Full-Stack Developer (REF4999W)

As Hungary’s most attractive employer in 2025 (according to Randstad’s representative survey), Deutsche Telekom IT Solutions is a subsidiary of the Deutsche Telekom Group. The company provides a wide portfolio of IT and telecommunications services with more than 5300 employees. We have hundreds of large customers, corporations in Germany and in other European countries. DT-ITS recieved the Best in Educational Cooperation award from HIPA in 2019, acknowledged as the the Most Ethical Multinational Company in 2019. The company continuously develops its four sites in Budapest, Debrecen, Pécs and Szeged and is looking for skilled IT professionals to join its team. The Telekom Distribution Partner Portal (T‑VPP) is the central entry point for both internal and external sales of Deutsche Telekom products. Our distribution partners use T‑VPP to market fixed-line and mobile products via a unified web interface and B2B web service integrations. We are looking for a Senior Developer with strong backend expertise to strengthen our team. More than 80% of the daily work is focused on backend development (enterprise services, integrations, security, data processing), while around 20% involves frontend tasks. Your Main Focus Backend development with Spring-based enterprise applications (80%) Integration with internal and external systems via REST and SOAP Secure API design and implementation Production support, monitoring, and performance optimization Occasional frontend work (JSF/React/Angular) (~20%) Core Technical Requirements (Most Important) Deep knowledge of Spring Core (IoC, bean lifecycle, AOP, scopes) Strong experience with Spring Security (authentication, authorization, OAuth2, SAML, session handling) Solid expertise with Spring Data (JPA) and relational databases Extensive experience designing and implementing REST and SOAP services Strong Java knowledge (Java 11+) and enterprise application design System Design & Architecture Strong system design skills Knowledge of core design patterns and architectural principles Experience designing scalable, secure enterprise systems Ability to analyze trade-offs and propose sustainable technical solutions Production & Operations Experience Real production experience maintaining enterprise applications Ability to investigate complex production issues Experience with monitoring and metrics tools (e.g., ELK, Grafana) Understanding of performance tuning and troubleshooting under load DevOps & Infrastructure Hands-on experience with Docker Experience deploying applications to Kubernetes Familiarity with GitLab CI/CD pipelines Understanding of deployment strategies and environment configuration Security Awareness Strong understanding of secure coding practices Awareness of OWASP recommendations (e.g., OWASP Top 10) Experience implementing secure authentication and authorization flows Understanding of common web vulnerabilities and mitigation strategies Nice to Have Experience with AWS Cloud Messaging systems (Kafka, JMS) Experience with enterprise integration patterns Frontend frameworks (React, Angular) Soft Skills Strong communication skills Ability to challenge and refine requirements Fluent technical English Ownership mindset and proactive approach This position is ideal for a senior engineer who enjoys working on complex enterprise systems, values clean architecture, and is confident operating in production environments. * Please be informed that our remote working possibility is only available within Hungary due to European taxation regulation.