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Developer Guides

100 articles

In-depth tutorials and best practices for the technologies behind your favorite developer tools — hashing and password storage, image and PDF internals, HTTP and DNS, regular expressions, and the browser APIs the tools are built on.

Written and edited by Necmeddin Cunedioglu. Every article is original to this site, carries a publish date, and is corrected in place when something changes — see the editorial policy.

Comprehensive Guides

📖 Pillar Guide

Core Web Vitals in 2026: The Complete INP, LCP, and CLS Optimization Playbook

A practical guide to Core Web Vitals now that INP replaced FID: what LCP, INP, and CLS measure, the thresholds that matter, and how to pass each one.

📖 Pillar Guide

Generative Engine Optimization (GEO): How to Get Cited by AI Search in 2026

A practical guide to Generative Engine Optimization: how ChatGPT, Google AI Overviews, and Perplexity pick and cite sources — and how to earn the citation.

📖 Pillar Guide

Prompt Engineering for Developers: Patterns That Actually Work in 2026

A no-hype guide to prompt engineering for real LLM apps: roles, few-shot, chain-of-thought, structured output, RAG, and evaluation patterns that work.

📖 Pillar Guide

PDF vs DOCX: Structural Document Formats Comparison

PDF vs DOCX architecture: fixed-layout coordinate systems vs reflowable XML text nodes, plus font embedding — and what each format is really for.

📖 Pillar Guide

Developer Generators: The Tools That Save You Hours Every Week

The generators every developer needs — UUIDs, passwords, QR codes, favicons, meta tags, robots.txt, and .gitignore — and when, why, and how to use each.

📖 Pillar Guide

The Complete Guide to Browser-Based Image Editing

Image processing in the browser: Canvas drawImage(), resampling algorithms, format conversion, EXIF extraction, local PDF generation — plus WebAssembly, Web Workers, why local beats the cloud on latency, and how to verify a tool is really client-side.

📖 Pillar Guide

Time & Date in Programming: The Complete Developer Guide

A developer's guide to handling time: the Unix epoch and Year 2038, IANA timezones and DST, JavaScript Date traps, ISO 8601, cron scheduling, TIMESTAMPTZ vs DATETIME, forcing TZ=UTC, and a pre-deploy checklist.

📖 Pillar Guide

HTTP Status Codes: The Complete Guide for Developers

A complete guide to HTTP status codes: 401 vs 403, the SEO impact of 301 vs 302, 409 for optimistic locking, and how to monitor 5xx errors properly.

📖 Pillar Guide

CSS Color Systems: A Complete Guide for Developers

Master CSS color formats — HEX, RGB, HSL, and Color Level 4: when to use each, how to build consistent palettes, and what perceptual uniformity means.

📖 Pillar Guide

Web Security: Encoding and Hashing Guide

Encoding vs hashing vs encryption: when to use Base64, SHA-256, bcrypt, AES-256-GCM and HTML entity encoding — with decision trees, the Kubernetes Secrets and JWT misconceptions, and working replacement code.

📖 Pillar Guide

Regular Expressions: The Complete Guide

The complete regex reference: syntax, quantifiers, anchors, groups and lookarounds, NFA backtracking and ReDoS, per-language gotchas in JS/Python/Java, plus tested patterns for email, URLs, IPs and dates.

📖 Pillar Guide

JSON: The Complete Developer Guide

Everything about JSON: syntax and the six types, reviver/replacer, V8 parsing internals, BigInt precision loss, streaming large payloads, JSON Schema validation with Ajv, JSONPath querying, and REST API practice.

AI Tools

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Network & API

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Web Security

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Security & Cryptography

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Image Processing

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Encoding

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Text Processing

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Web Performance

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Time & Date

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CSS & Design

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Color & CSS

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Developer Tools

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Web Development

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Format & Document

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Generators

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Data Formats

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Format Conversion

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Format & Convert

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Productivity

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