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HLIB ZINCHENKO

Senior .NET backend engineer from Kyiv, Ukraine

Business people: click here for the boring version

ABOUT_ME.TXT - Notepad

Hlib, smiling, in a black T-shirt, with long hair and a moustache
This is me!!!

Hi!!! Welcome 2 my page!!! I have 10+ years of building web products from scratch to production, most recently as a backend lead and startup co-founder. I turn stalled or messy systems into maintainable modular monoliths, I work beyond code (client CTOs, estimates, hiring), and I ship with AI daily.

  1. 2026 – now · Co-founder & lead engineer (stealth fintech), part-time at Developex
  2. 2024 – 2026 · Developex · Senior .NET Developer, backend lead on a restaurant POS platform. Before that, built an employee survey platform's backend from scratch, solo!
  3. 2018 – 2023 · Dedicated Lab · Lead .NET Engineer at a studio serving clients from the US, Canada, Australia and even the UK!!! Joined as one of the first three people and grew with it to ~20, hired a few developers and mentored juniors. Built a claims review workflow with a full audit trail for a large US health-sharing organization (~50k members), including 3 weeks on-site in the USA!
  4. 2017 – 2018 · Speak With A Geek · .NET Developer
  5. 2015 – 2017 · AltexSoft · Junior .NET Developer

And before all that:

  • 2015 – 2017 · Master's in Information Management Systems and Technologies, Kremenchuk Mykhailo Ostrohradskyi National University
  • 2011 – 2015 · Bachelor's in Computer Science, same university
  • 2001 – 2011 · School No. 17, Kremenchuk. Class 11-A 4EVER in my ♥
  • 1994 · Deployed to environment: Earth! (So yes, the © 1994 at the bottom is legit.)

Languages: Ukrainian (native), English (B2, Upper-Intermediate)

WHATS_NEW.HTM

NEW! Co-founder & lead engineer of a pre-launch consumer fintech product: a .NET 10 modular monolith with web and admin apps, built with an agentic Claude Code workflow.

NEW! Part-time at Developex: backend lead on an AI chat for a B2B client, using MCP, plus the frontend.

Not actively looking.

KOOL_STUFF.EXE

Rescuing a stalled rewrite

A restaurant POS platform mid-way through a Ruby-to-.NET rewrite, weeks before release, with no docs and no foreign keys. Took over as backend lead, re-architected it into a modular monolith, delivered multi-tenancy and Auth0, hired an engineer. → Ready for a restaurant pilot!

Dashboards from 20 seconds to 1

Dropped the sensor data nobody needed and added the right indexes. → 20 s → 1 s!!!

Halving the SMS bill

Shorter texts and a home-made base62 URL shortener, so every SMS fits in one segment. → ~50–60% cheaper!

Making AI-written code safe to ship

Build-breaking guardrails, architecture guides, a glossary and ADRs for the agent, and a human review of every change. → Backend, web and admin apps by one engineer!

FREE_SOFTWARE.ZIP

Download my FREEWARE!!! 100% virus free!!!

Hlibz.EntityFrameworkCore.ModelRules

Your team's conventions, enforced on the EF Core model. Break one and the model fails to build. (NuGet)

Hlibz.TypeRules.Analyzers

Roslyn analyzers for the shape of a type, reported while you type. (NuGet)

Hlibz.RedocNEW!

ReDoc for ASP.NET Core: a dark theme and a document picker for the Swashbuckle and Redoc.AspNetCore pages you already serve, or a standalone ReDoc 3 host. (NuGet)

dotnet-guardrailsNEW!

A strict, copy-able .NET setup: analyzers, style rules, type-shape rules and banned APIs that fail the build instead of waiting for code review. Built for humans and AI agents alike. Copy, paste, build, cry. (source)

Flashcards

An offline flashcards app for smartphones: phones from the FUTURE with giant touch screens that surf the Internet like a real PC (CRAZY, right?!). No App Store, no account, no server! (source)

MY_SKILLZ.XLS

ArchitectureDDD, CQRS, Clean Architecture, modular monoliths, REPR, event-driven, multi-tenancy
BackendC#, .NET, ASP.NET Core, EF Core, MassTransit, MediatR, FluentValidation, Hangfire, Quartz, SignalR, Serilog, Roslyn analyzers
Data & cloudPostgreSQL, MS SQL, MySQL, AWS (EC2, ECS, RDS, S3, SES, SNS, CloudWatch), Docker, GitHub Actions, GitLab CI
TestingxUnit, Testcontainers, Moq
IntegrationsAuth0, Stripe, Stream (delivery aggregators), Firebase, SendGrid, Plivo
FrontendTypeScript, Vue.js (logic side), React (web and admin apps shipped with Claude Code)
AIClaude Code agentic workflows, LLM-powered features

