Enhancing repository-level software repair via repository-aware knowledge graphs

Repository-level software repair faces challenges in bridging semantic gaps between issue descriptions and code patches. Existing approaches, which primarily rely on large language models (LLMs), are hindered by semantic ambiguities, limited understanding of structural context, and insufficient reasoning capabilities. To address these limitations, we propose KGCompass with two innovations: (1) a novel repository-aware knowledge graph (KG) that accurately links repository artifacts (issues and pull requests) and codebase entities (files, classes, and functions), allowing us to effectively narrow down the vast search space to only 20 most relevant functions with accurate candidate fault locations and contextual information, and (2) a path-guided repair mechanism that leverages KG-mined entity paths, tracing through which allows us to augment LLMs with relevant contextual information to generate precise patches along with their explanations. Experimental results in the SWE-bench Lite demonstrate that KGCompass achieves state-of-the-art single-LLM repair performance (58.3%) and function-level fault location accuracy (56.0%) across open-source approaches with a single repair model, costing only $0.2 per repair. Among the bugs that KGCompass successfully localizes, 89.7% lack explicit location hints in the issue and are found only through multi-hop graph traversal, where pure LLMs struggle to locate bugs accurately. Relative to pure-LLM baselines, KGCompass lifts the resolved rate by 50.8% on Claude-4 Sonnet, 30.2% on Claude-3.5 Sonnet, 115.7% on DeepSeek-V3, and 156.4% on Qwen2.5 Max. These consistent improvements demonstrate that this graph-guided repair framework delivers model-agnostic, cost-efficient repair and sets a strong new baseline for repository-level repair.