Senior Back End (Java) Engineer

About the Position

Senior Back End (Java) Engineer

At Avenga, we believe that human creativity empowers technology that matters. Operating globally, our 6000+ specialists provide a full spectrum of services, including business and tech advisory, enterprise solutions, CX, UX and UI design, managed services, product development, and software development.

You will build and stabilize the backend systems that power our product integrations. You’ll work on secure, high-load Java services, design reliable APIs, and contribute to system resilience during critical delivery and stabilization phases. This role is ideal for a senior engineer who values clean architecture, operational reliability, and building backend solutions that scale in real-world environments.

Responsibilities

• Implement ICS backend components according to the defined system architecture
• Design and develop REST APIs and server-side integration logic
• Write stable, testable, and audit-ready code
• Participate in UAT support and system stabilization phases
• Analyze logs, errors, and retry scenarios to ensure system reliability

Requirements

• Strong Java expertise (17+), experience with Java 21 is a plus
• Spring Boot 3.x (REST controllers, exception handling, configuration)
• API development & integration: REST (OpenAPI/Swagger) and SOAP
• Data processing & integrations: XML parsing, XSD validation, large payload handling
• Idempotent and reliable backend processing
• Security awareness: mTLS fundamentals, secure handling of sensitive data, no PII logging
• Database experience: MS SQL
• Code quality & testing: clean code, unit and integration tests
• Operational mindset: logs, error handling, retries, system stabilization experience

Nice to Have

• Experience working on enterprise or integration-heavy systems
• Familiarity with regulated or audit-sensitive environments

We Offer

At Avenga, everyone matters. We provide equal opportunities in recruitment, career development, and leadership, regardless of race, ethnicity, gender identity, sexual orientation, disability, age, religion, or any other characteristic. We are committed to fostering a work environment where our diverse community of employees, candidates, and business partners actively shapes our growth. By bringing together people from different backgrounds and experiences, we build a workplace where everyone feels free to be themselves while honoring the boundaries of others.

About the Company

Avenga is a global company with a presence in multiple locations, including Banja Luka (BA), Beograd (RS), and Bitola (MK). We offer a hybrid work location model, allowing flexibility and collaboration.

Application Process

1. Application: Send us your application, we are ready to hear your story and explore how we can grow together.
2. Review: Our team carefully reviews every application with curiosity and care.
3. Talent Acquisition Interview: Meet our Talent team to talk about your goals and learn more about who we are, what we offer, and how we support our people.
4. Technical Interview: Dive deeper into your expertise and understand your strengths, problem-solving skills, and thought process.
5. Customer Interview: For some roles, especially when our clients are closely involved, you might also have a conversation with them.
6. Job Offer: If we both feel it’s the right match, we will send you an offer to join us.
7. Welcome: Your new team is excited to meet you, support you, and build something great together.