Blog
Developer Guides
Practical tutorials and references for the tools developers use every day. Every example runs locally in your browser.
Guides
Base64 Encoding: When and Why
Learn what Base64 encoding is, how it works, when to use it, and common misconceptions. Includes examples in JavaScript, Python, and the command line.
Guides
Cron Expression Syntax for Beginners
Learn the five-field Unix cron expression format with practical examples. Covers minutes, hours, days, months, weekdays, and common scheduling patterns.
DevOps
Docker Compose File Reference
A practical guide to writing Docker Compose files. Covers services, networks, volumes, environment variables, health checks, and common patterns.
Guides
How to Format JSON: The Complete Guide
Learn how to format, validate, and minify JSON with examples. Covers syntax rules, common errors, and when to use each format.
Security
JWT Token Structure Explained
Understand the three parts of a JWT token — header, payload, and signature. Learn how JWTs work, when to use them, and common security mistakes.
IoT
MQTT Protocol Guide for IoT
Learn the MQTT protocol for IoT: publish/subscribe messaging, QoS levels, retained messages, and last will. Includes broker setup and practical examples.
Security
Password Security Best Practices for Developers
Learn how to generate, store, and validate passwords securely. Covers entropy, hashing algorithms, salting, and common mistakes in password systems.
Reference
RegEx Cheat Sheet for Developers
A practical regex reference with patterns for emails, URLs, IPs, dates, and more. Covers metacharacters, quantifiers, groups, lookahead, and flags.
Guides
SQL Formatting Best Practices
Learn how to format SQL queries for readability. Covers indentation, capitalization, JOIN alignment, CTE formatting, and team style consistency.
Networking
Subnet Calculator: How to Read CIDR Notation
Learn CIDR notation, subnet masks, network and broadcast addresses, and how to split networks. Includes a visual breakdown and practical examples.
Networking
Understanding DNS Record Types
A complete guide to DNS record types: A, AAAA, MX, CNAME, TXT, NS, SOA, CAA, PTR, and SRV. Learn what each record does and when to use it.
Architecture
UUID vs ULID: Which ID Format to Use?
Compare UUID v4, UUID v7, and ULID for unique identifiers. Learn the trade-offs in sortability, collision probability, database performance, and privacy.
Accessibility
WCAG Contrast Ratio Requirements
Understand WCAG 2.1 contrast ratios for text, UI components, and graphical objects. Learn how to test and fix contrast issues for web accessibility.