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Projects
Blitz
Single-handedly owned ~20 high-traffic backends end-to-end (77 Elixir umbrella apps, 70+ Redis/50+ PostgreSQL instances) serving ~25k RPS with peaks to 120k for a 7-figure DAU product.
Firezone
WireGuard-based replacement for legacy VPNs. Re-architected and developed key components of the enterprise product. Led infrastructure as code with Terraform on GCP. Open source, YC W22.
eHealth: National Health Service of Ukraine
Co-designed and built the national platform behind reimbursements, EMR, e-prescriptions, and nationwide APIs for clinics and pharmacies. Led architecture, security, hiring, and hands-on Elixir + DevOps. All development open-sourced under Apache license.
Hammer Corp
Advertising platform for thousands of US automotive dealerships: ingests inventory, syndicates ads to major channels (at peak accountable for 30%+ cars on Facebook Marketplace), measures conversion, and collects leads to a unified interface with 24/7 human first-responder reps answering within 60 seconds.
Bullpen - Virtual Sales Floor + CRM
When COVID hit, our sales team lost the buzz of the office. We built a platform that brought it back - a CRM with virtual space where reps could collaborate, learn from each other in real time, and keep the same drive. Then we turned it into a standalone product with AI sprinkled around it.
TalkInto - Omnichannel Messaging Platform and CRM
Messaging/voice backbone powering products like Hammer, Bullpen, and Text2Buy: SMS, voice, various chat integrations, and web chat with clean agent UI and APIs. Features included local numbers, call recording, and routing.
Contractbook
Built the self-service billing system, B2B API and marketing pipeline that let kicked off the business growt.
Financial P2P Marketplace
Architecture and implementation for an institutional P2P lending marketplace for one of Europe's largest lenders ($9B portfolio).
Mbill - P2P Transfers
P2P transfer service for individuals and small-to-medium online merchants. Create a page for your card and share a link to receive payments. Includes customer cabinet, payment button constructor, and transaction reports.
Mastercard MoneySend
Front-end application to receive P2P transfers sent via recipient phone number. Country-wide rollout of phone-number-based transfers.
Forza - PayDay Loan Websites
Front-end, SMS gateway, decision engine, and marketing tools for an online lending originator operating in Moldova, Bosnia, and North Macedonia.
Best Wallet (ex. MBank)
eWallet cloud for worldwide money transfers. For B2C: pay for 2,700+ services across CIS, send money to phone numbers, cash out via partnered banks or cards. For B2B: free SaaS white-label eWallets for banks with simple integration.
IPSP.com - Payment Pages
Responsive landing and payment pages for an Internet Payment Service Provider. Improved conversion on payment flows via lighter UI.
ECommPay - Mobile App
iOS and Android business application for partners to manage payment platform on the go.
Autopayment
Automatically pays for bills based on two types of rules: by threshold of supplier balance (e.g., mobile top-up) or on a periodic basis.
Mobile Cashier
Turns Android devices into payment terminals for deposits and top-ups across numerous service providers, from cellular carriers to credit card loan repayments.
Sage - Sagas Pattern in Elixir
Dependency-free implementation of the Sagas pattern for distributed transactions with explicit compensation. Guarantees that either all transactions complete successfully, or compensating transactions amend partial execution.
LoggerJSON
Structured JSON logging for Elixir with first-class formatters for Google Cloud Logging, Datadog, and Elastic (ECS). Drop-in :logger formatter/handler with runtime config helpers.
Confex
Runtime configuration from environment variables with type casting and adapters (:system, :system_file). 12-factor friendly configuration for Elixir applications.
Elixir Bench
Continuous benchmarking platform for the Elixir ecosystem. Automatically runs performance benchmarks on each commit to detect regressions and track language performance improvements over time. Won Spawnfest 2017 and later accepted into Google Summer of Code.
Annon API Gateway
Configurable API gateway acting as a reverse proxy with a plugin system (ACL, Auth, Validation, CORS, Idempotency), request/response storage, metrics, management UI, and auth provider. Reduces boilerplate across services.
Ecto Mnesia Adapter
Ecto adapter for OTP's built-in Mnesia database that works in the same memory space as the application, providing extremely low latency without deploying a separate database.
Gandalf - Decision Engine
Open-source decision engine SaaS for rule tables, champion/challenger split testing, revision history, decision analytics, and debugging tools.
Man - Template Rendering Engine
Stores iex, mustache, or markdown templates and renders them with localization to HTML or PDF via REST JSON API. Includes an easy-to-use management UI. Free one-click deployment to Heroku.
Vagrant Box OS X
macOS Vagrant boxes for VirtualBox. Run UX tests or build iOS/Mac applications on any machine with a few CLI commands. Used by many teams worldwide, including Boxen.
Parasport - Foundation Portal
Medium-sized web portal for a foundation supporting Paralympic sport, physical rehabilitation, and social adaptation. Built on October CMS.
OneDayOfMine
Storytelling social network that helps see other people's lives through their eyes. Capture moments through the day and share them with descriptions - from special forces in Belarus to a family visit to a film museum in South Korea.
L15 - Night Club x Coworking
Experimental mix of coworking space and a night club ('clubworking') in Kyiv. Turned the office into a best-in-class night club and ran terrace events with world-class DJs every weekend for an entire summer.
Happy Customer
Outsource project to motivate small and medium-sized businesses to provide better customer service via public feedback and simple tracking.
truBrain 1.0
An early-stage product that needed help. I took some swings at UX and performance for free because I wanted to see them make it.
Blog
The Real 10x Engineer
The real multiplier in software isn’t writing more code. It’s judgment: choosing the right problems, avoiding unnecessary systems, and reducing the maintenance burden that slows teams down.
Introducing Sage - a Sagas pattern implementation in Elixir
Distributed transactions are hard and expensive, if you wonder how to pragmatically handle them in a mid-size project - this article is for you.
Run stale tests on file change in Elixir
Mix is an awesome tool but most Elixir beginners are not aware of all its features. mix test --stale is one of them and can make your workflow much better.
Runtime configuration, migrations and deployment for Elixir applications
Shortly after moving from PHP to Elixir I've faced a common issue, the way how do we deploy applications is totally different from the one I'm used to.
National Health Service, on Elixir and Kubernetes
A look at building Ukraine’s national-scale eHealth platform with Elixir, Kubernetes, and pragmatic architecture for reliability and scale.
Bringing blockchain properties to centralized government databases
Making it cryptographically impossible to alter records in a database even with full system access.
Alternative approach for sensitive file uploads
Using signed URLs for secure file uploads directly to cloud storage, bypassing your application servers entirely.
Designing a P2P Lending platform with Elixir in mind
With this post, I want to share with you the design process on one of our latest projects - a P2P marketplace that was intended to be used by hundreds of thousands of users.
$ ls -la ~/projects/ | grep category:other

