Developed and delivered a security-focused feature for the pomerium/pomerium repository, enabling policy-driven access control based on client source IP addresses. The work centered on integrating Source IP-Based Policy Matching with Open Policy Agent, allowing policies to evaluate and enforce access decisions using both individual IPs and CIDR ranges. Implemented in Go, the solution included robust IP parsing and validation logic, as well as comprehensive automated tests to ensure reliability and prevent regressions. This backend development effort enhanced network security and compliance by tying policy evaluation directly to network-origin criteria, supporting maintainable and scalable deployments in policy as code environments.