{"id":839135,"url":"https://alion.io/job/upstream-senior-software-engineer-java","title":"Senior Software Engineer, Java","company":{"id":55560,"name":"Upstream","domain":"upstreamsystems.com","url":"https://alion.io/company/upstreamsystems","size_band":null,"is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"Workable","truth_index":{"grade":"B","score":84,"open_postings":8,"ghost_share":0,"stale_share":0.625,"repost_share":0,"time_to_fill_p50_days":null,"computed_at":"2026-10-06T05:45:30Z"}},"role":"Backend","role_family":"Backend","seniority":"senior","employment_type":"full_time","work_mode":"on_site","remote_scope":null,"remote_scope_basis":null,"remote_working_hours":null,"hiring_geo_confidence":"structured","locations":["Gerakas, Greece"],"countries":["GR"],"hiring_countries":[],"hiring_countries_total":0,"salary":null,"salary_estimate":{"min_usd":42000,"max_usd":116000,"period":"year","method":"global_role_cell_scaled_by_country","sample_n":5573},"experience_years_min":null,"visa_sponsorship":false,"relocation_package":false,"has_equity":false,"technologies":[{"name":"Agile","optional":false},{"name":"Apache Kafka","optional":false},{"name":"CI/CD","optional":false},{"name":"Couchbase","optional":false},{"name":"ElasticSearch","optional":false},{"name":"Git","optional":false},{"name":"Hazelcast","optional":false},{"name":"Hibernate","optional":false},{"name":"Java","optional":false},{"name":"Maven","optional":false},{"name":"RabbitMQ","optional":false},{"name":"Redis","optional":false},{"name":"Spring Framework","optional":false},{"name":"SQL","optional":false}],"status":"live","first_seen_at":"2025-12-08T00:00:00Z","employer_posted_date":"2025-12-08","last_verified_at":"2026-10-06T20:51:57Z","board_verified":true,"closed_at":null,"days_open":302,"trust":{"level":"stale","repost_count":0,"flags":["stale"],"days_open":302},"description":"Who we are\nUpstream is a global leader in mobile marketing automation and digital service innovation, enabling Mobile Network Operators (MNOs) and brands to grow revenue, improve customer engagement and succeed in the digital economy. With over two decades of experience and operations spanning 45+ markets across Africa, Latin America, Asia, Europe, and the Middle East, we are a trusted partner to more than 60 MNOs worldwide.\nHeadquartered in Athens, Greece, and with regional hubs in London, Dubai, Johannesburg, Lagos, São Paulo and Rio de Janeiro, Upstream combines global expertise with deep local insight. Our end-to-end approach encompasses strategy, creative development, technical deployment, campaign execution, and ongoing optimization, ensuring seamless, scalable, and performance-driven service delivery.\nThe role\nWe are looking for an enthusiastic Senior Software Engineer to join our Software Development team in Athens, Greece.\nAs a Senior Software Engineer, you will be part of a very competent team that works on mission - critical applications contributing in all phases of the development process. You will be responsible for Java application development, supporting business objectives while providing expertise in full software development lifecycle, from concept and design, to testing.\nYour main responsibilities will be:\nWrite well designed, testable, efficient software modules.\nEnsure designs are in compliance with specifications and that specifications cover all needed aspects of the implementation.\nPrepare and produce releases of software components.\nProvide support for production systems.\nCreate/ review design documentation and provide feedback on test plans.\nSupport continuous improvement by investigating alternatives and technologies and presenting these for architectural review.\nSupport and coach junior developers.\nRequirements\nBSc/MSc in Computer Science, Software Engineering or equivalent.\n 5+ years of full time professional experience in designing and developing applications using the Java ecosystem.\nSolid background in Object Oriented Analysis and Design.\nExperience with popular Java frameworks and technologies such as Spring Framework, JPA/Hibernate.\nExperience with asynchronous messaging technologies (e.g. RabbitMQ, Kafka).\nExperience designing and developing HTTP web services.\nExcellent knowledge of SQL and RDBMS concepts.\nWorking knowledge of Maven, Git and Continuous Delivery principles.\nExperience in the following will be extra appreciated:\nNoSQL databases such as Redis, Elasticsearch, Couchbase.\nCaching technologies, such as Hazelcast, EhCache.\nHorizontally scalable, distributed, microservices architectures.\nYou will be an excellent fit for our team if you are:\nStrong team player with good communication skills.\nEager to work with leading-edge technologies.\nReliable and dedicated professional with clear thinking and strong attention to detail.\nAble to work well under pressure and meeting deadlines in sometimes challenging situations.\nAble to multitask and thrive in a dynamic environment as well as balance and prioritize activities to ensure critical items are addressed.\nBenefits\nWe offer a competitive base salary and benefits, directly dependent on the candidate’s qualifications and skills. The real excitement comes from working closely with a dynamic, smart, agile, and highly motivated team in a competitive and fast-paced environment.\nFollow us on LinkedIn and stay updated on our latest news. Upstream is an equal-opportunity employer.\nUpstream is an equal-opportunity employer. The Company does not discriminate on the basis of race, color, creed, pregnancy, religion, gender, national origin, age, disability, marital status, or any other legally protected status. The Company also makes reasonable accommodations for disabled employees. Finally, the Company prohibits the harassment of any individual based on their protected status. 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