Dmytro

DMYTRO KAZMIRUK
JAVA SOFTWARE ENGINEER

Work experience
Lviv, Ukraine
February 2024 - Present (2 years)
Calaton Systems
[open contact info](look above in the "contact info" section) Corvus Link – SaaS platform that helps businesses solve problems and build
resilience
[open contact info](look above in the "contact info" section) Developed RESTful APIs in Spring Boot serving 10k+ users, focusing on security
(Spring Security, OAuth2) and performance optimization.
Integrated OpenAI API to deliver AI-driven features, reducing manual content
GitHub
creation time by ~40%.
Designed and implemented robust backend logic for data processing, user
LinkedIn management, and business workflows.
Collaborated closely with frontend developers, product managers, and QA

Technical Skills
engineers in an Agile environment.
Focused on performance optimization, reliability, and scalability of backend
services.
Backend Participated in architectural decisions and contributed to the overall technical
direction of the platform.
Java core
Spring Boot LoanBud - fintech platform modernizing access to U.S. SBA lending for small
businesses.
Spring Data JPA Developed and maintained Java/Spring Boot REST APIs for loan applications,
borrower portals, and internal workflows.
Spring Data JDBC Improved platform stability and performance by fixing production issues and
Spring Security optimizing search, filtering, and sorting for large datasets.
Implemented configuration-driven backend workflows to dynamically control
MapStruct borrower portal content and task assignment.
RESTful API Built backend functionality for PDF template processing and AcroForm field
mapping, enabling automated document generation and signing.
Maven Integrated external services and internal APIs, ensuring secure, permission-

Web Socket based access to lender-scoped data.
Collaborated with cross-functional teams (FE, QA, Product) on feature delivery,
JUnit testing debugging, and technical decisions.

Hibernate
Retrofit
Feign Client Projects
OpenAPI Specification
Liquibase March 2024 - May 2025
Apache Kafka Cardify
A cross-platform application for generating AI-powered flashcards from diverse
media sources (PDF books, YouTube videos, and images) using NLP and OCR
Databases technologies.

MySQL Designed a modular RESTful API using Spring Boot, following the MVC pattern and
layered architecture principles.
SQL Server Implemented secure JWT-based authentication.
AI Integration: Integrated OpenAI API (GPT-4o mini) for natural language
PostgreSQL processing and content generation in structured JSON format.
Used Google Cloud Vision OCR for extracting text from image-based inputs, such
as scanned book pages.
Language Developed endpoints for handling and parsing various file formats, including
PDFs and images.
Implemented subtitle extraction from YouTube videos.
Ukrainian - Native GitHub: https://github.com/KZMRK/cardify-server

English - Upper-Intermediate
 May 2023 - Jun 2023
Assignment Submission App
Web-oriented system for reviewing student projects. Within this system, students
can create assignments and link to a code repository for review. Reviewers, for their
part, have the opportunity to view, review the code and send comments to the code
with comments and suggestions for its improvement.
Backend: Spring Boot, Spring Data JPA, Spring Security, Web Socket also use Maven,
Lombok
Frontend: React, React Bootstrap, HTML/CSS
Database: MySQL
GitHub: https://github.com/KZMRK/AssignmentSubmission

Education

Jul 2025 - Present
ENGin Program
Certificate of ENGin Program Completion

Feb 2024 - May 2024
Calaton Academy
Java Backend Course

2021 - 2025
Lviv Polytechnic National University
Bachelor's Degree in Computer Science
Diploma with Honours

Jul 2022 - Dec 2022
Programming School++
Computer Science Basics Alumnus