrastructure to ensure secure, monitored access Partnering closely with infrastructure, platform, and SRE teams to identify and remediate security gaps in foundational systems What You’ll Bring to the Team 5-8 years of hands-on experience in infrastructure engineering, SRE, or security engineering Deep understanding of security principles across the stack, from Linux and container runtimes to cloud control planes Proven experience using Infrastructure-as-Code (Terraform) to manage complex, multi-environment infrastructure at scale Strong knowledge of cryptography, secrets management, PKI, and modern authentication standards Experience securing public cloud (AWS, GCP) and/or bare-metal environments Strong networking fundamentals, including routing, segmentation, firewalls, and Zero Trust architectures Hands-on experience with Kubernetes and container security, including secure secrets injection into microservices Fluency in at least one programming language (Go or Python preferred) for automation and