~/potatohd.orgRU

// product · backend · highload

Mark Kornachuk

Senior Product Engineer

I design high-load systems and build products end to end — Go backends, Next.js web, native mobile, infrastructure and deployment. Currently building the customer segmentation platform at T-Bank, and co-founder and CTO of Arkot outside of it.

◇ Based in Armenia · UTC+4 · working remotely

Message me on Telegram ↗
EmailGitHub ↗LinkedIn ↗

/stack

Stack

Languages
Go · TypeScript · Python
Backend
Microservices · gRPC · REST · Clean Architecture
Events & streaming
Kafka · Apache Flink · Temporal · Redis pub/sub
Data
PostgreSQL · ClickHouse · ScyllaDB · Redis · Qdrant
Infrastructure
Kubernetes · Docker · Terraform · AWS · GCP
CI/CD
GitLab CI · GitHub Actions · tests in the pipeline · image scanning · deploy on push
Observability
OpenTelemetry · Prometheus · SigNoz · PostHog
Frontend
React · Next.js · Angular

/experience

Experience · 4.5 years

  1. T-Banknow

    02.2026 — present

    Backend Engineer · T-Segments platform

    • ▸Building a high-load customer segmentation platform: computing and serving audience segments to product teams across tens of millions of customers
    • ▸Designing event-driven streaming segment recomputation (Kafka) — updates in seconds instead of daily batches
    • ▸Optimizing hot read paths (caching, sharding) for tens of thousands of RPS under strict p99 latency SLAs
    GoKafkahighload

  2. Avito

    08.2024 — 02.2026

    Backend Engineer

    • ▸Implemented the B2B platform subscription model with Kafka-based billing → unit revenue +5% in a quarter
    • ▸Introduced compensating transactions → 0 lost payments during downstream outages
    • ▸Launched commercial-offers monetization coordinating 5 adjacent teams → first project revenue
    • ▸Integrated an LLM for auto-generated replies by request category → replies +15%
    • ▸Built the platform's external API for partner-system integrations
    GoKafkabillingLLM

  3. T-Bank

    07.2023 — 07.2024

    Backend Engineer

    • ▸Implemented voice-bot dialog interruption → user retention +22%, NPS growth
    • ▸Designed a Go data-processing service with up to 100K msg/s throughput
    • ▸Built a distributed pipeline with horizontal scaling, replication and load balancing
    • ▸Optimized test infrastructure → automated tests 2x faster, quicker release cycles
    • ▸Built a React monitoring UI for data streams → business requirements shipped 30% faster
    GoReactstreaming

  4. Perfema

    01.2022 — 06.2023

    Fullstack Engineer

    • ▸Built a web app from scratch: architecture, Go backend, React frontend, production deploy
    • ▸Implemented registration, filtered search, moderated reviews and ratings
    • ▸Iterated UX with stakeholders → user engagement +40%
    GoReact

/work

Shipped to production

A call-transcription SaaS — designed, built and deployed solo, from the backend and GPU workers to billing and the site itself.

// available for hire

Need a website or setup, done right?

I'll build your landing page, site or web app and set up deployment and infrastructure — turnkey. Send me the task, I'll scope a solution and quote a price.

  • Landing pages & sites
  • Web apps
  • Deploy & infrastructure
  • Bots & integrations
Discuss a project & price ↗kornachuk.mark@gmail.comI usually reply within a day.

/projects

Academic projects

Master's and team projects — product and analytics, not only code.

/blog

Blog

Long-form project deep-dives: why they exist, how they work inside, where it got hard, and how I solved it.

All posts

/education

Education

/contact

Open to interesting problems in highload and distributed systems — and to turnkey builds.

Message me on Telegram ↗
@potatohd404kornachuk.mark@gmail.comgithub.com/PotatoHD404linkedin.com/in/potatohd