Cheat Sheet
| Question | Core Idea | Senior Signal |
|---|---|---|
| Q121 | Timing utilities | Debounce waits for silence; throttle samples over time; rate limits cap total work. |
| Q122 | Memoization | The cache key and invalidation policy are the design. |
| Q123-Q124 | Equality and updates | Objects compare by reference, so structural sharing makes cheap change detection possible. |
| Q125 | Prototype pollution | Never blindly merge untrusted keys into important objects. |