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Problems Lists New Problem Roadmap Interviews Ranking

Problems | Code Master

Problems Lists New Problem Roadmap Interviews Ranking

Community challenges

The problem library

Pick a challenge, write your solution and let the AI judge it in real time.

Difficulty

Language

Topics

310 problems

Problems

310 problems

MediumNewFront-end

Fix Task Board Filters and Counters

Search, Filter & SortForms & Validation+2

Code MasterSolve

HardNewQuest

Subtle Memory Reordering and Hardware Consistency

Code MasterSolve

MediumNewQuest

Garbage Collector Pause Dynamics and Allocation Pressure

Code MasterSolve

MediumNewQuest

SOLID Architectural Trade-offs and Behavioral Reasoning

Data Structure Design

Code MasterSolve

EasyNewQuest

Pure Functions and Side Effects

Code MasterSolve

EasyNewSystem design

Design a Multi-Tenant SaaS Workspace Permission Service

AuthenticationAPI Design+1

Code MasterSolve

EasyNewQuest

Regular Expression Anchors, Quantifiers, and Grouping Fundamentals

String Matching

Code MasterSolve

HardNewSystem design

Design a Real‑Time Video Playback Analytics Service

Real-Time DeliveryStream Processing+1

Code MasterSolve

MediumNewSystem design

Design a Cloud Log Ingestion and Cold Archival Pipeline

Stream ProcessingStorage

Code MasterSolve

MediumNewSystem design

Design a Mobile App Feature Flag and Dynamic Configuration Service

CachingAPI Design+1

Code MasterSolve

MediumFront-end

Fix Data Grid Selection & Batch API Sync Bugs

rubenchirinoSolve

HardFront-end

Accessible Tabbed Workspace with Async Panels and Focus Management

AccessibilityKeyboard Navigation+2

Code MasterSolve

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