# Guides Reusable technical guides for the tools and topics on ilham.dev: debugging, configuration, data formats, security, networking, documents, and everyday developer workflows. 30 guides. ## [API Testing](https://ilham.dev/guides/api-testing/) - Markdown: https://ilham.dev/guides/api-testing/index.md - Tags: web - Description: Using OpenAPI files, mock responses, webhooks, gRPC testers, and request tools without copying blindly. ## [Browser Debugging Utilities](https://ilham.dev/guides/browser-debugging/) - Markdown: https://ilham.dev/guides/browser-debugging/index.md - Tags: web - Description: Device info, network info, key codes, microphones, cameras, JavaScript playgrounds, and browser-side testing. ## [Browser File Tools](https://ilham.dev/guides/browser-file-tools/) - Markdown: https://ilham.dev/guides/browser-file-tools/index.md - Tags: privacy - Description: Small browser-side file tasks such as zip creation and Base64 conversion, with privacy boundaries. ## [Browser Games and Practice Tools](https://ilham.dev/guides/browser-games-and-practice-tools/) - Markdown: https://ilham.dev/guides/browser-games-and-practice-tools/index.md - Tags: web - Description: Small browser games and practice utilities that live under tools without becoming blog posts. ## [Calculators and Unit Conversion](https://ilham.dev/guides/calculators-and-unit-conversion/) - Markdown: https://ilham.dev/guides/calculators-and-unit-conversion/index.md - Tags: data - Description: Percentages, discounts, loans, interest, unit prices, currency, temperature, fuel economy, number bases, and roman numerals. ## [Dates, Timestamps, and Time Zones](https://ilham.dev/guides/dates-times-and-time-zones/) - Markdown: https://ilham.dev/guides/dates-times-and-time-zones/index.md - Tags: data - Description: Dates, durations, timestamps, time zones, age calculations, stopwatches, and ETA estimates. ## [Debugging CORS Without Guessing](https://ilham.dev/guides/debugging-cors/) - Markdown: https://ilham.dev/guides/debugging-cors/index.md - Tags: web - Description: A practical way to reason about CORS errors, preflight requests, credentials, and browser behavior. ## [Docker Basics](https://ilham.dev/guides/docker-basics/) - Markdown: https://ilham.dev/guides/docker-basics/index.md - Tags: devops - Description: Dockerfiles, Compose conversion, logs, and the small container details that matter during development and ops. ## [Email Debugging](https://ilham.dev/guides/email-debugging/) - Markdown: https://ilham.dev/guides/email-debugging/index.md - Tags: security - Description: Email headers, normalized addresses, suspicious messages, and the limits of what email metadata can prove. ## [Filtering Docker Logs Effectively](https://ilham.dev/guides/docker-logs/) - Markdown: https://ilham.dev/guides/docker-logs/index.md - Tags: devops - Description: How to filter Docker container logs without losing useful context, timestamps, and failure clues. ## [HTTP and API Debugging](https://ilham.dev/guides/http-api-debugging/) - Markdown: https://ilham.dev/guides/http-api-debugging/index.md - Tags: web - Description: Requests, headers, auth headers, status codes, curl, MIME types, and small checks before blaming the API. ## [IDs and Test Data](https://ilham.dev/guides/ids-and-test-data/) - Markdown: https://ilham.dev/guides/ids-and-test-data/index.md - Tags: data - Description: UUIDs, ULIDs, generated MAC addresses, and safe fake identifiers for tests and examples. ## [Indonesian Data Formats](https://ilham.dev/guides/indonesian-data-formats/) - Markdown: https://ilham.dev/guides/indonesian-data-formats/index.md - Tags: data - Description: NIK, phone numbers, spelled numbers, local salary estimates, maps links, and Indonesian text checks. ## [Linux Command Line Tasks Without Surprises](https://ilham.dev/guides/linux-command-line/) - Markdown: https://ilham.dev/guides/linux-command-line/index.md - Tags: linux - Description: Practical notes for find, grep, sed, xargs, chmod, cron, and other commands that are easy to misuse. ## [Network Debugging Notes](https://ilham.dev/guides/network-debugging/) - Markdown: https://ilham.dev/guides/network-debugging/index.md - Tags: networking - Description: DNS, WHOIS, IP addresses, ports, subnets, MAC