How to Build Hybrid Search RAG Pipelines with BM25, RRF Fusion, and Cross-Encoder Reranking
Pure vector search fails on roughly 40% of real-world queries. This 2026 production guide shows how to combine BM25 sparse retrieval, dense embeddings, RRF fusion, and a cross-encoder reranker into a single pipeline that pushes recall@10 from 78% to 91% — with working Python code.