Maksym

MAKSYM FEDENKO
Java Backend Engineer
Vinnytsia, Ukraine | [відкрити контакти](див. вище в блоці «контактна інформація») | [відкрити контакти](див. вище в блоці «контактна інформація»)
[відкрити контакти](див. вище в блоці «контактна інформація») | t.me/fedich_m

SUMMARY:
Java Backend Engineer with 5 years of commercial experience building and maintaining backend systems in
Java, Spring Boot and Hibernate, including REST APIs, microservices, Kafka and AWS. Worked in billing,
EdTech (CRM for schools and universities) and car rental domains, with a strong focus on test coverage and
legacy system maintenance. Use AI-assisted development daily (Claude Code, spec-driven development).
Looking for a backend role on a product team where I can own features end to end and ship reliable, well-tested
services.

SKILLS:
• Programming Languages: Java (8-17), TypeScript, Go (test tooling)
• Frameworks: Spring Boot, Spring Framework, Spring MVC, Spring Data JPA (JPA/ORM), Hibernate
• APIs & Architecture: REST API / RESTful Web Services, Microservices Architecture
• Messaging: Apache Kafka
• Databases: PostgreSQL, MySQL
• Cloud: AWS
• Testing: JUnit, Mockito
• Tools: Git, Maven, Gradle, IntelliJ, VS Code
• DevOps: Docker, GitLab CI, Nginx, CI/CD
• AI-Assisted Development: Claude Code (spec-driven development), AI coding agents as part of daily
workflow
• Languages: English - B2 (Upper-Intermediate), Ukrainian - native

EXPERIENCE:
Java Backend Engineer | ONSEO | November 2023 - September 2026
• Implemented new billing features in microservices application using Java and Spring Boot in a multinational
team, ensured 90% test coverage;
• Used AWS S3 for file storage and AWS Secrets Manager for key management in the microservices
application;
• Investigated existing system functionality and documented it on Confluence for better team understanding;
• Developed internal REST API dedicated to supporting testing processes.
Tech stack: Java 17, Maven, Spring Boot, MySQL, Kafka, AWS, Mockito, Splunk, Git
Java Backend Engineer | VARTEQ Inc. | October 2022 - September 2023
• Improved and extended a large legacy School/University CRM system based on Java 8 and Struts by using
reverse engineering to understand the codebase
• Implemented new functionality and documented system behavior
• Presented newly developed features directly to the customer
Tech stack: Java 8, Struts 1.3, Maven, JAX-RS, MSSQL, Wildfly, Git
Java Backend Engineer | Capgemini Engineering | December 2021 - October 2022
• Contributed to the development of a car rental service by designing clear and efficient APIs based on
business requirements
• Optimized SQL queries to improve REST API response time and implemented hotfixes during critical
moments to enhance user experience
• Increased test coverage to improve system stability and reliability
Tech stack: Java 11, MyBatis, Flyway, JUnit, Mockito, Elasticsearch, Spring Framework, Microsoft Azure

Java Backend Engineer | SoftServe | January 2021 - December 2021
• Contributed to the team's migration of a service to the cloud, mainly by writing tests
• Cut QA testing time by up to 40% by building a CSV comparison service with an automated pipeline from
scratch
Tech stack: Java 8, Spring Framework, Hibernate, JUnit, Mockito, Git

PROJECTS:
uptime-hero - Personal SaaS Project (in development)
• Building a lightweight website-uptime monitoring SaaS from the ground up, covering backend architecture,
checking logic, and notification flow
• Prioritized making the core uptime-checking engine reliable and thoroughly tested before layering on
additional features
• Built a separate configurable Go-based test service to simulate error codes and failure scenarios, used to
load-test the uptime checker at 1000+ concurrent requests
• Using Claude Code in a spec-driven workflow to build the frontend, referencing established products like
UptimeRobot for UX
Tech stack: Java, Go, TypeScript, Docker, Claude Code

EDUCATION:
2020 - 2021 | Mate academy
Computer Software Engineering Certificate
2012 - 2016 | National Technical University Of Ukraine “Kyiv Polytechnic Institute”, Kyiv
Bachelor’s Degree in Foundry Engineering