Java Full Stack Developer

Location: Vienna (1–2 days on-site per week during onboarding, then 2-4 day per month; otherwise fully remote) Start: ASAP | Duration: 12 months (extension possible) | Workload: 100% Language: English (must-have) + German (nice to have)

We are seeking an experienced Java Full Stack Developer with a strong focus on backend development to join our agile team. Your role will involve designing and developing APIs, implementing microservice-based architectures, integrating with databases, and contributing to frontend development using JavaScript/TypeScript with React or Angular. You will collaborate closely with cross-functional teams in an agile environment. Experience in the telecommunications sector is a strong plus. €350 - €400 a dayKey Responsibilities

Design, develop, and maintain backend services using Java, Spring, and Spring Boot Implement and integrate REST APIs for internal and external systems Conduct unit testing using JUnit to ensure code quality Manage builds and dependencies with Maven Work with PostgreSQL, ideally including JSONB Design and develop scalable, maintainable microservice architectures Collaborate closely with product owners, architects, developers, and DevOps teams Contribute to the continuous improvement of development processes and tools Ensure solutions meet performance, stability, and security standards Contribute to the frontend using JavaScript/TypeScript and React or Angular Work with technologies from the Apache ecosystem where applicable (e.g. for services, integration, or tooling) Required Skills & Experience Proven professional experience in backend development with Java (Java 21 preferred) Strong knowledge of Spring and Spring Boot Experience with REST API development and integration Proficiency in JUnit for unit testing Experience in Maven build management Solid knowledge of PostgreSQL (JSONB is a plus) Strong background in microservice architecture design and implementation Experience with frontend development using JavaScript/TypeScript and React or Angular Familiarity with Apache-based technologies in a typical Java backend stackAgile mindset and experience working in Scrum/Kanban teams Excellent command of English (spoken & written) Nice to Have****Kubernetes & Helm for deployment and orchestrationSOAP service integration experience Experience with Graylog for logging and monitoringTelecommunications industry knowledge (big plus) Knowledge of Kafka , Apache Why Join Us? Work on impactful, enterprise-grade solutions Agile, collaborative work environment with international teams Opportunity to influence architecture and technology decisions Engagement in a technically demanding, modern Java backend / Fullstack environment**Interested?**Please send your updated CV including availability and hourly rate expectations. We look forward to hearing from you! Please contact me by email at elena.kahraman@qualysoft.com, or via LinkedIn. Thank you for your understanding! +43 699 14402417 We may use artificial intelligence (AI) tools to support parts of the hiring process, such as reviewing applications, analyzing resumes, or assessing responses and identifying potential inconsistencies or verification signals in application materials based on available information. These tools assist our recruitment team but do not replace human judgment. Final hiring decisions are ultimately made by humans. If you would like more information about how your data is processed, please contact us.