Job Description

Life at Ness

At Ness, people come first. Here, you'll be part of a vibrant team that values curiosity, innovation, and growth. We work with industry-leading clients on projects that truly make an impact while supporting every team member in carving out their unique career path. With resources for learning, certifications, and hands-on experiences, Ness offers you more than just a job—it’s a place where your ideas, ambition, and well-being matter.

The Role

We are looking for an experienced Java Developer to join a project focused on integrating third-party systems for large-scale data collection and processing.

The platform is built on an event-driven architecture, designed to handle high data volumes in real time with strong guarantees around scalability, reliability, and performance. You will join a small, senior-level team with a high degree of technical ownership, autonomy, and direct influence on architectural and technical decisions.

While the role is strongly focused on backend development, we value engineers who are open to contributing beyond their core area when needed—whether that’s supporting DevOps or collaborating on cross-cutting initiatives. Familiarity with AI technologies is a strong plus, as we continue integrating intelligent capabilities into our products and workflows.

This role is well-suited for someone who enjoys working in complex systems, taking end-to-end responsibility, and continuously improving both the product and the way it is built.

Salary: from 2.300 EUR/month, depending on skills and experience + benefits. The final offer for the selected candidate will reflect the candidate´s comprehensive assessment, skills, and past work experience.

Location: Slovakia only

What you'll do:

• Design, implement, and maintain Java-based backend services, components, and integrations
• Collaborate across a distributed Agile organization (Scrum or Kanban) to deliver outcomes
• Take ownership of high-complexity technical tasks, from design through production
• Actively support quality assurance, including test automation, integration testing, and code reviews
• Contribute to and evolve architecture, development standards, and best practices
• Participate in architectural discussions and technical decision-making
• Continuously propose and drive improvements in system design, performance, and developer experience

What you'll bring:

Experience & Professional Profile

• Experience designing high-availability, scalable, and high-performance backend systems
• Hands-on background in high-volume data processing and distributed systems
• Solid understanding and practical use of Agile methodologies
• Experience applying Test-Driven Development (TDD) and modern QA practices
• Familiarity with CI/CD principles, pipelines, and automated delivery
• Proven ability to work effectively in a corporate, cross-functional environment
• Self-driven, resilient, and comfortable operating in complex and evolving systems
• Team-oriented mindset with the ability to influence and motivate others
• Very good command of spoken and written English

Key skillsets:

• Java 11–21 with knowledge of the JVM and language fundamentals
• Spring ecosystem: Spring Boot, Spring Web / Web Flux (nice to have), Spring Data
• Build tools: Maven and/or Gradle
• Hands-on experience with event-driven architectures
• Experience with Azure (preferable), alternatively Amazon Web Services
• Infrastructure as a code: Terraform, Ansible
• Docker and Kubernetes
• Experience with Apache Kafka (or similar message brokers)
• Strong understanding of REST APIs (gRPC is a plus)
• Experience with relational and NoSQL databases (e.g., PostgreSQL, MySQL, MongoDB (Cosmos))

Nice to have:

• Experience with Akka (Classic or Typed) is a strong plus
• Familiarity with reactive programming (e.g., Project Reactor, Akka Streams)
• Exposure to event-driven architectures, including event sourcing
• Hands-on experience with CI/CD pipelines (GitHub Actions, GitLab CI, or Azure DevOps)
• Working knowledge of security concepts such as OAuth2, JWT, and Basic Authentication

While many of our roles involve just 2–3 steps, some client processes may include additional conversations. Regardless of the path, we aim to keep every step transparent and respectful of your time.

Ready to Start Your Journey?