SecReviewAgent: Context-Aware Security Review of Infrastructure-as-Code Using Persistent Architecture Memory
Security review of Infrastructure-as-Code (IaC) in enterprise cloud platforms requires understanding not only configuration diffs, but also how those changes interact with existing architecture and risk controls. In financial-engineering environments, IaC changes can directly affect data perimeter boundaries, model-serving paths, entitlement controls, and operational resilience. Current tools often analyze pull requests in isolation, missing security implications that emerge only from cross-resource context. This paper presents SecReviewAgent, an LLM-powered IaC security review system that maintains persistent architecture memory across pull request reviews. On first encounter with a repository, SecReviewAgent scans IaC files to build an architecture model, persists that model to object storage, and reuses it in subsequent reviews to interpret changes in context. We evaluate the system on 847 pull requests from 23 repositories spanning financial services, healthcare, e-commerce, and developer tooling. Results show a $2.4 \times$ improvement in context-dependent issue detection recall over a no-context LLM baseline, precision of 0.89, F1 of 0.83, and a 73% latency reduction on warm reviews by avoiding full repository rescans. A controlled user study with 42 practitioners indicates reduced median review time and improved finding accuracy. The paper contributes a persistent-memory design for LLM-based code review, algorithms for repository context construction and incremental update, and an empirical evaluation of context-aware IaC security review in realistic settings.