RAG Retrieval Engineering: From Hybrid Retrieval to Production Governance

A systematic guide to lexical retrieval, dense retrieval, hybrid fusion, reranking, evaluation, observability, and production governance in RAG systems.

July 17, 2026 · 27 min · 5679 words · Andy SI
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The Role of RRF in RAG: A Simple but Not Universal Retrieval-Fusion Method

Explains the role, calculation, appropriate use cases, and main limitations of RRF in multi-retriever fusion for RAG.

July 15, 2026 · 9 min · 1908 words · Andy SI
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Dense + Sparse Hybrid Search in RAG

An introduction to the roles of dense search, sparse search, RRF, and rerankers in an enterprise RAG retrieval pipeline.

July 15, 2026 · 8 min · 1571 words · Andy SI
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A Guide to Building Enterprise RAG Systems

Use this article as a reference when building an enterprise RAG system.

July 15, 2026 · 8 min · 1523 words · Andy SI
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What AI Engineers Should Learn in 2026

Starting from the trend of platforms absorbing basic RAG pipelines, this article examines the high-premium skills AI application engineers should prioritize in 2026: evaluation and observability, data governance and access control, and deep engineering capabilities for agentic workflows.

May 3, 2026 · 18 min · 3701 words · Andy SI
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The Complete RAG Systems Guide: From Zero to Production

For developers learning AI application engineering, this article maps the complete RAG pipeline from ingestion, chunking, retrieval, reranking, and generation to evaluation and operations, and presents an evolution path from a minimal viable solution to production.

March 27, 2026 · 16 min · 3237 words · Andy SI
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Notes on Anthropic's Contextual Retrieval

Starting from Anthropic’s Contextual Retrieval article and Appendix II, these notes summarize the core method, experimental findings, and RAG architecture principles suitable for production.

March 11, 2026 · 5 min · 994 words · Andy SI
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