Tutorials
Learn by doing
Interactive tutorials on the JavaScript and TypeScript patterns that actually come up in production. Every concept is runnable — edit the examples, break them, see what happens.
JavaScript Async Programming
The complete picture — from synchronous foundations to the Event Loop, Callbacks, Promises, async/await, Generators, and AbortController. Every concept that comes up in production and interviews.
NestJS Architecture Patterns
IoC, DI, GoF patterns applied to real NestJS services. Facade, Adapter, Observer, Strategy — every pattern mapped to a production use case.
Which Array Method to Use When
map vs flatMap, find vs filter, reduce without the headache — a decision framework for the methods you reach for every day.
Higher-Order Functions
Functions that take functions. Closures, currying, and composition — explained through patterns that actually show up in production TypeScript.