addresses, Wi-Fi QR codes, and SSH tunnels. ## [Nginx Reverse Proxy Configuration](https://ilham.dev/guides/nginx-reverse-proxy/) - Markdown: https://ilham.dev/guides/nginx-reverse-proxy/index.md - Tags: devops - Description: Common nginx reverse proxy configuration patterns, headers, upstreams, TLS, and debugging checks. ## [Practical Image Tools](https://ilham.dev/guides/practical-image-tools/) - Markdown: https://ilham.dev/guides/practical-image-tools/index.md - Tags: privacy - Description: Image compression, format conversion, metadata removal, redaction, QR codes, placeholders, stickers, and watermarks. ## [Reading Logs Before Searching Randomly](https://ilham.dev/guides/reading-logs/) - Markdown: https://ilham.dev/guides/reading-logs/index.md - Tags: devops - Description: Parsing logs, preserving context, checking timestamps, and narrowing down failures before random searching. ## [Security and Cryptography Basics for Developers](https://ilham.dev/guides/security-cryptography-basics/) - Markdown: https://ilham.dev/guides/security-cryptography-basics/index.md - Tags: security - Description: Hashing, encoding, signatures, keys, passwords, tokens, and crypto terms developers often meet while debugging systems. ## [SQL Formatting and Test Data](https://ilham.dev/guides/sql-formatting-and-test-data/) - Markdown: https://ilham.dev/guides/sql-formatting-and-test-data/index.md - Tags: database - Description: Formatting SQL, generating inserts, and preparing small data sets for review or testing. ## [Testing and Debugging WebSockets](https://ilham.dev/guides/websocket-debugging/) - Markdown: https://ilham.dev/guides/websocket-debugging/index.md - Tags: networking - Description: How to test browser WebSocket connections, inspect frames, and think about proxy-related failures. ## [Testing Regex Before Shipping It](https://ilham.dev/guides/regex-testing/) - Markdown: https://ilham.dev/guides/regex-testing/index.md - Tags: automation - Description: How to test matching and replacement patterns before using regex in real code or shell commands. ## [Text Formatting and Cleanup](https://ilham.dev/guides/text-formatting-and-cleanup/) - Markdown: https://ilham.dev/guides/text-formatting-and-cleanup/index.md - Tags: automation - Description: Case conversion, line formatting, text statistics, Unicode, binary views, emoji, NATO spelling, and message formatting. ## [Understanding and Debugging JWTs](https://ilham.dev/guides/jwt-debugging/) - Markdown: https://ilham.dev/guides/jwt-debugging/index.md - Tags: security - Description: How to read JWT headers and claims, check expiry, and understand what signature verification does and does not prove. ## [Web Metadata](https://ilham.dev/guides/web-metadata/) - Markdown: https://ilham.dev/guides/web-metadata/index.md - Tags: web - Description: Meta tags, Open Graph previews, UTM links, and the page data used by browsers, crawlers, and social apps. ## [Working With Configuration Files](https://ilham.dev/guides/configuration-files/) - Markdown: https://ilham.dev/guides/configuration-files/index.md - Tags: devops - Description: Reading, sorting, and editing configuration files without moving comments or changing meaning. ## [Working With PDFs](https://ilham.dev/guides/working-with-pdfs/) - Markdown: https://ilham.dev/guides/working-with-pdfs/index.md - Tags: privacy - Description: PDF metadata, page extraction, merging, signatures, and browser-side document handling. ## [Working With Structured Data](https://ilham.dev/guides/working-with-structured-data/) - Markdown: https://ilham.dev/guides/working-with-structured-data/index.md - Tags: data - Description: JSON, YAML, TOML, XML, CSV, JSONPath, schemas, diffs, viewers, and format conversion caveats. ## [Working With URLs](https://ilham.dev/guides/working-with-urls/) - Markdown: https://ilham.dev/guides/working-with-urls/index.md - Tags: web - Description: Parsing URLs, encoding query strings, reading slugs, and checking redirected or wrapped links. ## [Writing and Publishing Text for the Web](https://ilham.dev/guides/writing-for-the-web/) - Markdown: https://ilham.dev/guides/writing-for-the-web/index.md - Tags: web - Description: Markdown previews, HTML entities, slugs, URL encoding, and simple publishing tasks.