Promises & async

What you'll learn

• Why promises replaced callbacks, and what they really are
• Chaining, error handling, and finally
• async / await as syntactic sugar — with caveats
• Parallel vs sequential, and the right Promise.* method
• Microtasks, the event loop, and surprising orderings
• Patterns for cancellation and timeouts

1. 01
   Why callbacks weren't enough

   The pyramid, error handling, and inversion of control.
   11 min
2. 02
   What a promise is

   A value with a state. Pending, fulfilled, rejected.
   13 min
3. 03
   then, catch, finally

   Chaining and the rules promises actually follow.
   14 min
4. 04
   async / await

   The same promises, written like procedures.
   15 min
5. 05
   Parallel vs sequential

   Promise.all, allSettled, race — and when each is wrong.
   14 min
6. 06
   Errors in async code

   try/catch, unhandled rejections, and the patterns that survive.
   14 min
7. 07
   Microtasks and the event loop

   Why the order of your logs sometimes lies.
   16 min