RootFox

Stack

About me

Organization

Fundamentals

APIs

REST · OpenAPI · WebSockets

Auth

OAuth · JWT

Current

Languages & frameworks

TypeScript · JavaScript · Node.js · React · Svelte · SvelteKit · Go · Next.js · Nuxt

Frontend tooling

Zustand · Vite · Storybook

Backend

GraphQL · NestJS · Express / Koa · BullMQ · RabbitMQ · Stripe

Data

PostgreSQL · MongoDB · Redis

Infrastructure

Docker · GCP · AWS · Cloudflare · Kubernetes · GitHub Actions · GitLab CI

Testing

Vitest · React Testing Library · Playwright · BrowserStack

Observability

Sentry · Grafana · Prometheus · k6 · Lighthouse

AI & agents

Hermes · OhMyPi · LightPanda · GoModel · MCP · RAG · Design Gate / TDD

Tail MCP · Jev MCP · Foxling

Other

Bots · Hobby Games · Pixi.js · Flutter

Earlier

Servers

Linux administration · Debian · FreeBSD · nginx · OpenResty

CMS & E-commerce

PHP · Drupal · WordPress · Shopify

Payments

Robokassa · YooMoney · WebMoney

Frontend & testing

Redux · Cypress

AI tooling

Cursor · Claude Code · OpenCode · OpenRouter · Pi · Superpowers

Other

Steam API

Alex Vopilovskiy

FullStack Engineer • Entrepreneur

I build products end to end, from the first idea and architecture to production and everything in between. I like owning the whole system: backend, frontend, infrastructure, integrations, and the edge cases that make software actually work.

I prefer simple systems, small changes, explicit boundaries, and short feedback loops. I verify assumptions against reality, keep failures reversible, and treat scope control as an engineering skill. There is rarely a single best practice, only trade-offs that should be understood and made explicit.

My Principles

This is the way

Companies I worked for

Legal name: Aleksandr Vopilovskii pr RootFox
Country: Serbia
Registered address: Jurija Gagarina 231, local 329
11197 Beograd (Novi Beograd), Serbia
Registration no.: 68471168
Registration Date: 10 March 2026
Registering authority: Serbian Business Registers Agency
Tax ID (PIB): 115575108
D-U-N-S: 369907635
Email: sef@rootfox.cc
Bank: Alta Bank

Legal name: Individual Entrepreneur Aleksandr Vopilovskii
Country: Georgia
Registered address: Tbilisi, Krtsanisi district, Fonichala settlement 3, building 5
Registration no.: 304647568
Registration Date: 25 August 2022
Registering authority: LEPL National Agency of Public Registry
Email: georgia@rootfox.cc
Bank: Bank of Georgia

Apps

Nonogram

Logic picross puzzles

Mines

Classic minesweeper puzzle

Helicopter

One-touch arcade flyer

Sudoku

Classic number puzzle

MadNews

Absurd headline generator

Rock-Paper-Scissors

Online multiplayer rock-paper-scissors

Crack the Code

Logic code puzzle

Chess

Play against Stockfish AI

Projects

Foxling

Personal assistant in Telegram: reminders, memory, and calendar in your own words. Website

Open

Frontend Auditor

Lighthouse and Core Web Vitals scores plus the static checklist: meta, favicons, links, images, and HTML validity.

Visit

CV Analyzer

ATS-friendly CV review: scores across six recruiter platforms, an extracted-profile check, and prioritized fixes.

Visit

Ping-Pong

Service that helps friends see who made the last move: invited for a walk, wrote first. A simple way to maintain balance in relationships.

Visit

InstaFox

My personal photography portfolio with Instagram-like gallery.

Visit

FoxFamily

Interactive family tree visualization.

Visit

Notepad

Personal notes app with a vintage macOS feel. Go, MongoDB, and Svelte.

Visit

Chat

Global realtime chat. No signup, no database - just open and talk.

Visit

VChat

Mesh video chat. No signup - just open a room and talk.

Visit

Planning Poker

Scrum planning poker: reveal every vote on a board, plus the numeric average.

