UA

About

Six years of backend work - payment systems, a B2C product built from scratch, and government digital services: from privatization auctions on Prozorro.Sale to digitizing ecology services. I've worked with legacy code and with things built from scratch.

When a client just hands me a problem, with no solution in mind, I write up the requirements myself. I've led a team of low-code developers - assigning tasks, reviewing their work, mentoring.

Skills

Daily use

  • PHP
  • Yii2
  • Python
  • REST API
  • MySQL / PostgreSQL
  • Git

Comfortable, not daily

  • Node.js
  • JavaScript
  • HTML/CSS
  • jQuery

Data & infra

  • Elasticsearch
  • Memcached
  • Redis

Systems & IoT

  • Linux
  • Bash/SSH
  • WebSocket

Other tools

  • BPMN process schemas
  • CI/CD

Experience

  1. Software Engineer

    Dropla (formerly Moohii until Nov 2024)

    Aug 2023 - Present

    Government digital services (Ecology, GovTech)

    • Built the backend for a personal digital-services portal on an architecture based on Diia: 3 microservices, integrated with government registries (Forests of Ukraine, the Unified State Register) to check company ownership. The program's biggest service - licensing for hazardous-waste management.
    • Wrote backend logic for a BPMN-based process engine: business processes are defined as JSON node schemas, rendered by the frontend as step-by-step flows.
    • Led a team of low-code developers - assigned tasks, reviewed process logic, mentored.
    • Often gathered requirements myself, straight from non-technical people on the government side, moving fast because things were needed yesterday. Basically an extra business-analyst role on top of coding.

    Drone mapping & GPS-denied navigation R&D

    • Built a Python service turning drone thermal and RGB images into geo-referenced orthophoto maps for humanitarian demining, 1-2m accuracy.
    • Did GPS-denied navigation R&D: tried ORB-SLAM3 (didn't work out), built a sensor-fusion prototype on a Raspberry Pi 4, and handed off a report that set the team's next direction.

    AI messenger platform

    • Contributed to a B2B SaaS platform integrating AI assistants into Telegram, Instagram, WhatsApp, and a web widget - multi-service Python architecture with a client-facing admin panel.
    • Node.js
    • Python
    • Microservices
    • BPMN
    • OpenDroneMap
    • Raspberry Pi
  2. PHP Developer

    Brilliant IT

    Oct 2022 - Sep 2023

    • Took over an old auction platform (built on Prozorro.Sale) where the architecture was broken almost everywhere - business logic in views, broken ActiveRecord patterns, tons of dead code. Refactored it bit by bit while working on new tasks.
    • Replaced unsafe raw SQL with parameterized queries across roughly 300k auction records - closed security gaps and improved performance.
    • Built a separate service to verify participants' bid documents signed with a qualified electronic signature (KEP) - checked the applications and handed the operator the original signature file plus all the signature details.
    • Expanded search with Elasticsearch - added new searchable fields and made it faster.
    • PHP
    • Yii2
    • Elasticsearch
    • MySQL
    • PostgreSQL
  3. PHP Developer

    Smile Expo

    Mar 2021 - Aug 2023

    • Designed the database architecture and backend from scratch for a B2C search product that shipped to production.
    • Built full-text search with filters on custom SQL queries (no third-party search engine) - the best results showed up first. Optimized for load, proposed an Elasticsearch migration.
    • Added multi-language support (3 languages) with simultaneous multi-language form validation - fixed a gap in how Yii2 validates forms.
    • PHP
    • Yii2
    • MySQL
    • Memcached
  4. PHP Developer

    JP Technology Group

    May 2020 - Mar 2021

    • Built a shared interface for connecting 3+ payment systems, including crypto exchanges - each new provider plugged in as its own class, no changes to the core payment logic.
    • Protected payment operations from running twice, so duplicate webhooks or provider retries couldn't double-charge someone.
    • Built admin-panel tools for the ops team: transaction filtering, manual approve/refund, reconciling totals with the provider.
    • PHP
    • Yii2
    • MySQL
    • Bootstrap
    • React

Typeface: e-Ukraine by the Ministry of Digital Transformation of Ukraine, CC BY 4.0.

© 2026 Vladyslav Yunak