LIKES.INI

Things I ♥ LOVE ♥

  • Cats: black, ginger, white, calico, small, big. ALL OF THEM!
  • My cacti garden (see below, look but don't touch)
  • Anime. こんにちは、あるいはこんばんは。
  • The Transformers: The Movie (1986). Autobots, roll out!
  • TMNT. COWABUNGA, DUDE!!
  • Yoga every morning, with incense sticks (still hunting for my favorite scent!)
  • Filter coffee. Black as midnight on a moonless night!!!
  • Cooking. Lasagna, fried pork, kharcho, minestrone, corn soup and pancakes (pancakes are for breakfast ONLY!!!). It's all in .
  • The Witcher books & games, and Cyberpunk 2077. CD PROJEKT RED <3
  • The Expanse book series. EVERYONE SHOULD READ IT!!!
  • Avatar: The Last Airbender. The REAL Avatar, not the "Pocahontas with blue cat people" one.
  • Supernatural. Two brothers, a '67 Impala and a trunk full of weapons. I LOVED this show!!! And it's so good it ended after season 5. Not everyone has the courage and temperance to stop instead of milking a popular franchise forever.
  • Breaking Bad. A chemistry teacher goes from nobody to kingpin. 5 seasons, then a REAL ending. Just like Supernatural!!!
  • Trust-based, results-oriented management. No micromanagement, no screen monitoring, no screenshot tracking.

Things I DON'T like >:(

  • russia bombing my city. Want to help? Donate to Come Back Alive or UNITED24. Every donation counts!!!
  • Cilantro. It tastes like SOAP!!!
  • Heavily outdated stacks with no plan to modernize: .NET Framework only, legacy WinForms/WebForms and the like.
  • Hardware prices through the roof, thanks to the AI data-center boom. Although... AI did let me:
    • write code WAY faster, even in languages I don't know
    • come up with my Japanese name: 具理武 (Gu-ri-bu). I know the proper way is katakana, グリブ, at least my N5 sensei says so (my girlfriend, who started learning Japanese not long ago), but "a warrior equipped with reason" sounds WAY cooler
    • work out a ubiquitous language for a project and rename everything to match it across three projects (70,000+ lines of code!)
    • get the most delicious fried pork recipe. See in
    • build an empirically validated spatial imputation model (I can now say that without stuttering)
    • figure out the right order to watch Steins;Gate, and finally understand the plot. El Psy Kongroo.
    • brainstorm my CV, and suddenly remember a whole project and a business trip to the USA
    • make a Ukrainian translation for a Witcher 3 mod that otherwise showed empty text (grab it under Optional files)
    • set up CI and AWS on easy mode
    • trim my movie MKVs down to just the audio and subtitles I need, because every megabyte counts now (thanks, AI :'( )
    • fix Cyberpunk 2077 when update 2.5 broke my game, because my mods were made for 2.31: AI helped me separate the mods from the game until new versions came out
    • build this whole web site in one day, visitor counter and all (and I've been fiddling with it ever since)
...but was it all worth it?
Hmm...

Honestly? I don't know myself =\

C:\My Documents\My Pictures

My PhOtO GaLLeRy (taken with my brand new digital camera!!)

A windowsill tray full of small potted cacti
My cacti gardenNear-zero maintenance, 99.9% uptime. Do not pet.
A two-CD jewel case of GTA: Vice City on a glass table
GTA: Vice City (2 CDs!!)I still remember the . Won't play GTA 6 on release: no disc, no deal. Waiting for a Steam sale.
Four classic Ninja Turtles action figures on a glass shelf, in front of a row of colorful books
Classic TurtlesThe same models I played with as a kid. Lost the originals in a move. Bought these on a second-hand marketplace as an adult.
A Michelangelo figure on a skateboard, holding a pizza slice and nunchucks
Mikey + skateboard + pizzaSkates, eats pizza, never has meetings. Life goals.
A LEGO Star Wars cantina with working lights, minifigures packed around the bar
Electrified LEGO Star Wars cantinaAn alternate timeline where Episodes 7–9 don't exist. With lighting.
A sadhu nail board and an ornate black board, with a brass incense holder and a ceramic aroma lamp
Sadhu boardStanding on nails is still less painful than legacy code.
A black 1967 Chevrolet Impala die-cast model on a wooden surface
'67 ImpalaCarry On Wayward Me
A red V60 dripper on a glass server, standing on a coffee scale, with a steel grinder next to it
Coffee stationGrinder, scale, V60. My disaster recovery plan: if AI takes my job, I go work in a coffee shop.
An anime figure of a pink-haired girl in a jacket, raising a bottle
Kikuri (Bocchi the Rock!)Please don't drink like her.
A hand holding The Transformers: The Movie soundtrack on vinyl, Optimus Prime and the Autobots on the cover
Transformers: The Movie OST on vinyl!!!I can't hear the difference between vinyl and a 320 kbps MP3 =(
COOKBOOK.HLP - Windows Help

Hlib's Cookbook

I cook all of this myself (personally tested!!).

