Sgdev
Open to collaborations

I build fast, secure software for the modern web.

Right now: FastAPI backends

I'm Shubhomoy (Sgdev), a full-stack and AI developer. I work with Python, FastAPI and edge hosting to ship tools that are quick, private and easy to use.

View projects Read Blog & Papers Open Clock ⚙️ Explore the 404 page 🌊
Shubhomoy (Sgdev)

Learning by building.

Every project here started as an experiment and grew into something people can use, from a captcha engine to an AI chat app and RF network case studies.

I care about performance, clean code and keeping things simple, and I'm always open to technical discussions and API integrations.

  • BackendPython, FastAPI and Flask on Render and Vercel serverless.
  • FrontendSemantic HTML, modern CSS and vanilla JavaScript.
  • Security & ResearchHMAC and SHA-256 hashing, network telemetry and RF metrics analysis.
  • Deployment & DNSVercel, Hurricane Electric DNS, GitHub Actions and hybrid mail routing.

Three colours, three languages.

Every page here is built with just HTML, CSS and JavaScript. No frameworks. The three accent colours stand for these three languages. Tap a button to repaint the whole site.

HTML

Red · Structure

HTML is the skeleton of every page: headings, links, buttons and forms. Tim Berners-Lee created it in the early 1990s.

Here it builds the nav, project cards, calculator keys and game boards.

CSS

Blue · Style

CSS controls how everything looks: colours, layout, animation and responsive design. It was proposed in 1994 by Håkon Wium Lie.

Here it draws the dark theme, the moving strip, the hover effects and the phone layout.

JavaScript

Yellow · Behaviour

JavaScript makes pages interactive. Brendan Eich wrote the first version at Netscape in 1995 in about ten days.

Here it runs the fidget spinner, calculator, SHA-256 tool, password generator and all five games.

Selected projects & research

Tools and technical papers I designed, built and run myself.

S-Captcha Maintenance

A captcha system that needs no database. It layers invisible checks, text challenges and an image honeypot, and rate-limits with hashed IP addresses. It is under maintenance, so it may be briefly unavailable.

PythonFastAPISHA-256
Open project
Hi, how can I help?Explain FastAPI routes

SAI In development

A chat app for quick answers, code help and developer support. Features are still being added.

AIWeb app
Open project
5GNSA

Research Blog Active

Independent write-ups on Windows MAS HWID, C2R Office, 5G NSA Network Telemetry.

RF TelemetrySystems Internals
Visit Blog

Clock Live

A live clock tool you can open in the browser, built with plain HTML, CSS and JavaScript.

HTMLCSSJavaScript
Open Clock

More on GitHub Live

Browse the full codebase, experiments and open-source work. These numbers load straight from GitHub when you scroll here.

–repos –followers –following

    github.com/sgdev-official

    Tools & toys

    Small utilities that run fully in your browser. Nothing you type here is sent anywhere.

    0

    History

    1. Your calculations show up here.

    Arcade

    Five quick games written in plain JavaScript. Your scores are saved in your browser only.

    Your turn (X)

    0You 0Draw 0AI

    Let's build something together.

    Email is the fastest way to reach me. I'm happy to talk about collaborations, technical research, and software integrations.

    info@sgdev.qd.je info@sgdev.is-cool.dev GitHub Research Blog Clock