Senior Java Developer - API SDK Team @ING Hubs Romania

Discover ING Hubs Romania

ING Hubs Romania offers 130 services in software development, data management, non-financial risk & compliance, audit, and retail operations to 24 ING units worldwide, with the help of over 2000 high-performing engineers, risk, and operations professionals.

We started out in 2015 as ING’s software development hub, then steadily expanded our range to include more services and competencies. Now we provide borderless services with bank-wide capabilities and operate from two locations: Bucharest and Cluj-Napoca.

Our tech capabilities remain the core of our business, with more than 1800 colleagues active in Data and Analytics Tech, Tech Foundation and Channels, Retail Core Banking and Architecture, and Global Products and Technology Services.

We enjoy a flexible way of working and a highly collaborative environment, where fair and constructive feedback is encouraged.

For us, impact isn't a perk. It's the driver of our work. We are guided and rewarded by a shared desire to make the world a better place, one innovative solution at a time. Our colleagues make it their job to do impactful things and they love doing it in good company. Do you?

The Mission

The API SDK is ING's core framework for developing secure, resilient, and high-performance APIs. This role offers the opportunity to work on foundational platforms that power ING's digital banking capabilities across our global technology ecosystem.

API SDK is a Spring Boot-based framework that serves as the foundation for developing APIs. It's a lightweight layer on top of Spring Boot that configures beans and filters specific to the ING landscape, including:

• Service registry integration for automatic service registration and discovery
• Pre-configured resilient HTTP client for inter-service communication
• Security components (token validation, access control, and authorization)
• Centralized logging and metrics integration with monitoring platforms
• Service mesh connectivity and proxy support for polyglot architectures

Your day to day

Even if you start your day from the comfort of your home or drink your morning coffee in our office garden, your day will be quite similar when comes to tasks. Here are your daily responsibilities:

Framework Development

• Develop and maintain the API SDK and core Toolkit components.
• Deliver new capabilities focused on security, resilience, and observability.
• Evolve the framework while ensuring backward compatibility.

Platform Integration

• Integrate the framework with container platforms, messaging systems, API gateways, and service mesh solutions.
• Build and maintain connectivity modules for different deployment models.

Developer Experience

• Design intuitive APIs and configuration interfaces.
• Create documentation, testing tools, and reference implementations to support adoption and best practices.

Community & Support

• Support development teams using the SDK.
• Review and contribute to community-driven improvements.

Tech Stack

• Languages: Java 17+, Spring Boot, Scala
• Build Tools: Maven, Gradle
• Containers & Cloud: Kubernetes, OpenShift, Docker, Azure Container Registry
• CI/CD: Azure DevOps, GitHub
• Integration: Kafka, REST APIs, Service Discovery
• Observability: Prometheus, Grafana, OpenTelemetry
• Security: PKI, mTLS, Token-based Authentication, API Gateways

What you'll bring to the team

Required Qualifications

• 5+ years of Java development experience.
• 3+ years working with distributed systems and microservices.
• Degree in Computer Science or equivalent practical experience.
• Proven experience designing reusable frameworks, libraries, or platform components.
• Strong technical communication and documentation skills.
• Experience supporting developer platforms or engineering communities.

Preferred Qualifications

• Experience building developer-facing frameworks or SDKs.
• Solid knowledge of Spring Boot, Kafka, and event-driven architectures.
• Familiarity with API Gateways, OpenAPI/Swagger, and microservices platforms.
• Experience with Cassandra, PostgreSQL, or other distributed databases.
• Background in financial services or other regulated industries.

Technical Expertise

• Java Ecosystem: Java, Spring Boot, Maven, JVM fundamentals.
• Distributed Systems: Microservices, Service Mesh, Resilience Patterns, OpenTelemetry.
• Security: OAuth2, JWT, PKI, mTLS, Secure Coding (OWASP).
• Cloud & DevOps: Docker, Kubernetes, CI/CD, Azure DevOps, Deployment Strategies.
• Observability: Prometheus, Grafana, Centralized Logging, SLI/SLO/SLA monitoring.

If you want to deep dive into the processing of personal data conducted by ING Hubs Romania during the recruitment process and your rights related to it, read the privacy notices on our website (make sure to scroll until you reach the Data Protection section/ Candidates tab).