In this article, you will learn how to implement a hybrid search strategy for RAG systems by combining BM25 lexical search with semantic search, fused together using Reciprocal Rank Fusion. Topics we will cover include: Why hybrid search outperforms either lexical or semantic search alone in retrieval-augmented generation systems. How to implement BM25 lexical search and dense vector semantic search as independent retrieval engines in Python. How to merge both rankings using Reciprocal Rank Fusion (RRF) to produce a final, balanced retrieval result. Let’s get straight to it. Implementing Hybrid Semantic-Lexical Search in RAG Introduction Implementing hybrid search strategies is a critical step in building modern RAG (Retrieval-Augmented Generation) systems , especially when shifting from prototype to production-ready solutions.…