Serhii Korol - Senior Software Engineer

Q: Where is Serhii based?

Serhii is based in Thessaloniki, Greece and can operate in on-site , hybrid , and remote work models.

Q: What languages does Serhii speak?

Serhii speaks the following languages: Greek (Advanced), English (Intermediate), German (Elementary) .

Q: How many years of experience does Serhii have?

Serhii has at least 8 years of experience. During this time, Serhii has worked in at least 4 different roles and for 4 different companies . The average length of individual experience is 2 years . Note that Serhii may not have shared all experience and actually has more experience.

Q: What is Serhii's latest experience?

Serhii's most recent position is Senior Software Engineer at Kilwar LLC .

Q: What companies has Serhii worked for in recent years?

In recent years, Serhii has worked for Kilwar LLC and Eatcheap Agency .

Q: Which industries is Serhii most experienced in?

Serhii is most experienced in industries like Banking and Finance and Information Technology .

Q: Which business areas is Serhii most experienced in?

Serhii is most experienced in business areas like Information Technology , Product Development , and Business Intelligence . Serhii also has some experience in Project Management and Operations .

Q: Which industries has Serhii worked in recently?

Serhii has recently worked in industries like Banking and Finance .

Q: Which business areas has Serhii worked in recently?

Serhii has recently worked in business areas like Information Technology , Business Intelligence , and Project Management .

Recommended expert

Thessaloniki, Greece

Experience

Sep 2021 - Oct 2024

3 years 2 months

United States

Senior Software Engineer

Kilwar LLC

Developed and maintained high-performance Java-based financial applications, ensuring compliance with security and availability requirements.
Led the Findur integration and optimization project, reducing processing time by 30% and enhancing system scalability.
Designed and implemented CI/CD pipelines with Jenkins and GitHub Actions, reducing deployment time by 40%.
Conducted performance testing and database optimizations to improve transaction efficiency and data retrieval.
Collaborated with cross-functional teams in an Agile environment, implementing DevOps best practices.

Jul 2020 - Aug 2022

2 years 2 months

United States

Backend Developer

Eatcheap Agency

Built and optimized enterprise banking applications using Java, Spring Boot, and Oracle RDBMS.
Developed highly available and scalable services, ensuring system uptime of 99.99%.
Led a data warehouse migration project, improving data retrieval speeds by 45%.
Automated performance monitoring and error handling using Ansible and Terraform.
Enhanced security measures, implementing OAuth, JWT, and API security protocols.

Mar 2018 - Mar 2020

2 years 1 month

Germany

Software Engineer

NERDZZ Digitalagentur GmbH

Spearheaded the migration of legacy services to containerized microservices in AWS (EKS, Lambda, API Gateway).
Developed high-performance distributed event-driven systems with Kafka and RabbitMQ, improving message throughput by 20%.
Integrated Cloud Native Application Protection Platforms (CNAPP) for Kubernetes security, enhancing system resilience.
Built self-healing and autoscaling Kubernetes clusters, reducing operational downtime.
Led architectural discussions and mentored engineers, driving innovation in the API and cloud computing space.

Jun 2016 - Mar 2018

1 year 10 months

Greece

Software Engineer (Intern)

NUS Solutions Inc

Developed and maintained scalable web applications using React.js, Next.js, and TypeScript, ensuring high performance and seamless user experience.
Designed and implemented RESTful APIs and GraphQL endpoints to optimize data fetching and improve application efficiency.
Integrated Redux for state management, enhancing application responsiveness and reducing load times.
Spearheaded UI/UX improvements by implementing Tailwind CSS, Material UI, and custom component libraries, leading to a 30% increase in user engagement.
Optimized frontend performance by implementing lazy loading, code splitting, and caching strategies.
Collaborated closely with backend developers to integrate APIs, debug issues, and ensure smooth communication between frontend and backend.
Led the migration of a legacy application to modern web technologies, improving maintainability and scalability.
Implemented CI/CD pipelines (GitHub Actions, GitLab CI) to automate deployments and testing, reducing manual effort by 15%.
Worked in an Agile/Scrum environment, participating in sprint planning, daily stand-ups, and code reviews.

Industry Experience

See where this freelancer has spent most of their professional time.

Experienced in Banking and Finance and Information Technology.

Banking and Finance

Information Technology

Business Area Experience

See which departments and functions this freelancer has contributed to most.

