System Design Interview: Designing a Chat Application
Real-time messaging is one of the most demanding system design problems because it combines persistent connections, low-latency delivery, message ordering,...
System Design Interview: Designing a URL Shortener
The URL shortener is one of the most common system design interview questions, and for good reason. It sounds deceptively...
Two-Factor Authentication (2FA) Implementation Guide
Passwords alone no longer provide adequate protection for user accounts. Credential stuffing attacks, phishing, and database breaches make single-factor authentication...
Secrets in Code: How to Detect and Prevent Leaked Credentials
Hardcoded secrets in code are one of the most common and preventable security vulnerabilities. API keys, database passwords, private tokens,...
Dependency Vulnerability Scanning with Snyk and Dependabot
Every modern application depends on hundreds of third-party packages. Each package is a potential entry point for attackers when known...
Content Security Policy (CSP) Headers Explained
Content Security Policy (CSP) is one of the most powerful browser security mechanisms available to web developers. It tells the...
Secure Password Storage: bcrypt, Argon2, and Best Practices
Storing passwords correctly is one of the most critical security decisions you will make in any application that handles user...
API Security Checklist for Production Applications
This API security checklist covers the essential protections every production API needs before handling real user traffic. Use it as...
CORS Explained: Configuration and Common Mistakes
If you have built a web application that calls an API on a different domain, you have almost certainly encountered...