Frontend Engineer Interview Questions

Showing 1–21 of 21 results

• AirwallexMedium·Frontend Engineer
  Name-Keyed Async Task Scheduler with Sequential Lanes, Cancel and Clear by Name

  Implement a JavaScript task scheduler for async functions where tasks sharing a name run strictly in order while tasks with different names run concurrently. Follow-ups add cancelling the running task for a name and clearing every running and queued task by name, testing promise handling, race conditions and API design.

  Software Engineering FundamentalsTechnical Screen
• AmazonMedium·Frontend Engineer
  Implement an Accessible Autocomplete Search Component

  Design and implement an accessible, race-condition-resilient autocomplete search component in React or modern JavaScript, focusing on debounced queries, ARIA combobox semantics, and keyboard navigation.

  Software Engineering FundamentalsTechnical ScreenReactAccessibilityFrontend
• AppleMedium·Frontend Engineer
  Build an Accessible Recursive Expand-and-Collapse Tree in React

  This problem tests recursive component design in React, state management for nested data structures, and the implementation of WAI-ARIA standards for accessible UI components.

  Software Engineering FundamentalsTechnical ScreenReactFrontendAccessibility
• AppleMedium·Frontend Engineer
  Diagnose Cold-Load and Massive-Table Performance in a Web App

  This problem tests your understanding of critical path rendering optimization for cold loads and memory management strategies for handling massive datasets in a browser environment.

  Software Engineering FundamentalsTechnical ScreenPerformanceDOMReact
• AppleMedium·Frontend Engineer
  Explain JavaScript Scope, Closures, Timers, and the Event Loop

  Tests deep understanding of the JavaScript runtime, specifically lexical scope, closures, the distinction between task and microtask queues in the event loop, and browser script loading mechanics.

  Software Engineering FundamentalsTechnical ScreenJavaScriptEvent LoopClosures
• AtlassianHard·Frontend Engineer
  Build a 2x3 React Feed Grid from Static Data, Then from an API, and Explain Your Hooks

  A front-end coding exercise: show feed items with an id, text and creation time in a two-row, three-column React grid, first from static data and then from a provided API. It tests CSS grid layout, data fetching with loading and error states, effect cleanup, and how clearly the candidate explains the React hooks they use.

  Software Engineering FundamentalsTechnical Screen
• AtlassianMedium·Frontend Engineer
  Build a Social Feed List in HTML/CSS, Then Render It from a Mock API

  A two-stage front-end coding exercise: build a Twitter-style social feed list with HTML and CSS, then render it from a mock API. It tests semantic markup, a resilient card layout, asynchronous loading with loading and error states, and safe rendering of user-generated text.

  Software Engineering FundamentalsTechnical Screen
• CCensysMedium·Frontend Engineer
  Add Case-Insensitive Search to a Support Ticket Queue UI and Debug Its Behavior

  A frontend exercise on an existing support ticket queue with Unresolved and Archived tabs, a ticket list and an activity panel: make the search box filter tickets by title or assignee regardless of letter case, then debug parts of the app that misbehave. It tests reading unfamiliar code, state design and systematic debugging.

  Software Engineering FundamentalsTechnical Screen
• CitadelEasy·Frontend Engineer
  Build a Real-Time Event Feed Dashboard

  Implement a robust React hook to manage a high-frequency, real-time event feed dashboard with pause/resume controls, out-of-order de-duplication, memory bounding, and rolling time-window statistics.

  Software Engineering FundamentalsTechnical Screenreacttypescriptsliding-window
• HarveyMedium·Frontend Engineer
  Build a Virtualized React Spreadsheet with Cell Formulas

  Design and implement a virtualized React spreadsheet component supporting editable cells, formula evaluation with string concatenation, cycle detection, and targeted re-rendering.

  Software Engineering FundamentalsTechnical ScreenReactVirtualizationGraph Algorithms
• Jane StreetMedium·Frontend Engineer
  Build a Web Calculator That Matches a Reference App

  This question evaluates frontend engineering competencies—interactive UI implementation, state management, event-driven logic, and visual layout fidelity—within the domain of software engineering fundamentals and web frontend development.

  Software Engineering FundamentalsTechnical Screen
• MMomentMedium·Frontend Engineer
  Build a Race-Free Memory Card Game in React

  Work through the state and timing logic for a React memory-card game that remains correct under rapid clicks and restarts. The exercise examines stale closures, input locking, timeout cleanup, stable card identity, accessible interaction, and tests for race-prone transitions.

  Software Engineering FundamentalsTechnical Screen
• OktaMedium·Frontend Engineer
  Review Code for Memory Risks

  This question tests your ability to identify memory-intensive patterns and performance bottlenecks in JavaScript array manipulation, specifically regarding garbage collection and object reference stability.

  Software Engineering FundamentalsTechnical ScreenJavaScriptComplexity AnalysisMemory Management
• RobinhoodMedium·Frontend Engineer
  Build a Chainable Rectangle Manipulation API

  This problem tests your ability to design a fluent interface (method chaining) that manages an internal queue of asynchronous operations to ensure tasks execute sequentially.

  Software Engineering FundamentalsTechnical ScreenJavaScriptFluent-APIAsync
• RobloxHard·Frontend Engineer
  Build a Configurable Two-Player Tic-Tac-Toe Board in React

  Tests your ability to architect a scalable, accessible React component with dynamic state, efficient win-detection logic for large grid sizes, and robust handling of prop updates.

  Software Engineering FundamentalsTechnical ScreenReactFrontendState Management
• SnowflakeMedium·Frontend Engineer
  Build an Arrow-Controlled Kanban Board in React

  Design and implement a performant React Kanban board in TypeScript with normalized state and accessible arrow controls for shifting tasks across ordered columns at scale.

  Software Engineering FundamentalsTechnical Screenreacttypescriptfrontend
• SnowflakeMedium·Frontend Engineer
  Explain React classes, lifecycle, and hooks

  This question assesses the evolution of React component patterns, specifically focusing on the transition from class-based lifecycles to functional hooks, and the management of stateful side effects.

  Software Engineering FundamentalsTechnical ScreenReactFrontendJavaScript
• TTomaEasy·Frontend Engineer
  Identify the CSS color function

  This question evaluates a candidate's understanding of CSS color functions, specifically knowledge of channel-based color specification and the use of an optional opacity component.

  Software Engineering FundamentalsTechnical Screen
• TTomaEasy·Frontend Engineer
  Which CSS function supports opacity?

  This question tests your knowledge of modern CSS color syntax and the various ways to define transparency within style rules.

  Software Engineering FundamentalsTechnical ScreenCSSFrontendStyling
• VerkadaMedium·Frontend Engineer
  Implement a Camera List UI from a Defined Visual Contract

  Implement a responsive React camera-card list with fixed preview ratios, status and missing-image states, semantic selection, and a clear visual-verification method.

  Software Engineering FundamentalsTechnical Screen
• WaymoMedium·Frontend Engineer
  Build a React naval board

  This question evaluates a candidate's ability to design frontend state and UI logic—specifically React component structure, state management, click-handling semantics, and derived sunk-detection logic for a Battleship-style board.

  Software Engineering FundamentalsTechnical Screen