55+ Developer Tools
A working command center for engineers — JSON formatter, regex builder, JWT debugger, API client and more.
About
Phạm Bảo Hưng
Leoodz · Vietnamese developer & toolmaker
This site is a small system. A developer hub with 55+ offline utilities, a RAG-powered chatbot template, malware-research field notes, and the dev work that ships in between. Everything here is built the same way: started, broken, rebuilt, shipped.
Story
Xin chào.
I'm Phạm Bảo Hưng, known online as Leoodz — a developer who builds tools for other developers. The hub you'll find under /tools started as a private command center and slowly grew into a public one.
Alongside the Hub I ship research on real-world malware samples, run a small RAG template built on Ragie and the Vercel AI SDK, and occasionally help teams localize products for Vietnamese users. Whether I'm formatting JSON, building regex patterns or testing APIs, the goal is the same: make the small moments disappear so the interesting work shows up.
What I've built
04 factsVietnamese Heritage
Localization, lunar calendar and Vietnamese-first ergonomics built into every surface.
Privacy-First
Every utility runs locally. No telemetry. No tracking. Your data never leaves the machine.
Performance Focused
Optimized for speed and the daily workflows of professional engineers.
Technical skills
Working withJavaScript/TypeScriptReact/Next.jsNode.jsPythonVietnamese LocalizationUI/UX DesignDeveloper ToolsWeb Development