Projects: Other

Side projects, experiments, and advisory work across various domains.

All AdTech FinTech HealthTech LegalTech Open Source Security Other

Parasport - Foundation Portal

Medium-sized web portal for a foundation supporting Paralympic sport, physical rehabilitation, and social adaptation. Built on October CMS.

  • Accessible content management for non-technical editors
View project →

OneDayOfMine

Storytelling social network that helps see other people's lives through their eyes. Capture moments through the day and share them with descriptions - from special forces in Belarus to a family visit to a film museum in South Korea.

  • Invented and built Instagram before it existed
  • Failed at marketing miserabily and learned in the process
View project →

L15 - Night Club x Coworking

Experimental mix of coworking space and a night club ('clubworking') in Kyiv. Turned the office into a best-in-class night club and ran terrace events with world-class DJs every weekend for an entire summer.

  • 1,500-person peak events
  • Created a novel format of club-working
View project →

Happy Customer

Outsource project to motivate small and medium-sized businesses to provide better customer service via public feedback and simple tracking.

View project →

truBrain 1.0

An early-stage product that needed help. I took some swings at UX and performance for free because I wanted to see them make it.

View project →
Navigation
Home
gh
About
ga
Projects
gp
Blog
gb
Contact
gc
Projects
Blitz
Single-handedly owned ~20 high-traffic backends end-to-end (77 Elixir umbrella apps, 70+ Redis/50+ PostgreSQL instances) serving ~25k RPS with peaks to 120k for a 7-figure DAU product.
Firezone
WireGuard-based replacement for legacy VPNs. Re-architected and developed key components of the enterprise product. Led infrastructure as code with Terraform on GCP. Open source, YC W22.
eHealth: National Health Service of Ukraine
Co-designed and built the national platform behind reimbursements, EMR, e-prescriptions, and nationwide APIs for clinics and pharmacies. Led architecture, security, hiring, and hands-on Elixir + DevOps. All development open-sourced under Apache license.
Hammer Corp
Advertising platform for thousands of US automotive dealerships: ingests inventory, syndicates ads to major channels (at peak accountable for 30%+ cars on Facebook Marketplace), measures conversion, and collects leads to a unified interface with 24/7 human first-responder reps answering within 60 seconds.
Bullpen - Virtual Sales Floor + CRM
When COVID hit, our sales team lost the buzz of the office. We built a platform that brought it back - a CRM with virtual space where reps could collaborate, learn from each other in real time, and keep the same drive. Then we turned it into a standalone product with AI sprinkled around it.
TalkInto - Omnichannel Messaging Platform and CRM
Messaging/voice backbone powering products like Hammer, Bullpen, and Text2Buy: SMS, voice, various chat integrations, and web chat with clean agent UI and APIs. Features included local numbers, call recording, and routing.
Contractbook
Built the self-service billing system, B2B API and marketing pipeline that let kicked off the business growt.
Financial P2P Marketplace
Architecture and implementation for an institutional P2P lending marketplace for one of Europe's largest lenders ($9B portfolio).
Mbill - P2P Transfers
P2P transfer service for individuals and small-to-medium online merchants. Create a page for your card and share a link to receive payments. Includes customer cabinet, payment button constructor, and transaction reports.
Mastercard MoneySend
Front-end application to receive P2P transfers sent via recipient phone number. Country-wide rollout of phone-number-based transfers.
Forza - PayDay Loan Websites
Front-end, SMS gateway, decision engine, and marketing tools for an online lending originator operating in Moldova, Bosnia, and North Macedonia.
Best Wallet (ex. MBank)
eWallet cloud for worldwide money transfers. For B2C: pay for 2,700+ services across CIS, send money to phone numbers, cash out via partnered banks or cards. For B2B: free SaaS white-label eWallets for banks with simple integration.
IPSP.com - Payment Pages
Responsive landing and payment pages for an Internet Payment Service Provider. Improved conversion on payment flows via lighter UI.
ECommPay - Mobile App
iOS and Android business application for partners to manage payment platform on the go.
Autopayment
Automatically pays for bills based on two types of rules: by threshold of supplier balance (e.g., mobile top-up) or on a periodic basis.
