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Interview Questions

Practice real technical interview questions. Filter by difficulty, type, or category.

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Showing 1–20 of 28 questions

#Category
1Machine Coding: Build a Smart Task Scheduler with CooldownFrontend EngineeringMediumJavaScript27
Machine Coding: Build a Smart Task Scheduler with CooldownMedium
Frontend EngineeringJavaScript27
2useUpdateEffect()Frontend EngineeringMediumJavaScript14
useUpdateEffect()Medium
Frontend EngineeringJavaScript14
3Mastering the useFocus Hook: From React Fundamentals to Production-Grade ArchitectureFrontend EngineeringMediumJavaScript4
Mastering the useFocus Hook: From React Fundamentals to Production-Grade ArchitectureMedium
Frontend EngineeringJavaScript4
4useArray()Frontend EngineeringMediumJavaScript3
useArray()Medium
Frontend EngineeringJavaScript3
5useTimeout()Frontend EngineeringMediumJavaScript11
useTimeout()Medium
Frontend EngineeringJavaScript11
6Your Invoice Generator Must Format Currency Amounts With Thousands SeparatorsFrontend EngineeringMediumJavaScript8
Your Invoice Generator Must Format Currency Amounts With Thousands SeparatorsMedium
Frontend EngineeringJavaScript8
7Your Scientific Calculator Handles Signed Arbitrary-Precision Addition Including NegativesFrontend EngineeringMediumJavaScript2
Your Scientific Calculator Handles Signed Arbitrary-Precision Addition Including NegativesMedium
Frontend EngineeringJavaScript2
8Your Accessibility Audit Tool Needs to Collect All Unique HTML Tag Names in a DocumentFrontend EngineeringMediumJavaScript1
Your Accessibility Audit Tool Needs to Collect All Unique HTML Tag Names in a DocumentMedium
Frontend EngineeringJavaScript1
9Your Search Engine Combines Results From Multiple Pre-Sorted Indexes Into One Ranked ListFrontend EngineeringEasyJavaScript3
Your Search Engine Combines Results From Multiple Pre-Sorted Indexes Into One Ranked ListEasy
Frontend EngineeringJavaScript3
10Build a Query String Parser and Builder for Environments Without Native URLSearchParamsFrontend EngineeringHardJavaScript2
Build a Query String Parser and Builder for Environments Without Native URLSearchParamsHard
Frontend EngineeringJavaScript2
11Your Template Engine Safely Accesses Deeply Nested Config Values Without Crashing on Missing KeysFrontend EngineeringMediumJavaScript0
Your Template Engine Safely Accesses Deeply Nested Config Values Without Crashing on Missing KeysMedium
Frontend EngineeringJavaScript0
12Wrap DOM Event Listeners Into a Subscribable Stream With Automatic CleanupFrontend EngineeringEasyJavaScript6
Wrap DOM Event Listeners Into a Subscribable Stream With Automatic CleanupEasy
Frontend EngineeringJavaScript6
13Your Polling Service Needs a Controllable Repeating Timer With Start, Pause, and StopFrontend EngineeringMediumJavaScript2
Your Polling Service Needs a Controllable Repeating Timer With Start, Pause, and StopMedium
Frontend EngineeringJavaScript2
14The "Infinity Ledger" Addition AlgorithmFrontend EngineeringEasyJavaScript1
The "Infinity Ledger" Addition AlgorithmEasy
Frontend EngineeringJavaScript1
15Build an Asynchronous Value Container That Chains Handlers and Propagates ErrorsFrontend EngineeringMediumJavaScript2
Build an Asynchronous Value Container That Chains Handlers and Propagates ErrorsMedium
Frontend EngineeringJavaScript2
16Implement Throttle with Configurable Leading and TrailingFrontend EngineeringMediumJavaScript34
Implement Throttle with Configurable Leading and TrailingMedium
Frontend EngineeringJavaScript34
17Implement Throttle with Trailing EdgeFrontend EngineeringMediumJavaScript61
Implement Throttle with Trailing EdgeMedium
Frontend EngineeringJavaScript61
18Design a Rate Limiter: Throttle vs Debounce Decision FrameworkFrontend EngineeringHardJavaScript41
Design a Rate Limiter: Throttle vs Debounce Decision FrameworkHard
Frontend EngineeringJavaScript41
19Implement Throttle with Cancel and FlushFrontend EngineeringHardJavaScript51
Implement Throttle with Cancel and FlushHard
Frontend EngineeringJavaScript51
20Implement Throttle with Leading EdgeFrontend EngineeringMediumJavaScript50
Implement Throttle with Leading EdgeMedium
Frontend EngineeringJavaScript50

Showing 1–20 of 28 questions