ENDEUARU

Mönchengladbach, Germany · open to talk

IvanKupach

Lead Fullstack Engineer

I build real-time web platforms. 8+ years of it. Right now I lead engineering on a sports data platform that streams thousands of live fixtures over WebSockets to web and mobile, and I own it from the Postgres schema up to the Lighthouse score.

Download CV PDF
ivankupach@gmail.com+49 162 2021427github/ivankupachlinkedin/in/ivankupach

The numbers

0+

Years shipping

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Hot-path reads

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Lighthouse

0

Locales, SEO'd

0

Languages spoken

Where I've worked

Lead Fullstack Engineer · Notbet, London

  • Built a real-time sports data platform from scratch: web app, public API, and the services behind both web and mobile through a BFF layer.
  • Next.js 14 frontend, Node.js services for live scores, stats and fixtures, on PostgreSQL (raw SQL, PgBouncer) and Redis for snapshots, pub/sub and WebSocket fan-out.
  • Designed a high-throughput transaction engine: placement, matching, proceed/recalculate/resolve, soft-delete-safe upserts, ML-enriched metadata.
  • Latency-critical routes read pre-materialized Redis snapshots, so the request path stays under 100ms.
  • Led the mobile team on data and contract decisions, ran reviews across web and mobile, set the standards, drove the migrations.
  • Owned SEO end-to-end: SSR/metadata, structured data, sitemap and hreflang across 8 locales. LCP under 1.5s.
  • Shipped product on top: ML insights, weekly rewards, Telegram Mini App, Stripe, Auth.js flows.
  • CI/CD on Docker Swarm via Dokploy. My deploys, my rollbacks, my 3am incidents (Grafana, Sentry, PostHog).

Senior Front-End Engineer · Kyros AI, Silicon Valley

  • Led technical design on a React/TypeScript product, whiteboard to production, across cross-functional teams.
  • Turned complicated AI workflows into UIs people could actually move through fast.
  • Ran a phased modernization of a big legacy codebase (hooks, TypeScript, modern data-fetching) without freezing feature delivery.
  • Set the unit and integration testing standards for UI, so regressions got caught before release instead of after.
  • Mentored mid-level engineers through review, pair debugging and architecture walkthroughs. Helped with hiring.

Fullstack Developer · Solution Plus Limited, London

  • Delivered production apps end-to-end on Next.js, Vue/Nuxt and Node.js: onboarding flows, dashboards, transaction UX.
  • Designed the APIs and data models under them, trading latency against reliability and cost.
  • Owned the whole SDLC per client: requirements, architecture, build, test, deploy, support.
  • Security-first by default: credential handling, input validation, CSRF/XSS hardening around sensitive data.

Frontend Developer · QFinds, London

  • Architected the frontend for a customer-facing product and built the component library that cut new-feature time.
  • Worked with PMs and solution architects to sanity-check feasibility and scope the messy roadmap items.
  • Tuned the client: bundle splitting, lazy loading, caching. Low-end devices stopped feeling slow.

Fullstack Developer · Freelance, Remote

  • Built a student forum for Sumy University: architecture, auth, moderation, discussions. Solo, for the whole university community.
  • Every layer was mine: UI/UX, API design, DB schema, deployment, maintenance.

What I work with

Languages

  • JavaScript
  • TypeScript
  • Python
  • SQL

Frontend

  • React
  • Next.js 14 App Router
  • Vue
  • Nuxt
  • SCSS / CSS Modules
  • TanStack Query
  • Zustand
  • SSR
  • SEO

Backend

  • Node.js
  • Python
  • REST
  • WebSockets
  • BFF patterns
  • Auth.js

Data

  • PostgreSQL
  • MongoDB
  • Redis
  • pub/sub
  • read models

Infrastructure

  • Docker
  • Docker Swarm
  • Kubernetes
  • AWS
  • Dokploy
  • CI/CD
  • Grafana
  • Sentry
  • PostHog

Practices

  • System design
  • Microservices
  • Real-time systems
  • Monorepos
  • Code review
  • Mentoring
  • Jest
  • Agentic dev
  • Claude Code
  • MCP servers

Languages & school

UkrainianNATIVE

RussianNATIVE

EnglishB2 / C1

GermanB2

BSc Computer Science

Sumy State University · —

Let's build something

Got a platform that has to stay up and stay fast? Tell me about it. I read everything that lands here.

Or reach me directly

ivankupach@gmail.com+49 162 2021427TelegramLinkedIn