Cloud Custodian (c7n) is a rules engine for managing public cloud accounts and resources across AWS, Azure, and GCP environments. The tool enables organizations to define policies in YAML configuration files to maintain well-managed cloud infrastructure that meets security and cost optimization requirements. The platform consolidates various administrative scripts into a unified tool with centralized metrics and reporting capabilities. Users can create policies that target specific resource types such as EC2 instances, Auto Scaling Groups, Redshift clusters, CosmosDB databases, and PubSub topics using a vocabulary of filters and actions. Cloud Custodian provides real-time compliance enforcement for security policies including encryption requirements and access controls, tag governance, and cost management through automated garbage collection of unused resources and off-hours resource management. The tool integrates with cloud-native serverless capabilities to enable real-time policy enforcement with built-in provisioning. The platform supports infrastructure as code workflows by running policies on IaC assets, providing feedback directly on developer workstations or within CI/CD pipelines. This capability allows organizations to identify and address policy violations before resources are deployed to production environments.