[{"_1":2,"_3":-5,"_4":-5},"loaderData",{"_5":6,"_7":8},"actionData","errors","root",{"_28":-5,"_38":-5,"_39":40,"_41":42,"_43":44,"_45":46,"_47":48,"_49":50,"_51":52,"_53":54,"_55":56,"_57":58},"routes/_store+/_readers+/email_author.$slug/route",{"_9":10,"_11":-5},"book",{"_12":13,"_14":15,"_16":17,"_18":19,"_20":21,"_22":23},"currentUser","id","Z2lkOi8vbGVhbnB1Yi9TdG9yZTo6Qm9va1Byb2R1Y3QvNzkwNjY","title","Under The Hood","state","published","contactAuthorMethod","email","aboutText","

Most LLM books teach you to *use* models. This one teaches you to *build* them — every layer, every optimizer step, every cache, every quantization scheme — and then to deliberately break each piece so you understand why it exists in the first place.

It is a workshop in book form. 35 hands-on projects, ~250,000 words, one tight spiral that takes you from a single autograd scalar all the way to fusing independently trained specialists into a routed system. No black boxes. No \"import library, call method.\" You write the code, you run it, you break it, you measure what broke.

Each project follows the same disciplined rhythm: Hook → The Concept → Why It Matters → The Build → **BREAK IT** → Optional Homework → Questions To Answer → Go Further → What You Now Know. Reading the book without breaking the code is half the experience. The breaks are where the lessons actually live.

A public code companion lives at github.com/mechramc/Under-the-hood with runnable build.py, tests, and captured outputs for every project.

If you have ever read a transformer paper and felt that the diagram and the code were in two different universes — this book closes that gap.

**Build it. Break it. Measure it.**

","authors",[24],{"_12":25,"_26":27,"_28":29},"Z2lkOi8vbGVhbnB1Yi9TdG9yZTo6UHJvZHVjdEF1dGhvci84NDY0MA","name","Ramchand Kumaresan","user",{"_30":31},"avatar",{"_32":33,"_34":35,"_36":37},"url","https://d39qdlcrvnra4b.cloudfront.net/avatars/3726808/medium/avatar.jpg?1779391006","styleName","medium","exists",true,"shoppingCartId","shoppingCart",{"_12":71,"_72":73,"_74":37,"_75":76,"_77":78,"_79":80,"_81":37},"locale","en","readerTheme","light","constants",{"_69":70},"publishers",{"_65":66,"_67":68},"learnerOrganizations",[],"needsLocaleCookieSync",false,"announcements",{"_59":60,"_61":-5},"sentryEnvironment","production","sentryRelease","cce21d19a0d9612afdbced29947de1d8868e588b","announcement_store",{"_62":52,"_63":64},"announcement_authors","flag","text","

Kick off your book project, get started with GhostAI, get better at marketing, or spend the day doing all three! Free live workshops on Zoom. Saturday, June 27, 2026.

\n","companies",[],"universities",[],"paypalClientId","AX53Cwz8jR6rVVzzZiZNWWXl0dGagi-GZrjG-S3Ua14E5nrKMn7DxDQ730O4R8LusLPp49ALn6aRVaEy","no-cart","count",0,"free","updatedAt","","paymentGateway","STRIPE","cartItems",[],"loading"]

Email the Author