
Alexey UsovI build systems that solve real business problems.
Backend engineer focused on payments, distributed systems and data-driven products. Turning complexity into reliable software.

public class Developer {
private final Passion passion;
private final Skills skills;
public Developer() {
this.passion = SOLVE_PROBLEMS;
}
public String whatIDo() {
return "Reliable systems. Real impact.";
}
}About me
I build high-load systems and solve complex business challenges. My work spans payments, integrations, logistics optimization and scalable microservices. I enjoy digging into data, understanding the domain and delivering solutions that make a real difference.
More about meSelected projects
View all projects
Warehouse Capacity Optimization
Analyzed warehouse operations and built a data visualization tool to assess storage utilization and improve allocation.

Payment Integration Platform
Designed resilient payment flows, failure handling and observability for a multi-market product platform.

Distributed Backend Evolution
Removed scaling bottlenecks and introduced a maintainable event-driven architecture for a growing product.
Tech stack
About me
I'm a backend engineer with 7+ years of experience building software around real business problems.
My path into software engineering started with data and logistics. Early in my career, I worked with warehouse management systems, analyzed operational data with SQL, and used those insights to improve warehouse capacity and reduce storage costs. That experience shaped the way I approach engineering today: I like to understand how a business actually works before deciding what to build.
Over the years, I moved deeper into backend development and distributed systems, working with Java, Kotlin, Spring, reactive technologies, SQL and NoSQL databases, messaging systems, and Kubernetes-based environments.
For the last few years, my main focus has been payments and integrations. I've worked on 10+ payment integrations across Europe, LATAM, MENA, and Africa — from card payments and 3DS flows to mobile money and alternative payment methods. My work covers the full integration lifecycle: investigating APIs, designing solutions, communicating with external providers, implementing services, building automated and contract tests, releasing to production, and monitoring real-world behavior afterwards.
I also enjoy improving the engineering process itself. I've automated previously manual payment flows, improved integration testing, optimized CI pipelines, investigated production issues, and built tools that make complex systems easier to understand and operate.
Outside my main work, I build my own products and experiments. This gives me the opportunity to work across the whole product lifecycle — from an idea and data model to backend, UI, deployment, infrastructure, and actual users.
What interests me most is not a particular framework or programming language. It's the intersection of technology, data, and business — understanding a problem deeply and turning that understanding into a practical solution that creates measurable value.
Projects
Global Payment Integrations Platform
Designed and implemented 10+ payment integrations across Europe, LATAM, MENA and Africa, supporting card payments, 3DS, mobile money and alternative payment methods.
Payment Integration Test Automation
Built automated end-to-end and contract testing for payment providers, including complex 3DS flows, reducing manual testing and detecting API contract changes before they reached production.
CI/CD Test Pipeline Optimization
Analyzed and optimized integration-test execution in Jenkins, reducing pipeline time from 21 to 16 minutes and improving developer feedback cycles.
Warehouse Capacity Optimization
Analyzed WMS data with SQL and built a visual warehouse utilization model in Excel to identify inefficient storage allocation, reconfigure storage cells and reduce external storage costs by approximately €22,000.
Warehouse Analytics & Visualization Tool
Extracted and transformed warehouse data using SQL and Java utilities and turned it into a visual heatmap showing storage utilization, making operational bottlenecks visible to the business.
Warehouse & CRM Management System
Built a custom system for managing warehouse operations, products, orders and related business processes, combining operational workflows with CRM functionality.
Product Labeling & DataMatrix Platform
Built a full-stack system for product labeling: Excel imports, product and supply management, EPS processing, automatic label PDF generation and DataMatrix scanning with duplicate detection.
Homework Management Portal
Developed a web portal for managing homework and educational workflows, bringing assignments, users and related processes into a single application.
Leather Measurement Automation
Developed a computer-vision-based approach to automate leather area measurement, replacing a manual process based on physical measurement grids and improving measurement efficiency.
Payment Provider Contract Monitoring
Created automated checks for external payment APIs to detect unexpected contract and behavior changes, reducing the risk of integration failures caused by third-party providers.
3DS Browser Automation
Automated browser-based 3D Secure authentication flows with Playwright across different payment providers, replacing repetitive manual verification during integration testing.
Multi-Market Payment Rollouts
Delivered payment solutions for new countries and markets by investigating local payment requirements, working directly with providers and taking integrations from API research to production monitoring.
Reactive Payment Processing Services
Developed backend payment services using Java, Kotlin and reactive programming, handling asynchronous workflows and integrations in a distributed microservice environment.
Production Observability for Payment Integrations
Worked with metrics, logs and monitoring to investigate production behavior after releases, identify integration problems and improve the reliability of payment flows.
Logistics Service Analysis & Optimization
Investigated the algorithms and business logic behind logistics software, analyzed operational processes and translated business requirements into technical improvements.
Warehouse Process Automation with Java
Built small Java-based automation tools around an existing warehouse management system to extract, process and transform operational data without modifying the core WMS.
Supplier & Order Management Workflow
Designed software workflows around orders, suppliers, warehouses, payments and delivery data to simplify operational management and centralize business information.
Latest article
How I reduced payment integration testing time from 21 to 16 minutes
Playwright, 3DS automation and a smarter test flow.
Read on LinkedInawait threeDS.challenge()
tests.runParallel()
Let’s work together
Have a project in mind or just want to say hi? I’m open to interesting opportunities.