Serhii Nezhyhai
Open to interesting work

Building one store and everything around it.

I came to development from e-commerce marketing. For about two years now I've worked almost entirely on Shopify — one store's theme, and the apps and integrations behind it.

Location
Kyiv, Ukraine
Availability
Open to interesting Shopify and AI-commerce work
Last updated
September 2026

Selected work

Full archive

Six projects, one Shopify store.

2024Custom app
Payment & Fiscal Hub dashboard listing issued, excluded and courier-bound orders.

Back-office integration app

A custom Shopify app on Gadget.dev, tying the store to Ukrainian banking, fiscal receipts, a marketplace, a courier and its suppliers.

  • Gadget.dev
  • TypeScript
  • GraphQL Admin API
  • Polaris
  • 10 Admin UI extensions
  • 6 systems wired
  • ~40 models mirrored
2024Performance
Informatica storefront homepage with a Logitech peripherals hero banner.

Informatica storefront

A customised Dawn theme in Liquid for a large Ukrainian electronics catalogue, with a Lighthouse harness that decides what ships.

  • Liquid
  • Online Store 2.0
  • Web Components
  • theme-check
  • 71 / 83 / 88 Lighthouse
  • 6 measured
  • 2 kept
2025AI / agentic
Storefront chat widget answering a laptop-memory question on the live site.

Storefront AI assistant

A shopper-facing chat agent on Claude and MCP — catalogue search, cart building and order status, in Ukrainian and Russian.

  • Claude Haiku 4.5
  • Model Context Protocol
  • Remix
  • Fly.io
  • MCP: Storefront + Customer
  • Ukrainian / Russian
2024–2025Functions
Google Shopping listing and product page showing the automated sale price applied.

Dynamic discounts

A public Shopify app that makes Google's automated discounts actually apply at checkout, as a Shopify Function.

  • Shopify Functions
  • Remix
  • Polaris
  • Prisma
  • Shopify App Store
  • en / uk / ru
2024Integration
Electron + React desktop app fetching products from three suppliers.

Supplier price sync

A desktop app that pulls prices and stock from eight suppliers, re-prices them, and bulk-updates the store and its marketplace feeds.

  • Electron
  • React
  • TypeScript
  • Puppeteer
  • 8 supplier sources
  • Rozetka + Merchant feeds
2023–2025Headless
The retired Hydrogen-based Informatica storefront homepage with a JBL headphones hero banner.

Hydrogen storefront

The store's previous headless build on Hydrogen and Oxygen — retired in 2025 when it moved back to a Liquid theme.

  • Hydrogen
  • Remix
  • Storefront API
  • Oxygen
  • Headless → Liquid
  • Retired 2025
  • Repo left public

About

Focus
Shopify themes, back-office integrations, AI commerce
Everyday stack
Liquid, TypeScript, React, Web Components
Based in
Kyiv, Ukraine
Currently
Shopify developer at Informatica
Shipped
1 public app on the Shopify App Store

It's one store — informatica.com.ua — but the work spreads well past the theme.

I hold a master's degree in IT, but started out in e-marketing, keeping an electronics retailer's website running on WordPress. A 12-month fullstack program and a React internship later, I moved into development properly, and in 2024 I took over the same retailer's Shopify build.

The storefront is a customised Dawn theme in Liquid, with the interactive parts written as plain Web Components rather than a framework. Around it sits a custom Shopify app on Gadget.dev for banking, fiscal receipts and the Rozetka marketplace; an Electron price-sync tool; an AI chat assistant on Claude and the Model Context Protocol; and a public Shopify app for Google's automated discounts.

40+
Shopify models mirrored
8
Supplier sources synced
6
Market integrations wired

Tools and practice

What I reach for.

LiquidOnline Store 2.0Web ComponentsAjax & Section RenderingMetafields & metaobjectsShopify Functionstheme-checkGraphQL Admin APIGadget.devPolarisLiquidOnline Store 2.0Web ComponentsAjax & Section RenderingMetafields & metaobjectsShopify Functionstheme-checkGraphQL Admin APIGadget.devPolaris
TypeScriptReactRemixApp BridgeAdmin UI extensionsModel Context ProtocolEmbeddings & retrievalElectronCloudflare WorkersCore Web VitalsTypeScriptReactRemixApp BridgeAdmin UI extensionsModel Context ProtocolEmbeddings & retrievalElectronCloudflare WorkersCore Web Vitals

Let's talk about the work.

nezhihai@gmail.com