I build systems that survive exponential growth, handle ambiguity, and are resilient to human optimism.

-- KG.

Resume • Blog • Consulting • LinkedIn • GitHub • RubyGems • SlideShare

I’m a lifelong coder with a diverse career, currently a hands-on Staff/Principal-level software engineer and former CTO who builds and delivers reliable, scalable, fault-tolerant systems to production.

My background spans distributed systems, PostgreSQL, Ruby/Rails, infrastructure, developer productivity, and, more recently, applied AI systems: retrieval pipelines, eval harnesses, production automation, and embedding-based services.

I like hard problems with real constraints:

• scaling transactional systems
• eliminating operational risk
• improving developer experience
• shipping AI features without turning the product into a probabilistic mess

• Build and scale large distributed backend systems with strong reliability and observability baked in
• Design production AI workflows around real business use cases
• Improve CI/CD, onboarding, deployment safety, developer productivity, and operational simplicity
• Comfortable in all levels of abstraction, from back-of-the-napkin architecture to nitty-gritty code details.
• Turn messy systems into maintainable ones, and have successfully rewritten systems from scratch in under two months.
• Practice 90%+ test coverage, and it will convince you to do the same.

• Applied AI engineering
• LLM product architecture
• Evaluation-driven development
• Retrieval and ranking systems, in particular Power Law distribution
• PostgreSQL performance, scalability, replication architecture, and security
• Ruby, Python, TypeScript, C/C++, BASH, Rust
• Distributed systems, with high availability, fault tolerance, and auto-healing architectures
• Developer tooling, automated onboarding, and build systems
• Gaming Algorithms, Minimax, Alpha-Beta pruning
• Networking Systems, CISCO routers, VLANs, etc.
• Hardware, ESP32, Arduino, Raspberry PI, and more.

• The silent genius of the DNS protocol — the story of my life. Open Source 2026-07-17
• Deterministic Meets Probabilistic: How I Solved Forms by Writing Four Ruby Gems and Made my Wife Happy AI 2026-07-11
• Qualified.at Is Live: When You Over-Engineer a Form, the Least You Can Do is Launch the Damn Site... AI 2026-07-29
• How I Shipped a Swift CLI in an Hour, with Tests & CI. My First Ever Swift. AI 2026-07-08
• Sopsy: Secrets in Git, Sealed by the Secure Enclave Open Source 2026-06-28
• Evals: The Unit Tests for the Non-Deterministic Parts of Your App AI 2026-06-23
• Evaluating Terraform for DevOps Engineers Software2024-12-06
• Ultra-Fast External SSD Drives: Samsung X5 vs SanDisk Extreme Pro V2 Hardware 2021-06-02
• Yes! It's 2021, and Ruby 3.0, and Ruby on Rails 6.1 are alive and thriving. Are you? Essays2021-01-24
• Turbo Agile™: Optimizing Efficiency of the Engineering Process for Maximum Velocity. Essays2020-09-11
• How to Write Awesome CLI tools in Ruby and test them with RSpec and Aruba Software2020-09-07
• Test your Understanding of Ruby Concurrency Software2020-06-01
• Building IntelliJ Bazel Plugin from Sources Software2020-03-21
• C++ Newbie Tour: Getting Started with C++ on Mac OSX Software2018-09-20
• C5 class instance on EC2: cannot create file: Read-only file system Production2018-05-15
• Dead Simple Encryption with Sym Open Source2017-03-10
• Add a Social Activity Feed for your Site in Minutes with the simple-feed Ruby Gem Open Source2017-02-19
• Building Scalable Performant And Cheap Distributed Applications Part 1 Production2016-05-06
• Mixmax And My First Nodejs App. Software2016-04-07
• Scaling Web Applications On Postgresql A Walkthrough Presentation Production2015-11-28
• Serial Console Hacks With Arduino Hardware2015-11-22
• How To Use Arduino Nano Mini Pro With CH340G On Mac Osx Yosemite Hardware2014-12-31
• Announcing Laser Cutter and MakeABox.IO Open Source2014-11-21
• BORAT: Bathroom Occupancy Remote Awareness Technology with Arduino Hardware2014-10-12
• Arduino IDE Alternatives Hardware2014-08-02
• BackSeat Driver: Autonomous Vehicle Library for Arduino Hardware2014-07-18
• Twelve Step Program For Scaling Web Applications On PostgreSQL Production2014-03-21
• Detangling Business Logic in Rails Apps with PORO Events and Observers Software2013-08-05
• How to configure PostgreSQL for very high read/write throughput Production2013-02-13
• The Case For Vertical Sharding Production2013-02-05
• The Big Switch How We Rebuilt Wanelo From Scratch And Lived To Tell About It Production2012-09-14

A few projects that reflect the range of work I enjoy (the top ones are most recent):

• inquirex — A DSL for building lead qualification forms that gather non-sensitive data, forms that can branch, skip irrelevant questions, compute running totals (such as price of service), and integrate with an LLM to allow the user to describe their relevant situation in their own words, from which LLM extracts structured answers, and skips them later on. The gems are all open source, but they are the basis for the soon-to-be-launched SaaS service @ qualified.at.

• gomoku-ansi-c
  ANSI-C-based game engine for 5-in-a-row (or Gomoku) that runs in a TTY terminal, and you can play using arrow keys.

  Or, you can use the online version running on Google Cloud Run, which offers a ReactJS frontend talking JSON API to a FastAPI Python server with PostgreSQL connectivity, which proxies game moves to a cluster of stateless single-threaded C99/HTTPD backends behind Envoy reverse proxy. Game API includes the entire game state in the JSON hash. You can play the game here: app.gomoku.games

• simple-feed
  Redis-backed social feed architecture similar to Twitter, with O(1) feed read-time property. Scales to tens of millions of users.

• colored2
  Terminal color support for Ruby

• sopsy
  Rust-based wrapper around SOPS, age, and age-plugin-he, which trivially consolidates your dev secrets into .env. encrypted and pushes to git. Now, the killer feature is not just that it encrypts but that it mints the private keys in MacBook Enclave, a secure chip from which nothing can be taken out ever; you unlock it with your thumb. The second killer feature is the fact that it's a chain of individuals with their own private keys, and if you want to join it, you request that you join

• sym in long after active member system review Symmetric encryption via CLI and Ruby API

• puma-daemon
  Puma daemonization support

• cmake-project-template
  C++ / CMake starter project with sensible defaults

• bashmatic
  Bashmatic — 900+ DSL functions written in BASH for readable script feedback, terminal graphics, headers, and more.

• inquirex Family of Gems and NPMJS modules
  A series of MIT-licensed modules for creating sophisticated forms that mulitple rendering formats such as Web, TUI, and suppost a number of LLM keywords.

You can also browse the full collection of public gems written in Ruby here:

• RubyGems profile

I write and speak about:

• PostgreSQL scaling
• Ruby and systems design
• developer productivity
• DevOps and release engineering
• applied AI systems

Some links:

• Inquirex, and what's wrong with today's https://kig.re/speaking?talk=2026.inquirex
• Conference Talks
• Tech Blog
• SlideShare
• LinkedIn

Originally from Kharkiv, Ukraine. Now based in the San Francisco Bay Area.

I graduated Suma Cum Laude from Monash University, majoring in pure mathematics and applied statistics, which permanently damaged my tolerance for fuzzy thinking.

• Agentica Group — parent company of my consulting one
• LinkedIn