Back-end Developer

**COSMOTE Global Solutions NV , a distinguished member of the OTE Group of Companies, is an ICT Systems Integrator offering a comprehensive range of ICT Solutions and Services. We are actively seeking a seasoned ** Back-end Developer to strengthen our innovative technology team.

In this role, you will be responsible for developing and maintaining robust server-side applications, ensuring seamless integration with front-end components, and optimizing system performance. You will collaborate with cross-functional teams to deliver scalable, secure, and efficient back-end solutions that meet business requirements.

Key Responsibilities:

• Develop and maintain scalable back-end services and APIs.
• Implement core business logic and ensure data integrity and security.
• Integrate server-side logic with front-end components.
• Design and optimize databases for performance and reliability.
• Adopt secure coding practices to protect application and data security.
• Follow best practices for code quality, versioning, and documentation.
• Conduct code reviews, debugging, and testing to identify and resolve issues.
• Collaborate with product managers, front-end developers, and other stakeholders during the development lifecycle.
• Participate in architectural decisions and technology evaluations to improve system design.
• Maintain up-to-date technical documentation.

Requirements

• Bachelor’s Degree in Computer Science, Engineering, or a related field.
• Minimum of 10 years of professional experience in back-end development.
• Strong proficiency in Java (version 17 or above), Kotlin, vert.x, Spring Boot (WebFlux), and Hibernate.
• Experience with microservices architecture and API-driven development.
• Knowledge of integration protocols such as AS4.
• Proficient in database design and management using MongoDB, PostgreSQL, Virtuoso Triple Store, and OpenSearch.
• Hands-on experience with containerization and orchestration tools such as Docker and Kubernetes.
• Solid understanding of security frameworks including OpenID Connect, OAuth2, TLS, and Keycloak.
• Experience with security testing and dependency management tools such as SAST, DAST, Fortify, SonarQube, Sonatype, Dependency-Track, and Maven.
• Proficient with collaboration and productivity tools including JIRA, Confluence, Office 365, and SharePoint.
• Excellent problem-solving skills, with the ability to work effectively in a multicultural and international environment.
• Fluent in English (C2 level) both spoken and written.
• Strong communication skills, adaptability, and capacity to work under changing requirements.