The Transformer Architecture: What Practitioners Actually Need to Know

By C.W. Jameson · Published 15 January 2026 · Last reviewed 15 January 2026

The transformer is not magic. It is a very well-designed function approximator with three specific properties that make it scale. Understanding those three properties explains most model behaviour operators observe.

Not the math — the mental model. How attention works, why it scales, and what architectural decisions affect output quality.