Oleksandr Kolomoiets

I build products from the data model up.

Backend developer from Ukraine, working on data infrastructure: Go, PostgreSQL, Elasticsearch, Kafka. Outside my day job I build products end to end, from the schema to the server they run on. Here are five of them, with the decisions that shaped each one.

Products

Source code is private. I can walk you through the architecture and code on a call.

  • zbc.wtf

    Live, in active development

    A multiplayer first-person shooter that runs in the browser, with an authoritative Go game server, a full meta-game platform around it, and client prediction kept honest by a shared test suite.

    Go, TypeScript, React, Three.js, MongoDB, Redis, Prometheus

  • Komirne

    Live at komirne.app

    A web app and Telegram bot that helps landlords track utility bills for rented flats. A photo of a meter becomes a reading, a bill and a tenant balance.

    Go, PostgreSQL, htmx, Claude API, Telegram Bot API, Caddy

  • Vervechka

    Design stage, preparing a pilot

    A platform for small private schools in Ukraine. Parents see their child's day, photos, menu and payments; the school runs contracts, invoices, the class journal and communication.

    Go, PostgreSQL, River, React, React Native (planned)

Open source

Code is public on GitHub.

  • claude-memory

    Open source, Apache 2.0

    Shared, curated long-term memory for Claude Code. One Go binary stores facts in PostgreSQL with pgvector and feeds the relevant ones back into each prompt within an 800 ms budget.

    Go, PostgreSQL, pgvector, Ollama (bge-m3), MCP

  • Dev Digest

    Open source, course project

    A local-first studio for AI pull-request review. I took a course starter template and extended it with more than 150 commits of features, evals and CI.

    TypeScript, Fastify, Next.js 15, Drizzle, PostgreSQL, pgvector, LLM APIs, MCP