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# Java Developer

- **Company:** Yonderland
- **Location:** Belgium
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** Application Programming Interfaces (APIs), Artificial Intelligence, Amazon Web Services, Amazon Elastic Compute Cloud, Cloud Engineering, Code Review, Databases, Relational Databases, Database Design, DevOps, Distributed Systems, Hibernate (Java), IntelliJ IDEA, Spring Framework, Junit, PostgreSQL, Apache Maven, MongoDB, MySQL, NoSQL, Performance Tuning, Mockito, Systems Integration, Data Logging, Data Processing, Spring-mvc, Retrieval-Augmented Generation, Large Language Models, Prompt Engineering, Spring-boot, Technical Debt, AI Coding Agents, Backend, Containerization, Integration Tests, Cassandra, Build Tools, Bitbucket, Web Technologies, Front End Software Development, Asynchronous Programming, Model Inference, Software Version Control, Docker, Microservices
- **Published:** November 12, 2026
- **Apply:** https://asadventure-career.talent-soft.com/vacature/vacature-senior-java-developer_2545.aspx

## About the Role

* 5-7+ years of backend software development experience.
 * Deep expertise with Java frameworks such as Spring Boot, Spring MVC, Hibernate, and other relevant libraries.
 * Extensive experience with relational databases (e.g., PostgreSQL, MySQL) and NoSQL databases (e.g., MongoDB, Cassandra). Proficiency in database design, optimization, and management.
 * In-depth understanding of web technologies, HTTP and REST. Understanding of web security principles.
 * Proficiency with development environments (e.g., IntelliJ IDEA), build tools (e.g., Maven), and version control systems (e.g., Bitbucket).
 * Advanced knowledge in designing and maintaining APIs and microservices architecture. Knowledge of setting up asynchronous communication in AWS.
 * Proficiency with testing frameworks like JUnit, Mockito, and integration testing tools.
 * Familiarity with containerization (e.g., Docker) in a cloud native way (AWS EC2).
 * Proven experience in building scalable systems, performance tuning, and managing large-scale distributed systems.
 * Hands-on experience integrating LLM APIs and AI inference endpoints, including prompt design and RAG/vector database patterns.
 * Exceptional problem-solving abilities to diagnose complex issues and implement effective solutions.
 * Excellent communication skills to articulate technical concepts to non-technical stakeholders and collaborate with cross-functional teams.
 * Ability to mentor and coach junior and mid-level developers, fostering a collaborative and growth-oriented environment.
 * Strategic mindset to align technical decisions with business goals and long-term vision.

## Description

* Design and implement complex backend services, APIs, and integrations in line with our architecture standards, proposing and defending options for microservices and domain boundaries.
 * Lead and own key backend features and cross-team initiatives end-to-end, from design through production, ensuring operational readiness.
 * Set and uphold code-quality expectations, championing clean code, test coverage, and performance across the services we own.
 * Apply secure-by-design and privacy-by-design principles, and ensure logging, monitoring, and alerting are fit for production and compliance.
 * Drive refactoring, technical debt reduction, and incremental modernisation, and support incident diagnosis and root-cause follow-up.
 * Mentor mid-level and junior backend engineers through code reviews, pairing, and design discussions, acting as a technical role model.
 * Collaborate closely with frontend, QA, DevOps, data, and product teams, translating technical trade-offs into clear options for stakeholders.
 * Bring hands-on AI knowledge to the role: integrating LLM APIs and AI inference endpoints into backend services, applying responsible, GDPR-compliant data handling, and using AI coding assistants to boost delivery quality and velocity.