Katkat

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Frontend Engineer Interview Questions

Practice 9403 coding, system design and machine learning questions from 546 companies, sorted by role, topic and interview round. Every question has step-by-step hints, a code runner that supports 8 languages and an AI mentor; members also get the full solution walkthrough.

9403
Questions
546
Companies
11
Topics
8
Languages

Showing 1–12 of 12 results

  • CohereMediumFrontend Engineer
    Design a Real-Time Comment System Front End With Optimistic Updates

    Front-end system design for a real-time comment feed, centered on optimistic updates: a new comment is appended to the list before the backend confirms it, so the user can keep typing. It tests client state modeling, reconciliation with live echoes, failure and retry handling, ordering, reconnection and rendering performance.

    System DesignOnsite
  • CoinbaseHardFrontend Engineer
    Design Frontend Architecture for Trading UI

    This question evaluates competency in frontend architecture for real-time trading UIs, covering state management, rendering strategies, real-time data flow, performance, reliability, security, testing, and observability.

    System DesignOnsite
  • DatabricksMediumFrontend Engineer
    Design a Collaborative Playlist Editor

    Tests your ability to architect a real-time collaborative frontend application, focusing on client-side state synchronization, deterministic list ordering, idempotent mutation protocols, and graceful network reconnection.

    System DesignOnsiteFrontendReal-TimeData Modeling
  • GleanMediumFrontend Engineer
    Design Real-Time Typeahead for Enterprise Search: History, People, Docs, Apps, Filters

    Design real-time typeahead for an enterprise search product that suggests past searches, people, documents, apps and filters as the user types. Tests client request policy and stale-response handling, accessible combobox UI, permission-aware backend fan-out, blending across sources and latency budgets.

    System DesignOnsite
  • GoogleHardFrontend Engineer
    Design an Embeddable Streaming Chat Interface

    Design an embeddable chat-agent widget with resumable streaming, virtualized history, safe caching, accessibility, and meaningful metrics.

    System DesignOnsite
  • GoogleHardFrontend Engineer
    Visualize More Than One Hundred Million Map Points

    Design a multiresolution map that turns over one hundred million points into cached heat maps and detailed pins without overwhelming the browser.

    System DesignOnsite
  • RobinhoodMediumFrontend Engineer
    Design a Photo Album App

    This question evaluates proficiency in frontend system design, specifically client-side component and data architecture, state management and normalization, real-time synchronization, and large-media upload flows; it sits in the System Design domain with a Frontend Engineer focus and tests practical application of these competencies.

    System DesignOnsite
  • RobloxMediumFrontend Engineer
    Design a Reusable Dropdown Menu Component

    Tests a candidate's ability to architect a production-grade, reusable UI component library element with consideration for flexible API design, accessibility (WAI-ARIA), state management, and large dataset performance.

    System DesignOnsiteFrontend System DesignReactAccessibility
  • WaymoMediumFrontend Engineer
    Design the Frontend for an AI Chat Application

    This question tests the ability to design a performant and resilient frontend architecture for a real-time, state-heavy AI chat interface capable of handling large message trees and network instability.

    System DesignOnsiteFrontendState ManagementWebSockets
  • WaymoMediumFrontend Engineer
    Design the Frontend of an AI Chat Application With Streaming Replies

    Frontend-focused system design for an AI chat application. It covers component structure, conversation and message state, streaming replies, stop and retry, safe rendering of model output, performance on long conversations, accessibility and the backend API contract.

    System DesignOnsite
  • xAIMediumFrontend Engineer
    Design a Collaborative Document Editor

    Design collaborative editing with an explicit operation model, OT or CRDT convergence, durable history, reconnect recovery, access control, and separate presence state.

    System DesignOnsite
  • xAIMediumFrontend Engineer
    Design a Real-Time Collaborative Document Editor with Concurrent Edits

    A system design question for a frontend engineer: design a collaborative document editor where several people edit the same document at once and see each other's changes in near real time. It tests conflict resolution for concurrent edits, client-side state, the sync protocol, persistence and presence.

    System DesignOnsite