Senior Java Backend Engineer– Identity & Security
Summary
Senior Java Backend Engineer building Germany's next-generation Identity Provider platform for the national healthcare Telematics Infrastructure, owning domain-driven modules end to end. Core stack: Java 25, Spring Boot 4.1, OAuth 2.0/OIDC, PostgreSQL, Kafka, Docker/Kubernetes.
Company Description
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.
Job Description
We are looking for a highly skilled Senior Java Backend Engineer to join a team building Germany's next-generation Identity Provider platform for the national healthcare Telematics Infrastructure (TI), enabling millions of statutory health insurance members to securely access digital healthcare services.
This is a security-critical, gematik-regulated platform built on Java 25 and Spring Boot 4.1, delivering production-grade OAuth 2.0/OIDC identity services, hardware-backed cryptography, PII protection, and audit-grade quality.
Our backend is designed as a domain-driven modular monolith (Modulith) that continuously evolves toward a clean hexagonal architecture. As a Senior Java Backend Engineer, you will own bounded-context modules end-to-end—from domain design and implementation to testing, operations, and architectural evolution—helping shape one of Germany's most advanced digital identity platforms.
Technology Stack
Backend Development
- Java 25
- Spring Boot 4.1
- REST APIs
- Spring Security
Identity & Security
- OAuth 2.0
- OpenID Connect (OIDC)
- HSM-backed Key Management
- Data Encryption
- Security Compliance
Database & Messaging
- PostgreSQL
- Flyway
- Apache Kafka
- Avro
- Schema Registry
Testing & Quality
- JUnit 5
- Testcontainers
- Code Reviews
- CI/CD
Observability
- OpenTelemetry
- Micrometer
- Structured Logging
- Metrics & Tracing
Architecture & DevOps
- Modular Monolith (Modulith)
- Hexagonal Architecture
- Domain-Driven Design (DDD)
- Docker
- Kubernetes
- Git
What We Offer
- Opportunity to contribute to one of Germany’s most advanced digital identity platforms.
- Work in a highly modern environment using Java 25 and Spring Boot 4.1.
- Exposure to cutting-edge technologies in identity management, security, and healthcare platforms.
- Strong engineering culture with emphasis on architecture, code quality, and technical excellence.
- Collaboration with highly experienced architects, security specialists, and platform engineers.
- Professional growth opportunities in software architecture, cybersecurity, and identity solutions.
- International and multicultural working environment.
* Please be informed that our remote working possibility is only available within Hungary due to European taxation regulation.
- 5+ years of professional experience in backend software engineering.
- Strong expertise in:
- Java
- Spring Boot
- REST API development
- PostgreSQL
- Experience implementing OAuth 2.0, OpenID Connect (OIDC), or similar authentication and authorization solutions.
- Experience designing and developing modular, maintainable backend systems.
- Understanding of modern software architecture principles and architectural evolution toward decoupled systems.
- Experience with:
- JUnit
- CI/CD pipelines
- Git-based development workflows
- Experience working in regulated, security-critical, or compliance-driven environments.
- Fluent English, both written and spoken.
Advatanges:
- Experience with:
- Apache Kafka
- Avro
- Schema Registry
- Flyway
- Testcontainers
- Knowledge of:
- Spring Security
- OpenAPI / Swagger
- Micrometer
- OpenTelemetry
- Docker and Kubernetes experience.
- Experience with:
- Hardware Security Modules (HSM)
- Applied Cryptography
- Secure Software Development Practices
- Familiarity with:
- Hexagonal Architecture
- Domain-Driven Design (DDD)
- ArchUnit
- Experience in digital identity, healthcare, or public-sector platforms.
- German language skills are considered a strong advantage.