Simplesense Cybersecurity Stack is a DoD-compliant, infrastructure-as-code based cybersecurity solution designed to protect Operational Technology (OT) and Industrial Control Systems (ICS) in critical infrastructure environments. The stack is structured around four primary components: **OT Stack:** Small form-factor networking and compute nodes deployed at building edge locations (comm closets) to secure ICS IP traffic at the point of origin. **OT Enclave:** Fault-tolerant, on-premises networking and compute clusters capable of hosting ICS systems and aggregating operational data for relevant stakeholders. **Cloud Enclave:** An IL5-compliant cloud environment providing analytics, data storage, and interfaces to external systems, along with cloud-hosted security tooling for continuous monitoring, antivirus, scanning, patching, and threat detection. **Data Services:** A high-availability database with seamless replication between on-premises and cloud environments, enabling operational and analytical data use across technologies. The solution uses automated deployment pipelines and open frameworks to support scalability and repeatability. It provides continuous monitoring down to ICS Level 1, ongoing patch management, and machine learning-based threat detection and elimination. The architecture is designed to break down information silos and improve situational awareness across OT/ICS environments.