Alexandr Sopilnik
Developer: JavaScript, TypeScript, Rust, React, Next.js, Node.js, Tauri
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🛡️ Geverifieerd sinds September 2026
Over
If your website or app is broken, slow, or was built with AI and nobody can maintain it now, I can fix it. If you are starting from scratch, I can build it properly the first time.
I have been a web developer since 2016 for e-commerce and small-business clients: HTML, CSS and JavaScript first, then TypeScript, React and Next.js on the front end with Node.js behind them. I build and fix WordPress and WooCommerce sites too, and since 2024 I have been writing Rust most working days. The largest project so far was the backend of an educational platform: microservices on axum, Kafka between services, PostgreSQL and Redis, gRPC inside and REST for the front end.
What I take on:
- Apps generated with AI tools that work for the founder but are not ready for real users yet: flaky logins, payments that fail, missing access rules, code nobody wants to touch
- Bug fixes and cleanup on existing WordPress, WooCommerce, React, Next.js and Node.js projects
- New sites and web apps, with the interface designed and hand-coded by me in HTML, CSS/SCSS and React
- Desktop apps with Tauri and mobile apps with React Native
- Backends and APIs in Node.js/TypeScript (Express, NestJS) or Rust; payment and third-party integrations; PostgreSQL with row-level security for paid plans
- Performance: slow pages, slow endpoints, slow queries
A few results, all under NDA:
- Rewrote a legacy PHP backend in Node.js/TypeScript with the public API kept compatible, so the front end shipped unchanged. Median response time on the main endpoints dropped by roughly 3x.
- Moved a jQuery front end to React page by page while the product stayed live.
- Worked on paid access enforced inside PostgreSQL: row-level security policies and a separate role for each subscription tier.
How I work: async and in writing. I write the scope down before starting and prefer a fixed price for anything well defined, hourly while the shape is not clear yet. You get a short written update at the end of each working day, and no calls are needed. I use AI coding tools every day as an assistant, and I read and test everything they produce. Working hours are 10:00-20:00 Almaty time (UTC+5), which covers most of the European business day and the start of the business day on the US East Coast.
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Portfolio
Formline: Next.js store with Stripe
A storefront you can click through: 16 posters in 4 collections, filters and search that stay in the URL, a cart, light and dark themes, and a checkout that ends in a demo order or a real Stripe Checkout session in test mode. I built it as a Next.js static export in TypeScript with Tailwind CSS. Poster images are generated from SVG templates and rendered to PNG at build time. Card payments go through a Cloudflare Worker that re-prices the cart on the server and verifies Stripe's webhook signature. Vitest and Playwright tests run in GitHub Actions on every push; pushes to main deploy the site.
reqwest-rotate: open-source crate
A small reqwest wrapper for scrapers and API clients that need proxy rotation, per-host rate limiting and retry with backoff, without pulling in a middleware framework. Published on crates.io with docs, CI and about two hundred tests.
Bilingual personal site in Next.js
A one-page personal site in English and Russian, with a services section and links to my demo projects. I designed and built it with Next.js, React and TypeScript as a static export, styled with plain CSS Modules and no UI framework. It has light and dark themes, and a social preview image for each language is generated at build time. GitHub Actions builds and deploys it to Bunny CDN, which adds security headers and redirects www and plain HTTP to the main HTTPS address.
Rust microservices, EdTech backend
I built the backend: Rust services on axum, Kafka for events between services, PostgreSQL and Redis, gRPC inside, REST for the React front end. Docker, CI/CD. Client under NDA.
PHP backend rewritten in Node.js/TS
Rewrote the backend of a client's web platform from legacy PHP to Node.js/TypeScript and kept the public API compatible, so the front end shipped unchanged. Median response time on the main endpoints dropped by roughly 3x. Deployment moved to Docker with CI/CD. Client under NDA.
jQuery to React migration, live app
Moved a jQuery front end to React page by page while the product stayed in production. jQuery is gone, the UI is component-based, and new features are built on the React side. Client under NDA.
React + Node.js + PostgreSQL app
Built the front end, backend and database for a client: React, TypeScript on Node.js, PostgreSQL, shipped as one deployable service with CI/CD. Client under NDA.
Rust CLI tools and scrapers
Command-line utilities, scrapers and parsers in Rust that collect narrow-domain data for clients (async, reqwest, scraper, serde). Proxy rotation and rate-limit handling when a site requires it; targets range from static HTML to JS-rendered pages. Sources and datasets are under NDA.
Gladiator-school sim in Rust/Bevy
Management sim with pre-simulated combat and an event log, a d20 hit-location system, utility AI and an economy layer. Built on Bevy ECS, with an automated test suite.
