xavier-ramirez.com
STAGE 0 · THE BACKBONE

How an LLM is built, end to end.

Follow the pipeline from raw web text to a served answer — nine stations, left to right. Set how deep you want to go, and each station reveals the right lessons.

HOW DEEP?
11 lessons in this path

FundamentalsThe plain idea — what it is and why it exists.

02

Filter

1 / 7

Clean it and build the training set.

FQuality filtering & heuristicsWhy ~90% of the web is thrown out.Live
04

Transformer

1 / 5

The forward pass through the hidden layers.

FWhat a transformer block doesAttention, in plain words.Live