Visit

Foxling

Personal assistant in Telegram: reminders, memory, and calendar in your own words. Website

Open

Tail MCP

MCP server plus a browser extension that lets AI assistants drive your own logged-in browser. Local-only — no cloud backend.

GitHub

Jev MCP

MCP server that gives coding agents a judge: twelve typed verdict tools returning the chosen option, the full distribution, and an action.

GitHub

Copter

Remake of the classic Flash game.

Play

Fox Story

Work in progress. Walk as a fox through a quiet forest - with a live day-night sky cycle.

Play

Nonogram

Japanese crossword puzzle game.

Play

Mines

Classic minesweeper game.

Play

Sudoku

Classic number puzzle game.

Play

Mahjong

Match open tiles through the buffer. Clear the board to win.

Play

Rock-Paper-Scissors

Online multiplayer rock-paper-scissors game.

Play

Chess

Play against Stockfish. Four difficulty levels.

Play

Crack the code

Mastermind-style code breaking game.

Play

Piano Hero

Guitar Hero style piano game.

Play

Handbook

My life, my rules.

View

AllCart team welcome

Old welcome page for new AllCart team members.

View

911 Carrera · G-Series

Porsche 911 Carrera 3.2 Coupé M491 G50

View

Spitfire

Supermarine Spitfire · Merlin & Griffon · RAF

View

Traphole Music Player

Custom music player for my old band's tracks.

Listen

F1 Team Names

Every official team name on the 2026 grid - with era photos.

View

Coub

Collection of my favorite coubs.

Visit

Pentafoxianism

A satirical religion website with commandments and pantheon.

Explore

Steam Inventory Info

Tool to analyze Steam inventory items and their values.

Open

Band "coming soon"

Nostalgic "coming soon" page for my old music band.

View

Bad Advice Oracle

Ask a question. Helpful answers not included.

Consult

MadNews

Random crazy news headline generator.

Visit

MadNews Bot

Mad news generator in Telegram - plus horoscopes, rates, and bad advice. Source

Open

8th March

Interactive greeting card for International Women's Day.

View

Johnny Castaway Screensaver

Funny old screensaver about Johnny.

Explore

Scholastic Pie Chart

Interactive pie chart with unexpected twist.

View

Look Generator

Random outfit combination generator.

Generate

Certificate

Generate funny certificates for your friends.

Create

Fast Casino

The fastest casino game you'll ever play.

Play

Black Hole

404 page

Open

Matrix

The Matrix screensaver

Open

Night Toggle

Pure HTML+CSS day/night toggle animation.

View

Cube

3D CSS cube experiment.

View

Cube 2

Advanced 3D CSS cube with more effects.

View

Password Generator

Fast, secure, crypto-grade random passwords in the browser.

Visit

Image Convert

Drop an image in the browser. Get lossless WebP, max-quality JPEG, and PNG when alpha is present.

Visit

Vectorizer

Trace PNG, JPG, or WebP into a clean SVG right in the browser. Nothing uploads.

Visit

Frontend Auditor

Lighthouse, Core Web Vitals, meta, favicons, and HTML validity in one audit.

Visit

OG Preview

How a link preview looks on X, Facebook, LinkedIn, WhatsApp, and Discord - straight from its OG tags.

Visit

HTML Validator

Check HTML by URL, file, or pasted source - powered by the W3C Nu checker.

Visit

Favicon Checker

Check what favicons a site declares, what loads, and what is missing.

Visit

CV Analyzer

ATS review of your CV: platform scores, profile extraction, and prioritized fixes.

Visit

IP Whois

Look up geolocation and network details for any IP address.

Visit

DIG Whois

DNS records and WHOIS data for any domain.

Visit

Darkroom

RAW photo editor in the browser. Sony ARW and Canon CR2/CR3, no upload — decoding, tone and color run locally.

Visit

Epoch Converter

Convert Unix timestamps to dates and back, with a live world clock: UTC, CET, EST, PST, Moscow, Vladivostok and more.

Visit