JavaScript, TypeScript & Technical Interviewing
Practical guides, interview question breakdowns, code review exercises, and hiring frameworks for software engineers and hiring managers.
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JavaScript
In-depth resources on JavaScript mechanics, event loop, closures, async patterns, and core algorithms.
TypeScript
Master TypeScript type inference, discriminated unions, generic utility types, and live coding exercises.
Coding Interviews
Best practices, problem lists, and scorecards for running zero-friction live coding interviews.
Technical Interviews
Frameworks for evaluating software engineers, senior backend hiring, and building repeatable interview processes.
Code Review
How to conduct realistic code review interviews that test code quality, security, performance, and architecture.
Featured Guides
JavaScript Interview Questions: 25 Questions You Should Know
Master the 25 essential JavaScript interview questions covering primitives, closures, event loop, promises, prototypes, and memory leaks with runnable code examples.
TypeScript Interview Questions and Type System Guide
Core TypeScript interview questions covering interfaces, type aliases, generics, utility types, discriminated unions, and type guards.
Live Coding Interviews: A Practical Guide for Interviewers
Learn how to conduct effective, fair live coding interviews. Includes problem selection criteria, hint strategies, candidate scorecards, and remote interview tips.
Senior Backend Interview Questions for Engineering Managers
High-signal interview questions for senior backend engineers covering databases, API design, caching, queues, concurrency, and distributed-system trade-offs.
Code Review Interviews: How to Run One and What to Evaluate
Learn why code review interviews are superior to abstract puzzle interviews. Step-by-step guide to designing exercises, candidate scorecards, and realistic pull request evaluations.
Latest Articles
System Design: API Rate Limiting Algorithms, Distributed Architecture & Implementation
Deep dive into API rate limiting for system design interviews: Token Bucket, Leaky Bucket, Sliding Window, Redis Lua scripts, HTTP 429 headers, and resolving the Noisy Tenant problem.
Circuit Breaker Pattern in Node.js & Microservices: Architecture, States & Implementation
Master the Circuit Breaker pattern for senior backend and system design interviews. Learn Closed, Open, and Half-Open state machines, rolling window metrics, and fallback strategies.
Mastering AbortController in JavaScript: Clean Cancellation, Timeouts & Async Patterns
Complete guide to AbortController and AbortSignal in modern JavaScript. Learn request cancellation, AbortSignal.timeout, race condition prevention, and memory leak cleanup.
Backend Code Review Interview: API, Database & Security Exercises
Practical backend code review interview questions for API handlers, database access, authorization, async work, and reliability. Includes a scoring rubric and live JavaScript and TypeScript exercises.
Code Review Interview vs Algorithm Interview: Which to Use?
Compare code review and algorithm interviews by the signal they provide, the roles they fit, and how to combine them without creating an unfair or exhausting interview loop.
JavaScript Promise Combinators: Promise.all, allSettled, race & any Explained
Master JavaScript Promise combinators for technical interviews. Detailed comparison of Promise.all, Promise.allSettled, Promise.race, and Promise.any with runnable code examples.
JavaScript Event Loop Demystified: Call Stack, Microtasks & Macrotasks
Deep dive into the JavaScript Event Loop, Call Stack, Microtask Queue, and Macrotask Queue. Trace execution order with interactive code output exercises.
JavaScript Prototype Chain & Prototypal Inheritance Interview Guide
Understand JavaScript prototypes, prototypal inheritance, Object.create, class syntax transpilation, and prototype chain lookups for technical interviews.
TypeScript Type Narrowing & Discriminated Unions: Interview Questions & Code
Master TypeScript type narrowing techniques, discriminated unions, type guards (typeof, instanceof, in, is), and exhaustiveness checking using never.
Mastering TypeScript Utility Types: Partial, Required, Readonly, Record, Pick, Omit & Exclude
Comprehensive guide to TypeScript built-in utility types and implementing custom dynamic types from scratch in live coding interviews.
