Starting out
What Node actually is, how to run a file, and how to read the error you are certainly about to get.
3 of 3 written
Node.js, from zero
JavaScript on your own machine, from the first console.log to a program you can ship, and every line of output on every page really ran.
Where this stands
50 of 50 lessons written. The bar on every card below is counted from the lesson files that exist, not from a number I typed. A lesson that is planned and unwritten says so on its own page too.
- 355 Node panels, every one executed by Node v26.7.0 during this build
- 121 of those also run in this page, each checked to print exactly what Node printed
- 43 terminal sessions, 134 real commands with their real exit codes
- 552 checks, all passing, or this build would have refused to write
- 72 panels that die on purpose, across 26 distinct error names and codes, each showing what Node really printed
- 8 listings shown but not run, each stating why on the panel itself
- No network, and no npm dependencies: npm itself is pointed at an address nothing answers on
The language
Values, numbers, text, and the equality rules JavaScript is famous for, run for real rather than memorised.
5 of 5 written
Functions
Parameters, closures, this, and functions as values: the machinery underneath every callback in the rest of the course.
4 of 4 written
Data structures
Arrays, objects, Map and Set, and the copying and aliasing rules that decide whether your data changes under you.
4 of 4 written
Classes and errors
Prototypes and the classes built on them, errors you throw on purpose, and the iteration protocol behind every for...of.
3 of 3 written
Modules and npm
How a program becomes more than one file, the two module systems Node has to live with, and what npm actually does to your folder.
4 of 4 written
Asynchronous Node
Callbacks, the event loop measured rather than drawn, promises, async/await, and what happens to an error nobody catches.
5 of 5 written
Files and the process
Reading and writing real files, bytes and encodings, and the process your program runs as: its arguments, environment, exit code and signals.
4 of 4 written
Events and streams
The EventEmitter under almost everything in Node, streams, and backpressure: how to process a file bigger than your memory.
3 of 3 written
HTTP
A web server from nothing, a JSON API with no framework, and fetch -- every request on these pages really sent, to a server the panel started itself.
3 of 3 written
Data and security
The SQLite database built into Node, and the injection, traversal and permission mistakes that turn a working program into a vulnerable one.
2 of 2 written
Testing
Proving your code does what you claim, with the test runner that ships in Node.
2 of 2 written
Performance
What blocking the event loop actually costs, threads for work that computes, and measuring speed and memory instead of guessing.
4 of 4 written
Production
TypeScript with no build step, and the configuration, logging and shutdown habits that separate a script from a service.
2 of 2 written
Shipping it
Turning a folder into a package someone else can install, and one project built, tested and shipped end to end.
2 of 2 written