Modern JavaScript

What you'll learn

• How modules split a codebase into files that import each other
• What top-level await changes about module loading
• The new Promise utilities and when to reach for them
• Immutable array methods like toSorted and toReversed
• What Symbol and Proxy unlock under the syntax
• How to read the TC39 proposal pipeline so you know what's next

1. 01
   Modules

   How import and export split a program across files — and what type="module" actually changes.
   15 min
2. 02
   Top-level await

   Awaiting at the top of a module — what it lets you do and what it costs the import graph.
   13 min
3. 03
   Promise.withResolvers and friends

   The cleanup of an old pattern — plus the small Promise utilities you can finally stop polyfilling.
   13 min
4. 04
   Array and object additions

   toSorted, toReversed, toSpliced, Object.groupBy, Object.hasOwn, findLast — the methods you'd assume were already there.
   14 min
5. 05
   Symbol and well-known symbols

   Unique opaque keys, the iteration protocol, and why for...of works on some objects but not others.
   15 min
6. 06
   Proxy and Reflect

   Wrapping an object so you can intercept reads and writes — meta-programming in one lesson.
   16 min
7. 07
   What's still moving

   Decorators, Records & Tuples, Temporal beyond basics, and how to read TC39 stages 0 to 4.
   14 min