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Blog

Learn as you build

Deep dives, security guides, and practical tutorials on the tools developers use every day. Written to save you time.

25articles
7categories
~2min avg read
deep-divesLatest

Mastering Regex Lookahead and Lookbehind

A practical guide to lookahead and lookbehind assertions — the most powerful regex features with real examples.

regexlookaheadlookbehindadvanced
Trong Ngo
February 22, 2026
2 min
Read article
deep-dives

How to Write Efficient Regular Expressions

Regex can be slow — learn how to avoid catastrophic backtracking, optimize your patterns, and use the right tools for the job.

regexperformanceoptimization
Trong Ngo
February 22, 2026·2 min
tutorials

Using Regex for Form Validation: Patterns and Pitfalls

How to use regular expressions for form validation in JavaScript and HTML — with reusable patterns and common mistakes to avoid.

regexvalidationforms
Trong Ngo
February 22, 2026·2 min
tools

10 Regex Patterns Every Developer Should Know

Production-ready regular expressions for email, URL, phone, password, IP address, and more — with explanations.

regexpatternsvalidation
Trong Ngo
February 22, 2026·1 min
tutorials

Regular Expressions 101: A Beginner's Complete Guide

Learn regular expressions from scratch — syntax, anchors, character classes, quantifiers, and groups with practical examples.

regexregular-expressionstutorial
Trong Ngo
February 22, 2026·2 min
tutorials

JavaScript Date API Cheatsheet for Developers

A concise reference for every Date operation you'll need — parsing, formatting, arithmetic, comparison, and timezone handling.

timestampjavascriptdatetime
Trong Ngo
February 22, 2026·2 min
api

Date and Time Best Practices for APIs

How to design time-related API fields correctly — format choices, timezone handling, relative times, and avoiding the most painful datetime bugs.

timestampapi-designdatetime
Trong Ngo
February 22, 2026·1 min
guides

ISO 8601 Date Format: The Standard Every Developer Should Know

A practical guide to the ISO 8601 date/time standard — formats, timezone notation, durations, and how to use it in your APIs.

timestampiso8601datetime
Trong Ngo
February 22, 2026·1 min
tutorials

Handling Timezones in Web Applications

Why timezones are hard, how to avoid the most common bugs, and the right patterns for storing, displaying, and comparing dates.

timestamptimezonesdatetime
Trong Ngo
February 22, 2026·2 min
guides

Unix Timestamps: A Complete Developer's Guide

Everything you need to know about Unix timestamps — what they are, how to work with them in any language, and common pitfalls.

timestampunixdatetime
Trong Ngo
February 22, 2026·2 min
security

Base64 is Not Encryption: Security Misconceptions Explained

Why Base64 offers zero security, common mistakes developers make treating it as obfuscation, and what to use instead.

base64securityencoding
Trong Ngo
February 22, 2026·1 min
encoding

Base64 vs Hex Encoding: Key Differences

When to use Base64 vs hexadecimal encoding — a practical comparison with code examples for hashes, binary data, and cryptographic keys.

base64hexencoding
Trong Ngo
February 22, 2026·2 min
tutorials

Base64 Encoding and Decoding in JavaScript

A complete guide to working with Base64 in JavaScript — browser APIs, Node.js, handling Unicode, and binary data.

base64javascriptnodejs
Trong Ngo
February 22, 2026·1 min
encoding

Base64 in Web Development: Practical Use Cases

Real-world use cases for Base64 in web apps — data URIs, API authentication, file uploads, and inline assets.

base64encodingweb-development
Trong Ngo
February 22, 2026·1 min
encoding

What is Base64 Encoding and How Does It Work?

A clear explanation of Base64 encoding — what it is, why it exists, and how the encoding algorithm works step by step.

base64encodingfundamentals
Trong Ngo
February 22, 2026·2 min
api

The JWT Refresh Token Pattern Explained

How to implement secure, long-lived sessions with short-lived access tokens and refresh tokens — the pattern used by Google, GitHub, and Stripe.

jwtrefresh-tokensauthentication
Trong Ngo
February 22, 2026·2 min
tutorials

Implementing JWT Authentication in Next.js

A step-by-step guide to building JWT authentication in Next.js with App Router, middleware, and secure cookie storage.

jwtnextjsauthentication
Trong Ngo
February 22, 2026·2 min
security

JWT vs Session Tokens: When to Use Each

An honest comparison of JWT and traditional session-based authentication — tradeoffs, use cases, and which one fits your architecture.

jwtsessionsauthentication
Trong Ngo
February 22, 2026·2 min
security

Top JWT Security Vulnerabilities and How to Prevent Them

From algorithm confusion to token theft — learn the most dangerous JWT vulnerabilities and the exact patterns to prevent them.

jwtsecurityvulnerabilities
Trong Ngo
February 22, 2026·2 min
security

Understanding JWT: Structure, Claims, and How It Works

A deep dive into JSON Web Tokens — how they're structured, what claims mean, and why they're the backbone of modern authentication.

jwtauthenticationsecurity
Trong Ngo
February 22, 2026·2 min
deep-dives

JSON vs XML vs YAML vs TOML: When to Use Each

A practical comparison of the four most popular data serialization formats — with real-world use cases for each.

jsonxmlyaml
Trong Ngo
February 22, 2026·2 min
tutorials

JSON Schema Validation: A Complete Guide

Learn how to define, validate, and document your JSON data structures using JSON Schema — the standard for API contracts.

jsonjson-schemavalidation
Trong Ngo
February 22, 2026·2 min
api

JSON Best Practices for REST APIs

Design better APIs with these JSON conventions: naming, pagination, error formats, and versioning patterns used by top tech companies.

jsonrest-apibest-practices
Trong Ngo
February 22, 2026·1 min
tutorials

Common JSON Errors and How to Fix Them

A practical guide to the most frequent JSON parsing errors, what causes them, and exactly how to fix them.

jsondebuggingerrors
Trong Ngo
February 22, 2026·2 min
guides

How to Format and Validate JSON Like a Pro

Learn essential techniques to format, validate, and debug JSON data efficiently — a must-have skill for every developer.

jsonformattingdeveloper-tools
Trong Ngo
February 22, 2026·2 min