You now know how to design an autocomplete.
Architecture: Input + SuggestionList with composable rendering.
Performance: Debounce input (ms). Cache results. Cancel stale requests.
Interactions: Full keyboard navigation. Highlight matches visually.
Accessibility: Combobox pattern with aria-activedescendant.
Data: Client-side for small datasets, server-side for large.
Interview tip: Mention debouncing, race conditions, and accessibility early. These differentiate senior candidates.