LLM systems architecture: chapter index

HubLast reviewed Oct 16, 2026By Himanshu Ramchandani
Short answer

LLM Systems Architecture and Strategy is my lecture series on the production LLM inference pipeline, in 8 chapters and 40 topics, numbered 1.1 to 8.5. The pipeline itself is drawn in the six zones page, and each chapter opens up one part of it: the physical limits of a model, test-time compute, retrieval, agents, customisation, operations, security and the economics of the whole system. This page maps every topic to the docs page that covers it, so you can read the series in order or jump to one topic.

Chapter 1: the physical limits of a model

Topic Page
1.1 How does text become tokens Tokens
1.2 The internationalization tax Tokens
1.3 Prefill against decode Inference optimization
1.4 The KV cache and paged attention The KV cache
1.5 Sizing GPU memory Capacity and cost modelling

Chapter 2: test-time compute

Topic Page
2.1 What changes when a model thinks Reasoning models
2.2 How a reasoning model searches Reasoning models
2.3 Streaming the thinking tokens Latency and streaming
2.4 Process supervision against outcomes Reasoning models
2.5 Where the hardware budget goes Capacity and cost modelling

Chapter 3: context and retrieval

Topic Page
3.1 Where simple vector search breaks RAG failure modes
3.2 Hybrid search and rank fusion Hybrid search
3.3 Cross encoder reranking Reranking
3.4 Parent and child chunking Chunking strategies
3.5 Prompt compression Context compression

Chapter 4: orchestration and agents

Topic Page
4.1 The model as a kernel Agents and tool use
4.2 The reason and act loop Planning patterns
4.3 Sandboxing tool calls Tool registry and sandbox
4.4 Multi agent patterns Multi-agent systems
4.5 Where autonomy breaks Human in the loop

Chapter 5: model customisation

Topic Page
5.1 Low rank adaptation LoRA and QLoRA
5.2 Quantized fine tuning LoRA and QLoRA
5.3 Quantization formats Quantization
5.4 Speculative decoding Inference optimization
5.5 Swapping adapters in production Serving adapters

Chapter 6: operations and evaluation

Topic Page
6.1 Perplexity and loss Evaluating fine-tuned models
6.2 Task metrics and model judges Check your LLM judge
6.3 The dual guardrail pattern Guardrail sandwich
6.4 Semantic caching Semantic caching
6.5 Evaluation bias Judge prompt overfitting

Chapter 7: security and governance

Topic Page
7.1 Direct prompt injection Prompt injection
7.2 Indirect prompt injection Prompt injection
7.3 The instruction hierarchy System prompts
7.4 System prompt leakage Data leakage and PII
7.5 Refusal bias Test abstention

Chapter 8: economics and strategy

Topic Page
8.1 Build against buy Build vs buy vs partner
8.2 Dynamic model routing Model routing and gateways
8.3 One request traced end to end LLM inference pipeline
8.4 A refund agent post mortem Incident response
8.5 Three rules for production Notebook to production checklist

How to use this index

If you're following the lecture series, read each chapter's pages after the lecture, in order. If you're designing a system, start at the six zones, find the zone you're working on, and use the chapter that covers it.

From the floor

The series started from the first AI System Design Engineering session, where I walked one query through the full production pipeline in about 90 minutes and said each part deserved its own deeper lecture. Those deeper lectures are the 40 topics above.