# Zyekh Abdul Qadir Jailani (zyekh.com)

> Official website, technical security research blog, and client-side web utility tools by Zyekh Abdul Qadir Jailani (Full Stack Developer & Security Researcher).

## About
Zyekh Abdul Qadir Jailani is a Full Stack Developer & Security Researcher specializing in enterprise backend architecture, Linux kernel security hardening, eBPF security monitoring, and Android modding.

- Website: https://zyekh.com/
- GitHub: https://github.com/zyekhabdul
- Email: aqz220309@gmail.com

## Web Utility Tools (Client-Side & Privacy-First)
- [Kalkulator Zakat Online](https://zyekh.com/tools/zakat.html): Calculate Zakat Maal and Zakat Profesi (Income) based on 85g gold nisab and 2.5% rate.
- [Kalkulator PPh 21 TER](https://zyekh.com/tools/pph21.html): Calculate PPh 21 employee income tax with TER (Tarif Efektif Rata-Rata) Category A, B, C & PTKP.
- [Simulasi KPR Online](https://zyekh.com/tools/kpr.html): Calculate KPR home mortgage monthly payments, fixed & floating interest rates, and loan table.
- [Kalkulator THR Pro-Rata](https://zyekh.com/tools/thr.html): Calculate Indonesian Tunjangan Hari Raya (THR) pro-rata based on tenure and Permenaker regulations.
- [Split Bill Online](https://zyekh.com/tools/split-bill.html): Proportional bill splitter with tax and service charge calculations.
- [Secure Password Generator](https://zyekh.com/tools/password.html): Cryptographically secure random password generator using Crypto Web API.
- [QR Code Generator](https://zyekh.com/tools/qr.html): Free high-definition QR code generator.
- [Diff Checker](https://zyekh.com/tools/diff-checker.html): Side-by-side text and code difference comparison tool.
- [Pomodoro Timer](https://zyekh.com/tools/pomodoro.html): Focus timer for productivity and study.
- [Text Case Converter](https://zyekh.com/tools/case-converter.html): Convert text between UPPERCASE, lowercase, camelCase, snake_case, and kebab-case.
- [Color Palette & Converter](https://zyekh.com/tools/color.html): Convert HEX, RGB, HSL color formats with palette generator.
- [Unit & Currency Converter](https://zyekh.com/tools/converter.html): Client-side unit and measurement converter.
- [Countdown Timer](https://zyekh.com/tools/countdown.html): Customizable event countdown timer with alert sounds.
- [Word & Character Counter](https://zyekh.com/tools/counter.html): Real-time word, character, sentence, paragraph, and reading time counter.
- [Random Dice & Number Picker](https://zyekh.com/tools/dice.html): Cryptographically fair random number and dice roller.
- [Lorem Ipsum Generator](https://zyekh.com/tools/lorem.html): Customizable placeholder text generator for developers and designers.
- [Markdown Live Editor](https://zyekh.com/tools/markdown.html): Live preview Markdown editor with GFM support and HTML export.
- [Random Item Picker](https://zyekh.com/tools/random-picker.html): Decision-making tool to pick items randomly from custom lists.
- [Text to Speech (TTS)](https://zyekh.com/tools/tts.html): Client-side voice synthesizer using SpeechSynthesis Web API.
- [Web Tools Hub](https://zyekh.com/tools/): Access all 19+ client-side web utilities.

## Articles & Research
- [Comprehensive Linux VPS Hardening Blueprint](https://zyekh.com/blog/linux-vps-hardening-guide-2026.html): Step-by-step Debian/Ubuntu server security guide.
- [Understanding eBPF Security Monitoring](https://zyekh.com/blog/understanding-linux-ebpf-security-monitoring.html): Kernel event monitoring and real-time observability.
- [Strict Content Security Policy (CSP) & Headers](https://zyekh.com/blog/securing-web-applications-with-strict-content-security-policy.html): Eliminating XSS and clickjacking vulnerabilities.
- [Minimalist Static Hosting Architecture](https://zyekh.com/blog/minimalist-server-architecture-pure-css-and-static-hosting.html): Attack surface reduction via static edge hosting.
- [Articles Hub](https://zyekh.com/blog/): Read all technical research articles.