Machine Coding
Build UI components â star rating, autocomplete, kanban, infinite scroll
Hatchling
Intermediate
Build a Star Rating Component
A star rating tests DOM manipulation, event handling, accessibility, and component state management. Interviewers look for hover preview, keyboard support, and half-star precision.
Build a Todo List with Full CRUD
The Todo list sounds simple but interviewers use it to test state management patterns, data persistence, filtering, and clean component architecture.
Build Tic-Tac-Toe
Tic-tac-toe tests state modeling, win detection algorithms, turn management, and component decomposition. Interviewers often extend it with AI opponents or variable board sizes.
Build a Progress Bar with Controls
A progress bar with start, pause, stop, and restart tests timer management, CSS transitions vs JS animation, and the requestAnimationFrame API.
Dinosaur
Advanced
Build an Autocomplete / Typeahead Search
Autocomplete combines debouncing, async data fetching, keyboard navigation, caching, and accessibility. It's one of the most comprehensive machine coding questions.
Build Infinite Scroll
Infinite scroll tests Intersection Observer, pagination state, loading states, scroll restoration, and performance with large lists. A staple machine coding question.
Apex
Architect