The Learning Library
Stack
Stack is the part of Nybble you read when the news isn’t enough. Snack tells you what shipped; Stack explains how it works and why it matters. It holds three kinds of material: Tracks, multi-lesson courses that take a topic from first principles to production; Library, research papers and whitepapers with a plain-English note on why each one matters; and Explainers, single-concept pieces for the ideas that keep coming up.
The problem Stack is built for is sequencing. Most AI material online is a pile of disconnected posts written at different times against different model versions, and working out what to read in what order is most of the effort. Tracks fix the order.
Guided Courses
Tracks
14 courses, 211 written lessons. Each course is a sequence, not a collection — lesson 1 assumes nothing and every lesson after it builds on the one before. Lessons run 500–2,500 words with worked examples and code where code is the clearest explanation.
The courses are grouped into four phases, which is roughly the order the work happens in:
Understand
How the models actually work, from the tokenizer up.
- Tokenization, Inside and Out · 14 lessonsBPE, WordPiece, Unigram, SentencePiece, tiktoken — every algorithm, every tradeoff, every production implication.
- Attention Mechanisms, from First Principles · 16 lessonsSelf-attention, multi-head, KV cache, MQA, GQA, MLA, FlashAttention — the complete mechanism that makes transformers work.
- The Transformer Architecture · 16 lessonsFrom 'Attention Is All You Need' to GPT-4 and Llama 3 — every layer, every design choice, every scaling decision.
Build
Turning a model into an application that does something useful.
- Building RAG Systems · 23 lessonsGround language models in your own knowledge — retrieval, reranking, evaluation, and production, end to end.
- Prompt Engineering and Context Design · 12 lessonsSystem prompts, structured outputs, chain-of-thought, and the context engineering patterns that make LLMs reliable in production.
- Vector Databases, Inside and Out · 17 lessonsAlgorithms, architecture, and operations — from HNSW internals to production at scale.
- AI Agents in Production · 16 lessonsFrom the agent loop to multi-agent systems — LangGraph, MCP, tool calling, memory, and the guardrails that make agents safe to ship.
Ship
Everything between a working prototype and a system you can operate.
- LLM Evaluation and Testing · 14 lessonsGolden datasets, LLM-as-a-judge, regression testing, and CI/CD gates — the engineering discipline that separates demos from products.
- LLM Fine-Tuning for Production · 14 lessonsLoRA, QLoRA, dataset engineering, and the decision framework for when fine-tuning is the right answer — and when it isn't.
- LLMOps: Serving and Operating LLMs · 15 lessonsModel serving, inference optimization, guardrails, observability, and cost control — the engineering that keeps LLM systems running.
Evolve
The patterns arriving now — agent harnesses, self-improvement, compound systems.
- Loop Engineering and Agent Harnesses · 14 lessonsHarness design, context management, subagent orchestration, evaluation-as-steering, and the Claude Agent SDK — the infrastructure layer that makes agents reliable.
- Autonomous and Headless Agents · 14 lessonsDurable execution with Temporal, event-driven triggers, sandbox isolation, crash recovery, and the governance framework for agents that run without human oversight.
- Self-Improving AI Systems · 13 lessonsAutomated prompt optimization, log-driven harness patching, principle extraction, memory-driven evolution, and the governance framework for systems that modify themselves.
- Compound AI Systems · 13 lessonsMulti-model routing, cascading, the classifier-generator-verifier triad, AI gateways, protocol composition, and the systems engineering that turns models into products.
Research Library
Library
6 papers, whitepapers and patents that are worth the time, each with a short note on what it actually changed. Abstracts tell you what a paper claims; the note tells you why it ended up mattering, or why it didn’t.
Every entry links out to the original source. The Library is meant as a filter and a starting point, not a replacement for reading the paper.
Concept Library
Explainers
Single-concept pieces — one idea, a few minutes, no prerequisites. Where a Track teaches a subject in order, an Explainer answers one question you hit in the middle of something else.
Explainers is being rebuilt and isn’t live yet. Tracks and Library are complete and readable today.
Access
What you can read without an account
The opening of every course is free. Building RAG Systems — the longest course here, 23 lessons — is readable end to end with no account at all, and every other course opens its first two lessons in full. The lessons past that need a free account.
A free account exists for the things that have to persist, not to unlock the words: your place in a course, completed lessons, streaks, and bits. Nothing in Stack is behind a payment.
About Nybble™
The AI space moves fast.
Nybble™ is how you keep up — and stay sharp.
What happened. In two minutes.
The AI news cycle moves at a pace no one can keep up with. Snack distills what launched, what shipped, and what matters — every day, without the filler.
Go to SnackThe concepts behind the headlines.
News tells you what. Stack tells you why and how. From RAG architectures to agentic evals, these are the ideas that will shape what you build next.
Go to StackProve you actually get it.
Reading about LangChain is not the same as knowing it. Hack challenges you with production-grade questions, then shows you the references that make the answer stick.
Go to Hack