Mobile Cashier
Turns Android devices into payment terminals for deposits and top-ups across numerous service providers, from cellular carriers to credit card loan repayments.
Sage - Sagas Pattern in Elixir
Dependency-free implementation of the Sagas pattern for distributed transactions with explicit compensation. Guarantees that either all transactions complete successfully, or compensating transactions amend partial execution.
LoggerJSON
Structured JSON logging for Elixir with first-class formatters for Google Cloud Logging, Datadog, and Elastic (ECS). Drop-in :logger formatter/handler with runtime config helpers.
Confex
Runtime configuration from environment variables with type casting and adapters (:system, :system_file). 12-factor friendly configuration for Elixir applications.
Elixir Bench
Continuous benchmarking platform for the Elixir ecosystem. Automatically runs performance benchmarks on each commit to detect regressions and track language performance improvements over time. Won Spawnfest 2017 and later accepted into Google Summer of Code.
Annon API Gateway
Configurable API gateway acting as a reverse proxy with a plugin system (ACL, Auth, Validation, CORS, Idempotency), request/response storage, metrics, management UI, and auth provider. Reduces boilerplate across services.
Ecto Mnesia Adapter
Ecto adapter for OTP's built-in Mnesia database that works in the same memory space as the application, providing extremely low latency without deploying a separate database.
Gandalf - Decision Engine
Open-source decision engine SaaS for rule tables, champion/challenger split testing, revision history, decision analytics, and debugging tools.
Man - Template Rendering Engine
Stores iex, mustache, or markdown templates and renders them with localization to HTML or PDF via REST JSON API. Includes an easy-to-use management UI. Free one-click deployment to Heroku.
Vagrant Box OS X
macOS Vagrant boxes for VirtualBox. Run UX tests or build iOS/Mac applications on any machine with a few CLI commands. Used by many teams worldwide, including Boxen.
Parasport - Foundation Portal
Medium-sized web portal for a foundation supporting Paralympic sport, physical rehabilitation, and social adaptation. Built on October CMS.
OneDayOfMine
Storytelling social network that helps see other people's lives through their eyes. Capture moments through the day and share them with descriptions - from special forces in Belarus to a family visit to a film museum in South Korea.
L15 - Night Club x Coworking
Experimental mix of coworking space and a night club ('clubworking') in Kyiv. Turned the office into a best-in-class night club and ran terrace events with world-class DJs every weekend for an entire summer.
Happy Customer
Outsource project to motivate small and medium-sized businesses to provide better customer service via public feedback and simple tracking.
truBrain 1.0
An early-stage product that needed help. I took some swings at UX and performance for free because I wanted to see them make it.
Blog
The Real 10x Engineer
The real multiplier in software isn’t writing more code. It’s judgment: choosing the right problems, avoiding unnecessary systems, and reducing the maintenance burden that slows teams down.
Introducing Sage - a Sagas pattern implementation in Elixir
Distributed transactions are hard and expensive, if you wonder how to pragmatically handle them in a mid-size project - this article is for you.
Run stale tests on file change in Elixir
Mix is an awesome tool but most Elixir beginners are not aware of all its features. mix test --stale is one of them and can make your workflow much better.
Runtime configuration, migrations and deployment for Elixir applications
Shortly after moving from PHP to Elixir I've faced a common issue, the way how do we deploy applications is totally different from the one I'm used to.
National Health Service, on Elixir and Kubernetes
A look at building Ukraine’s national-scale eHealth platform with Elixir, Kubernetes, and pragmatic architecture for reliability and scale.
Bringing blockchain properties to centralized government databases
Making it cryptographically impossible to alter records in a database even with full system access.
Alternative approach for sensitive file uploads
Using signed URLs for secure file uploads directly to cloud storage, bypassing your application servers entirely.
Designing a P2P Lending platform with Elixir in mind
With this post, I want to share with you the design process on one of our latest projects - a P2P marketplace that was intended to be used by hundreds of thousands of users.