JavaScript fundamentals, and the agent workflows built on top of them.

Track 01 · 30 lessons

Foundations

The syntax and the mental model. Short, runnable, no fluff.

Runnable exercises

Track 02 · 4 lessons

AI-Native JavaScript

Configuring agents, harnesses and feedback loops for this language. Updated as the tooling moves.

New

Track 03 · 4 lessons

Review & Verify

How generated code fails in this language, and the checks that catch it before your users do.

New

AI-Native

Setting up a coding agent for a JavaScript project

Node projects have the loosest defaults of any ecosystem here, which means the setup work matters more.

AI-Native

Writing an AGENTS.md for JavaScript

JavaScript needs a longer instructions file than the typed languages, and most of the extra length should be one list: what the platform now does that a package used to.

AI-Native

Testing JavaScript that calls a language model

Your function is now non-deterministic, slow, costs money per call, and streams. Here is a test strategy that still works — including for the streaming part, which is where most of the real bugs are.

Hello, World!

Welcome to the first tutorial. In this tutorial you will learn how to write your first line of code. JavaScript is a very powerful language.

Variables and Types

JavaScript is dynamically typed, so a variable can hold any value. Declare with const by default, let when you need to reassign.

Arrays

JavaScript can hold an array of variables in an Array object. In JavaScript, an array also functions as a list, a stack or a queue.

Manipulating Arrays

Arrays can also function as a stack. The push and pop methods insert and remove variables from the end of an array.

Operators

Every variable in JavaScript is casted automatically so any operator between two variables will always give some kind of result.

Conditions

The if statement allows us to check if an expression is equal to true or false, and execute different code according to the result.