Senior Java Software Engineer

About the role

Upstream is seeking a Senior Software Engineer to join its Athens development team. You will work on mission‑critical Java applications, contributing across the full software development lifecycle from concept and design to testing and production support.

Key responsibilities

• Write well‑designed, testable, and efficient Java software modules.
• Ensure designs comply with specifications and cover all implementation aspects.
• Prepare and produce releases of software components.
• Provide support for production systems and troubleshoot issues.
• Create and review design documentation and give feedback on test plans.
• Investigate alternative technologies and present findings for architectural review.
• Support and coach junior developers.

Required profile

• BSc/MSc in Computer Science, Software Engineering or equivalent.
• 5+ years of professional experience designing and developing Java applications.
• Strong background in object‑oriented analysis and design.
• Excellent communication, teamwork, and attention to detail.
• Ability to work under pressure, meet deadlines and multitask.

Required skills

• Java
• Spring Framework
• JPA / Hibernate
• RabbitMQ or Kafka
• HTTP web services
• SQL and relational databases
• Maven, Git and Continuous Delivery principles
• Redis, Elasticsearch, Couchbase (optional)
• Hazelcast, EhCache (optional)
• Microservices and distributed architectures