Experienced in Information Technology, Product Development, Business Intelligence, Project Management, and Operations.

Information Technology

Product Development

Business Intelligence

Project Management

Operations

Summary

With over 8 years of experience in backend and full-stack development, I specialize in designing, developing, and optimizing high-performance Java applications. My expertise spans financial technology platforms, RDBMS databases, and DevOps practices, enabling the development of scalable, secure, and resilient software solutions. I have a strong background in Java, Spring, SQL, and cloud-based architectures, with hands-on experience in Findur, Endur, and performance testing. A dedicated team player, I excel in Agile environments, contributing to test-driven development (TDD) and promoting continuous integration and deployment (CI/CD) methodologies.

Skills

Architecture
Integration Strategy
0 - 1 Product Development
Api Design And Development
Ui/ux Design And Development
Software Development
Global/local People Management (Onshore/offshore)
Product/project Collaboration
Process Structuration And Optimization
Executive Leadership
Continuous Improvements
Professional Devops Services
Backend Development: Java, Spring, Spring Boot, Hibernate, Rest Apis
Databases: Oracle Rdbms, Postgresql, Mysql, Sql, Data Warehousing
Devops & Ci/cd: Jenkins, Github Actions, Docker, Kubernetes, Terraform
Cloud Technologies: Aws (Ec2, Rds, Lambda, S3), Azure
Financial Technology: Findur, Endur, Financial Applications, Performance Testing
Software Development Practices: Agile, Scrum, Test-driven Development (Tdd), Clean Code
Version Control & Automation: Git, Gitlab, Bitbucket, Ansible, Ci/cd Pipelines

Languages

Greek

Advanced

English

Intermediate

German

Elementary

Education

Apr 2010 - Sep 2014

University of Peloponnese

Bachelor’s degree · Computer Science and Mathematics · Greece

Certifications & licenses

Agile Development Certification

Institution of Peloponnese

Statistics

Experience

Total positions 4

Experience in Banking and Finance 4.5 y

Avg length 2 y 3 m

Longest experience 3 y 1 m

Global Experience

Countries worked in 3 (United States, Germany, Greece)

Primary country United States

Expertise

Recent roles Senior Software Engineer, Backend Developer, Software Engineer

Main industries Banking and Finance, Information Technology

Main business areas Information Technology, Product Development, Business Intelligence

Qualifications

Highest degree Bachelor

Certifications earned 1

Profile

Created

November 2025

Last Update

November 2025

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Frequently asked questions

Do you have questions? Here you can find further information.

Where is Serhii based?

Serhii is based in Thessaloniki, Greece and can operate in on-site, hybrid, and remote work models.

What languages does Serhii speak?

Serhii speaks the following languages: Greek (Advanced), English (Intermediate), German (Elementary).

How many years of experience does Serhii have?

Serhii has at least 8 years of experience. During this time, Serhii has worked in at least 4 different roles and for 4 different companies. The average length of individual experience is 2 years. Note that Serhii may not have shared all experience and actually has more experience.

What roles would Serhii be best suited for?

Based on recent experience, Serhii would be well-suited for roles such as: Senior Software Engineer, Backend Developer, Software Engineer.

What is Serhii's latest experience?

Serhii's most recent position is Senior Software Engineer at Kilwar LLC.

What companies has Serhii worked for in recent years?

In recent years, Serhii has worked for Kilwar LLC and Eatcheap Agency.

Which industries is Serhii most experienced in?

Serhii is most experienced in industries like Banking and Finance and Information Technology.

Which business areas is Serhii most experienced in?

Serhii is most experienced in business areas like Information Technology, Product Development, and Business Intelligence. Serhii also has some experience in Project Management and Operations.

Which industries has Serhii worked in recently?

Serhii has recently worked in industries like Banking and Finance.

Which business areas has Serhii worked in recently?

Serhii has recently worked in business areas like Information Technology, Business Intelligence, and Project Management.

What is Serhii's education?

Serhii holds a Bachelor in Computer Science and Mathematics from University of Peloponnese.

Does Serhii have any certificates?

Serhii has 1 certificate: Agile Development Certification.

What is the availability of Serhii?

Serhii is immediately available part-time for suitable projects.

What is the rate of Serhii?

Serhii's rate depends on the specific project requirements. Please use the Meet button on the profile to schedule a meeting and discuss the details.