G+D makes the lives of billions of people around the world more secure. We create trust in the digital age with integrated security technologies in three business areas: Digital Security, Financial Platforms and Currency Technology. We have been a reliable partner for our customers for over 170 years with our innovative solutions for SecurityTech!

At Payment Technology, our mission is to be at the start of every transaction and to make it secure and simple. We also create contemporary payment and banking solutions for our digital age. As a one-stop shop, we produce and personalise hundreds of millions of payment cards every year and store their "digital twins" - mobile and digital. Would you like to actively shape the digital transformation with us?

About the Project Join a team working on one of

G+D's strategic projects in digital payments: the Digital Euro .

G+D has been selected by the

European Central Bank (ECB) as the first-ranked provider for the Digital Euro offline solution , contributing to the development of a key component of the future digital euro infrastructure.

Within this project, you will work on a specialized

Trusted Service Manager (TSM) platform , helping ensure that its backend services are

secure, reliable and thoroughly tested .

The core architecture and initial product are already in place. The team is now focused on expanding the platform with new features and building robust automation around it.

Summary We are looking for a

Senior Java Backend Developer

to lead the design, development, and maintenance of secure, scalable, cloud-native microservices for our Trusted Service Manager (TSM) platform. This role focuses on backend development with Spring Boot 4, cryptographic operations, automation, and test-driven practices in a Kubernetes-based environment.

Key Responsibilities

Lead the end-to-end development and implementation of TSM backend services and microservices.

Design, develop, and optimize robust Java backend applications using:

Spring Boot 4 (including Spring Boot Actuator)

Spring Cloud

Spring Data

Implement and maintain API-first architectures (REST, OpenAPI),



ensuring clear contracts and maintainable integrations.

Build, deploy, and operate cloud-native applications using:

Docker containers

CI/CD pipelines and automation tooling

Implement secure cryptographic operations, including:

PKI-based workflows

Encryption, signing, and key management best practices

Design data models and access layers using MongoDB for scalable, high-performance storage.

Drive automated testing and quality assurance:

TDD and BDD

Unit, integration, and end-to-end test automation

Security testing (SAST, DAST)

Apply and advocate agile methodologies (Scrum), engineering best practices, and secure coding standards.

Collaborate closely with architects, product owners, QA engineers, and other developers to deliver high-quality solutions.

Guide and mentor other team members, promoting knowledge sharing and continuous improvement.

Contribute to observability and operations using Spring Boot Actuator and monitoring/logging tools.

Required Skills & Experience

University degree in Computer Science, Software Engineering, or a related field.

Extensive experience as a senior backend Java developer.

Strong, hands-on expertise with:

Spring Boot (v4), including Spring Boot Actuator

Spring Cloud and Spring Data

Professional experience designing and implementing microservices in cloud-native environments.

Proficiency in MongoDB, including schema design, performance tuning, and operational considerations.

Solid knowledge of Docker and Kubernetes for containerized deployments and orchestration.

Proven track record building API-first solutions:

OpenAPI/Swagger specifications

Deep understanding of cryptography concepts and tooling:

PKI, X.509 certificates





Secure key management and cryptographic protocols

Experience in agile teams (Scrum) with:

TDD and BDD

Automated testing strategies

Security testing (SAST, DAST)

Familiarity with large-scale, high-availability, enterprise-grade systems.

Hands-on experience with Atlassian and DevOps tooling:

Jira, Confluence

Git (GitLab/GitHub)

SonarQube, Jenkins, Nexus, Maven

Strong problem-solving skills, with the ability to troubleshoot complex distributed systems.

Excellent communication skills and a collaborative, team-oriented mindset.

Fluent English (spoken and written).

Nice to Have

Experience developing SDKs (Java or other languages) for external integration.

Knowledge of client application development (e.g., mobile or desktop clients interacting with backend APIs).

Background in financial services, payment systems, or digital currency projects.

This role is ideal for a senior backend engineer who enjoys working on secure, high-availability microservices, is comfortable with advanced cryptography, and wants to drive automation and quality across the entire delivery lifecycle.

What We Offer

Culture and Diversity: Join a people oriented environment with different nationalities and a great team spirit, flat hierarchies (everyone speaks to everyone). Equal Opportunity Employer and LGBT+ friendly.

Innovative Products: Design and develop business processes and IT solutions for innovative products and digital solutions.

Career Development: Continuous training and coaching, talent program.

Social Benefits: versátil compensation (transport tickets, childcare vouchers, training, private insurance) and in-house parking.

Flexible work time and remote work: M-Th 8.30 - 17.30 and Fri 8.30 - 15.30, hybrid model.

Own Canteen: Take a break with our breakfast and lunch service: Choose between a big range of menus, salad desk and sandwich service. Fruit packages.

Location: El Prat de Llobregat. Easy communication by public transport (Bus 88 and 110, Metro L10 Riu Vell from Barcelona, PR4 from El Prat) o private transport.

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📌 Senior Java Backend Developer (El Prat de Llobregat)
🏢 Giesecke+Devrient
📍 El Prat de Llobregat