Frontend Coding Interview Guide: DOM Manipulation, Async Utilities & State Management
Complete guide to frontend coding interviews. Learn how interviewers evaluate candidate skills across DOM manipulation, custom event emitters, debounce, and state management.
How to Build an Async Concurrency Limiter (Task Pool) in JavaScript
Step-by-step guide to implementing an async concurrency limiter (promise pool) in JavaScript with clean code, queue execution, and optimal time complexity.
How to Conduct Effective Live Coding Interviews: Best Practices & Scorecard
A comprehensive guide for engineering managers and interviewers on designing, scoring, and conducting practical live coding interviews that candidates love.
React Code Review Interview: Stale Closures in useEffect
Practice identifying a stale closure and missing hook dependency in a focused React useEffect code review example.
TypeScript Code Review Best Practices: Catching Any Types, Unsafe Casts & Mutability Bugs
A comprehensive code review checklist for evaluating TypeScript pull requests. Learn how to spot unsafe type assertions, hidden any types, and missing error handling.
JavaScript Interview Questions: 25 Questions You Should Know
Master the 25 essential JavaScript interview questions covering primitives, closures, event loop, promises, prototypes, and memory leaks with runnable code examples.
JavaScript Coding Interview: What to Expect and How to Prepare
A comprehensive guide to JavaScript coding interviews. Learn how interviewers evaluate candidates across algorithms, async utility building, code quality, and live communication.
Key JavaScript Async Interview Questions
Deep dive into asynchronous JavaScript interview questions covering the event loop, Promises, async/await, Promise.all, race conditions, and AbortController.
JavaScript Closures Explained for Coding Interviews
Understand JavaScript closures, lexical scope, private state, factory functions, loop gotchas, and memory considerations with step-by-step interview exercises.
JavaScript Array Interview Questions and Practice Problems
Practice essential JavaScript array coding problems, including Two Sum, flattening, deduplication, chunking, and custom array utilities.
TypeScript Interview Questions and Type System Guide
Core TypeScript interview questions covering interfaces, type aliases, generics, utility types, discriminated unions, and type guards.
TypeScript Coding Interview: 4 Problems to Practice
Four practical TypeScript coding interview exercises with solutions, including a typed event emitter, Result type, DeepReadonly, and a code review challenge.
TypeScript Generics: Interview Questions and Practical Examples
Master TypeScript generics for technical interviews. Learn generic constraints, keyof lookups, inference, conditional types, and common generic utility implementations.
Live Coding Interviews: A Practical Guide for Interviewers
Learn how to conduct effective, fair live coding interviews. Includes problem selection criteria, hint strategies, candidate scorecards, and remote interview tips.
Coding Interview Problems for JavaScript Developers
A curated set of practical coding interview problems covering arrays, strings, hash maps, promises, stacks, and code review.
Technical Interview Questions: How to Evaluate Software Engineers
A comprehensive framework for evaluating software engineers across problem solving, system architecture, code quality, and debugging skill.
Senior Backend Interview Questions for Engineering Managers
High-signal interview questions for senior backend engineers covering databases, API design, caching, queues, concurrency, and distributed-system trade-offs.
Code Review Interviews: How to Run One and What to Evaluate
Learn why code review interviews are superior to abstract puzzle interviews. Step-by-step guide to designing exercises, candidate scorecards, and realistic pull request evaluations.
Code Review Interview Questions and Exercises
Realistic code review interview scenarios covering N+1 queries, race conditions, memory leaks, unhandled promises, authorization bugs, and weak TypeScript design.
Remote Coding Interviews: How to Run Better Technical Interviews
Best practices for conducting remote technical interviews. How to select lightweight coding environments, eliminate sign-up friction, and evaluate candidates fairly.
Practice & Conduct Live Technical Interviews
Pairlet provides no-signup live coding interview rooms with real-time code collaboration, Monaco editor, and browser-based execution.