Revision Sheet
Async Control
async and await are promise syntax. They improve readability, but concurrency, errors, cancellation, and cleanup still need deliberate design.
Loading Boundaries
Tasks, microtasks, rendering order, ES modules, and dynamic imports all affect how fast an interface becomes usable.
Advanced Objects
Proxy, Reflect, WeakMap, WeakSet, and weak references are powerful tools for frameworks, metadata, and memory-sensitive behavior.