Learn

Tech interview concepts, explained

Short, focused articles on the concepts behind tech interview questions — the traps interviewers actually probe, with worked examples. See all topics we cover.

LanguageAll English Español

ConceptAll Python JavaScript React AI SQL Cloud React Native Databases Testing & QA Performance+248 more — search below

Testing FrameworksEN
When to use testing frameworks (and when not to)
Navigating the complexities of testing frameworks can enhance your development process and improve software quality.
OAuthEN
OAuth: Enhancing Security Without Compromising User Experience
Learn how to optimize OAuth implementations for security and user experience—key insights for interviews and real-world applications.
AuthenticationEN
Authentication — the hidden risks of weak passwords and MFA
Strengthen your authentication strategies by addressing weak passwords and multi-factor authentication pitfalls before they compromise your application.
SOAPEN
SOAP — the pitfalls of overly strict contracts in APIs
Understanding the intricacies of SOAP can prevent integration failures and improve system reliability in production.
GoEN
When to use Go (and when not to)
Learn when Go's concurrency and performance make it ideal for scenarios—and when it might not be the best fit.
Data WarehousingEN
When to use Data Warehousing (and when not to)
Master when to choose a data warehouse and recognize pitfalls that can impact performance and scalability in your projects.
XMLEN
XML interview questions: common mistakes and pitfalls
Learn key insights into XML, explore common interview traps, and understand how it impacts real-world applications in development.
Saga PatternEN
When to use Saga Pattern (and when not to)
Uncover the Saga Pattern's benefits and trade-offs in distributed systems to navigate technical interviews and real-world applications.
Infrastructure as CodeEN
Infrastructure as Code interview questions: avoiding common pitfalls in production
Master Infrastructure as Code concepts and tackle common interview traps to excel in your technical career.
FirebaseEN
Firebase — the silent pitfalls of choosing Realtime Database vs Firestore
Understanding when to choose Firestore or Realtime Database can prevent performance issues in high-scale applications using Firebase.
IndexingEN
When to use indexing (and when not to)
Understand the nuances of indexing to optimize database queries and avoid common pitfalls in interviews and production environments.
Web ServicesEN
Web Services interview questions and common mistakes — avoiding REST vs SOAP pitfalls
Master the nuances between REST and SOAP to avoid common pitfalls in interviews and production environments.
AuthorizationEN
Authorization common mistakes that trip up candidates
Misunderstanding authorization can lead to critical security flaws in applications, especially in multi-tenant environments.
State ManagementEN
State Management — avoiding performance pitfalls in React
Learn state management strategies in React to optimize performance and avoid common pitfalls during development and in interviews.
JiraEN
When to use Jira (and when not to)
Master the nuances of using Jira effectively in Agile teams, avoiding common pitfalls.
UI OptimizationEN
UI Optimization: The Rendering Pitfalls That Slow You Down
Mastering UI optimization techniques can greatly enhance application performance and user experience.
Trade-offsEN
Trade-offs: the hidden costs of architectural decisions
Understanding architectural trade-offs is crucial for making informed development decisions and passing technical interviews.
HTTP Status CodesEN
When to use HTTP Status Codes (and when not to)
Mastering HTTP status codes is essential for building robust APIs and ensuring clear client-server communication.
Test AutomationEN
Test Automation — the flaky test that halts the pipeline
Flaky tests can undermine automation efforts, leading to delays and confusion. Learn to identify and manage them effectively.
RenderingEN
Rendering — the performance pitfall of excessive re-renders
Avoid excessive re-renders in React applications to enhance performance and prevent rendering issues.
ACIDEN
ACID transactions: Why you might choose SQL over NoSQL
Understanding ACID guarantees helps ensure data integrity and reliability in transactional systems, crucial for interviews and production environments.
React Performance OptimizationEN
React Performance Optimization: Tuning React for Real-World Efficiency
Mastering performance optimization in React can significantly enhance application efficiency and user experience.
Atomic Design PrinciplesEN
Atomic Design Principles: Building Scalable UI Systems
Master Atomic Design Principles to craft maintainable UI components and ace your next interview.
React Context PerformanceEN
React Context Performance: Common Mistakes in Large Applications
Understanding React Context performance pitfalls helps prevent render issues in large applications, leading to efficient code during development.

Tech interview concepts, explained

When to use testing frameworks (and when not to)

OAuth: Enhancing Security Without Compromising User Experience

Authentication — the hidden risks of weak passwords and MFA

SOAP — the pitfalls of overly strict contracts in APIs

When to use Go (and when not to)

When to use Data Warehousing (and when not to)

XML interview questions: common mistakes and pitfalls

When to use Saga Pattern (and when not to)

Infrastructure as Code interview questions: avoiding common pitfalls in production

Firebase — the silent pitfalls of choosing Realtime Database vs Firestore

When to use indexing (and when not to)

Web Services interview questions and common mistakes — avoiding REST vs SOAP pitfalls

Authorization common mistakes that trip up candidates

State Management — avoiding performance pitfalls in React

When to use Jira (and when not to)

UI Optimization: The Rendering Pitfalls That Slow You Down

Trade-offs: the hidden costs of architectural decisions

When to use HTTP Status Codes (and when not to)

Test Automation — the flaky test that halts the pipeline

Rendering — the performance pitfall of excessive re-renders

ACID transactions: Why you might choose SQL over NoSQL

React Performance Optimization: Tuning React for Real-World Efficiency

Atomic Design Principles: Building Scalable UI Systems

React Context Performance: Common Mistakes in Large Applications