LeetLLM
Tracks
Intermediate22 lessons

RAG and Search Systems

Learn document ingestion, retrieval, reranking, evaluation, and secure enterprise RAG as one coherent path.

Builders working on search, support bots, internal knowledge assistants, and document QA.

You can design a retrieval pipeline, debug faithfulness failures, and choose vector, lexical, and graph retrieval pieces deliberately.

  1. 1Static to Contextual EmbeddingsTurn token IDs into vectors, learn what nearby usage captures, and see why a word such as charge needs sentence-dependent representations.Core LLM FoundationsMedium15 min
  2. 2Sentence Embeddings & Contrastive LossLearn how contrastive losses train sentence embeddings, why hard negatives matter, and how retrieval systems combine bi-encoders, rerankers, and dimension tradeoffs.Transformer Deep DivesHard40 min
  3. 3Embedding Similarity & QuantizationLearn vector scoring contracts, evaluate Matryoshka widths, and measure scalar, product, and binary quantization before deploying compressed retrieval.Transformer Deep DivesHard40 min
  4. 4Dimensionality Reduction for EmbeddingsShrink and inspect embedding indexes without guessing: measure recall while testing PCA, projections, native shortening, and quantization.Applied LLM EngineeringMedium20 min
  5. 5File Ingestion for AITurn PDFs, scans, HTML, and Markdown into faithful evidence records with provenance and quality checks before retrieval.Core LLM FoundationsMedium14 min
  6. 6Chunking StrategiesTurn clean documents into retrieval units that preserve answers, citations, and measurable search quality.Core LLM FoundationsMedium14 min
  7. 7Core Retrieval AlgorithmsBuild and evaluate the evidence-selection stage of a technical-docs assistant with BM25, dense similarity, rank fusion, reranking, and approximate search audits.ML Algorithms & EvaluationMedium16 min
  8. 8Production RAG PipelinesDesign a secure, traceable RAG service around versioned policy evidence, grounded answers, abstention, release gates, and latency budgets.Applied LLM EngineeringMedium17 min
  9. 9Vector DB Internals: HNSW & IVFLearn how approximate nearest neighbor indexes use HNSW, IVF, and Product Quantization to balance speed, recall, and memory in production vector databases.Advanced Agents & RetrievalHard35 min
  10. 10Hybrid Search: Dense + SparseUpgrade a permission-safe RAG retriever with BM25, semantic scores, rank fusion, and recall gates for exact codes and paraphrased policy questions.Applied LLM EngineeringMedium18 min
  11. 11Reranking and Cross-Encoders for RAGTurn a permission-safe hybrid candidate list into precise context using cross-encoder reasoning, ordering metrics, latency gates, and traceable evidence selection.Applied LLM EngineeringMedium15 min
  12. 12RAG Evaluation for Reliable AnswersEvaluate a permission-safe RAG answer trace with context, claim, citation, failure-attribution, and release gates before automating softer judgments.Applied LLM EngineeringMedium13 min
  13. 13LLM-as-a-Judge EvaluationAdd calibrated soft judgments to a RAG evaluation trace without letting an LLM override deterministic evidence gates.Applied LLM EngineeringMedium18 min
  14. 14Hallucination Detection & MitigationBuild a claim-level grounding gate for incident updates that verifies evidence, catches confident fabrication, abstains safely, and records release traces.Applied LLM EngineeringMedium15 min
  15. 15LLM Observability & MonitoringTurn claim-level answer traces into production metrics, actionable alerts, privacy-safe debugging records, and reproducible incident evidence.Applied LLM EngineeringMedium18 min
  16. 16Advanced RAG: HyDE & Self-RAGLearn how query rewriting, HyDE, Self-RAG, and Corrective RAG change retrieval control, and how to evaluate their cost and evidence quality.Advanced Agents & RetrievalHard33 min
  17. 17GraphRAG & Knowledge GraphsLearn how GraphRAG uses entity graphs, hierarchical community reports, and embeddings to retrieve evidence for relationship-heavy and corpus-level questions.Advanced Agents & RetrievalHard37 min
  18. 18RAG Security & Access ControlLearn how document ACLs, tenant isolation, retrieval-time authorization, output checks, and audit logs reduce private-data leakage risk in enterprise RAG.Advanced Agents & RetrievalHard37 min
  19. 19Model Versioning & DeploymentTurn an evaluated LLM change into an immutable release bundle, promote it through measured traffic, and roll back without losing lineage.Applied LLM EngineeringMedium19 min
  20. 20Semantic Caching & Cost OptimizationReuse stable policy answers across paraphrased questions without crossing release, access, or freshness boundaries; then prove the cache is both safe and worth serving.Applied LLM EngineeringMedium17 min
  21. 21Capstone: Document QAShip a policy-evidence service with controlled admission, cited answers, abstention, replayable eval rows, and source-bound semantic adjudication.Portfolio CapstonesHard36 min
  22. 22LLM-Powered Search EngineMaster the architecture of an end-to-end AI search engine, covering freshness routing, hybrid retrieval, evidence packing, citation verification, and streaming synthesis.System Design CapstonesHard35 min