RAGU: A Multi-Step GraphRAG Engine with a Compact Domain-Adapted LLM

Mikhail Komarov, Ivan Bondarenko, Stanislav Shtuka, Oleg Sedukhin, Roman Shuvalov, Yana Dementyeva, Matvey Solovyov, Nikolay Nikitin


Abstract
Graph retrieval-augmented generation (GraphRAG) enhances large language models with structured knowledge, yet existing systems construct knowledge graphs in a single extraction pass, producing noisy entities and brittle retrieval. RAGU, an open-source modular GraphRAG engine, addresses this by separating extraction from consolidation: entities and relations pass through two-stage typed extraction, DBSCAN-backed deduplication, LLM summarization, and Leiden community detection. A key insight motivates a compact extractor: the skills an in-pipeline LLM needs — comprehension, extraction, reasoning over context — are language skills that grow only weakly with model size, unlike factual world knowledge. Accordingly, we train Meno-Lite-0.1, a 7 B model optimized for language skills, which outperforms Qwen2.5-32B on knowledge-graph construction (+12.5% relative harmonic mean) and matches it on English GraphRAG tasks. On GraphRAG-Bench (Medical), RAGU retrieves the most complete context at every factoid level (evidence recall up to 0.84 vs. ≤0.76) and overtakes HippoRAG 2 on synthesis tasks; on multi-hop factoid QA, the apparent HippoRAG 2 advantage is shown to be largely an answer-format artifact. RAGU is installable via ‘pip install graph_ragu‘, runs on a single GPU, and is released under Apache 2.0. Code and model: https://github.com/RaguTeam/RAGU.
Anthology ID:
2026.emnlp-demos.83
Volume:
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing: System Demonstrations
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Sweta Agrawal, Alberto Abad
Venue:
EMNLP
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
880–891
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URL:
https://aclanthology.org/2026.emnlp-demos.83/
DOI:
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Cite (ACL):
Mikhail Komarov, Ivan Bondarenko, Stanislav Shtuka, Oleg Sedukhin, Roman Shuvalov, Yana Dementyeva, Matvey Solovyov, and Nikolay Nikitin. 2026. RAGU: A Multi-Step GraphRAG Engine with a Compact Domain-Adapted LLM. In Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing: System Demonstrations, pages 880–891, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
RAGU: A Multi-Step GraphRAG Engine with a Compact Domain-Adapted LLM (Komarov et al., EMNLP 2026)
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https://aclanthology.org/2026.emnlp-demos.83.pdf