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Selected Projects

A curated list of technical challenges I've solved. Delivering robust backend solutions and system integrations across FinTech, Enterprise, and IoT domains.

payments

FinTech & Payments

Payment Gateway Customization

Extensive customization of a major payment gateway. Implemented secure transaction handling, recurring payments, and reconciliation logic.

#Java #Spring Boot #SOAP #OracleDB

M2M Payment Adapters

Designed middleware for communication between payment terminals and SIM top-up services, enabling automated transactions without human intervention.

#IoT #Netty #SecureSockets
dns

Enterprise Systems & Integration

Travel Microservices

Developed scalable microservices exposing Elasticsearch data via REST APIs for a leading global travel management company.

#Java 17 #Spring Boot #Elasticsearch #Docker

Data Box Importer

Automated parsing and ingestion of government data box messages into internal DB. Includes a REST interface for verification.

#XML #Integration #REST

Government Helpdesk

Backend logic for a high-traffic citizen support portal, handling ticket routing and status tracking.

#Spring #Liferay #PostgreSQL
router

IoT & Logistics

Vending Machine Management

Telemetry solution for tobacco vending machines. Server backend for logistics planning + Android app for drivers.

#Android #Java #Logistics

Attendance Terminal

Android-based chip card reader serving as an attendance terminal. Syncs entry/exit data via WebServices.

#Android #Hardware #WebServices
science

Experiments & Open Source

Smart Camera Dashboard

Video stream analysis using OpenCV and YOLO DNN for object detection and license plate recognition.

#ComputerVision #YOLO #OpenCV

Evil Things

A Rust and C based prank toolkit for colleagues who forget to lock their workstations. Manipulates Registry, system sounds, and input via WinAPI.

#Rust #WinAPI #Prank

MidPoint CodeGen

Developer tool automating the generation of boilerplate code via a maven plugin for Evolveum MidPoint Identity Management connectors.

#Java #XML #Codegen

TECHNOLOGIES I WORK WITH

JAVA SPRING KAFKA DOCKER POSTGRESQL AWS