ArchGuard-APR: Architecture-Constraint-Aware Multi-Agent Program Repair Using Repository Graphs and Execution Feedback

Overview & Synopsis

Repository-level automated program repair must reason about more than a localized failing statement. A candidate change can satisfy a narrow test while violating dependency boundaries, modifying an unsafe path, or relying on context that omits relevant repository structure. ArchGuard-APR is an architecture-aware repair prototype that integrates deterministic repository analysis, immutable repository graphs, explicit architecture profiles, graph-guided context retrieval, role-based repair orchestration, patch-policy enforcement, isolated execution feedback, provider cost controls, and canonical source-free evidence. We evaluate the implemented pipeline through an exploratory paired feasibility study, not a confirmatory effectiveness experiment. Six executions were planned; four completed, and two black-4 conditions ended in pre-provider infrastructure attrition. Across two valid paired tasks, baseline and ArchGuard conditions each produced 0/2 successful repairs, and all four completed outputs were classified as invalid patches. The completed executions consumed 35,431 input tokens and 2,737 output tokens, for a total of 38,168 tokens, at a total cost of USD 0.1296325. No effectiveness advantage was observed, and the sample provides no useful inferential basis. The study instead establishes the engineering feasibility of composing architecture constraints with a reproducible repair pipeline and identifies patch validity and infrastructure robustness as the principal targets for future work.