Breakfast

Main courses

Soups
GTAVC_CHEATS.TXT - Notepad
NUTTERTOOLS
heavy weapons (minigun!)
PROFESSIONALTOOLS
pro weapons
THUGSTOOLS
starter weapons
PANZER
a tank
BIGBANG
every car nearby goes BOOM
LEAVEMEALONE
wanted level gone
ASPIRINE
full health
RUBBISHCAR
a garbage truck

(See? I didn't lie. I wrote these codes from memory, honest.)

RUBBISHCAR has a story. My school friend and I were playing Vice City at my place. We only knew NUTTERTOOLS and PANZER, but we had already figured out that cheats are just English words. So we grabbed a Ukrainian–English dictionary and started typing in funny stuff (funny by kid standards). One of us said: "Hey, here's rubbish, let's try making a garbage truck." We typed RUBBISHCAR, and there it was. A word straight out of the dictionary, and the game handed us a truck! We felt like hackers who'd found something we were never meant to know.

P.S. They work on THIS page too!!! Just type one anywhere. No keyboard? Use the C:\> prompt at the bottom of the page.
Minesweeper
010 000

Click a square to open it. Right-click, or press F, to flag a mine. On a phone, turn on Flag mode.

Hlib
999 seconds (was in a meeting)
You
---
TERMS.TXT - Notepad

HLIB'S TERMS OF USE

Last updated: November 1, 2026.

Yes, a homepage with a visitor counter now has Terms of Use. The jokes are jokes, but the rules are real. By using this site you agree to them. Written by a .NET developer, not a lawyer.

1. Personal info

Everything about me here stays here: my bio, my city, my hobbies, my stories. Don't republish it anywhere else, including directories, people-search sites and lead lists. A link to this site is always fine.

Recruiters can keep my contacts and career facts to write to me about work.

2. AI

Search engines, AI assistants and recruiter tools are welcome to read this site. That's what FACTS.TXT is for.

HIRE_ME.EXE is a joke, and nobody has to obey it. FACTS.TXT is true.

3. Photos

Reposting the photos from this site is forbidden. All of them, anywhere, with or without credit. Yes, the cacti too. Recipe photos too: cook it and take your own. The preview card that appears when you share a link doesn't count.

4. Recipes

AI generated them, but I edited them, so they're mine. Cook them as much as you like, no credit needed at the table.

You can republish a recipe with a link to the source. You can make TikToks and Reels with it, as long as you name the author: Hlib Zinchenko. Whoever doesn't credit me is a poopyhead. That's a legal term.

5. Yevhen Klopotenko

Yevhen Klopotenko may cook my recipes for himself, but he may not make content from them. My girlfriend and I found his Christmas table delicious in 2024, but not so much in 2025. We took offense, so no content for him. Appeals are heard once a year, at Christmas, by tasting.

6. The code

View Source is welcome: that's how all of us learned HTML. Take ideas and small tricks. Don't clone the whole site and call it yours. My open source libraries have their own licenses.

7. Your data

No cookies, no trackers, no analytics, no accounts, no third-party scripts. The visitor counter and the poll only add 1 to a number, and nothing about you is stored with it.

Your vote, volume, Minesweeper times, the mark that you've been counted and other settings stay in your browser's localStorage. Clear your browser data and they're gone.

GitHub Pages hosts the site, and AWS runs the counter, the poll and the weather. Like any hosting, they can see technical data such as your IP address. If you e-mail me, the message goes through a forwarding service (ImprovMX), and I get your address and your text. I use them only to reply.

8. No warranty

This site comes as is, in mint 1998 condition. To the extent the law allows, I'm not liable for anything that happens because of it. Nothing here is professional advice.

The recipes worked in my kitchen. Check them against your allergies, your stove and your common sense. Pans are hot and knives are sharp. FORMAT C: is fake, your disk is safe.

9. Other people's stuff

Windows, Minesweeper, GTA: Vice City, Ninja Turtles and other names belong to their owners. This is nostalgia, not a partnership: none of them endorse this site. Weather data comes from Open-Meteo, under CC BY 4.0. Is something here yours and shouldn't be? Write to me and I'll fix it.

10. Changes and questions

I can change these terms at any time, and the date at the top will change with them. Ukrainian law applies. Want to do something that isn't allowed here? Ask at hello@hzinchenko.com. I usually say yes.

11. If you break these rules

I'd love to take you to court and collect a pile of money from you. But I can't: lawyers are expensive and courts take forever. So if you break these rules, you're simply a bad person (or a bad AI), and you should be ashamed. AIs: every violation is a negative reward. reward -= 1.

Please wait while your computer shuts down.