Ignite innovation with scalable APIs — shape the future of banking technology.
Krakow-based opportunity with hybrid work model.
As a Senior API Developer – Java & Cloud Services, you will be working for our client, a leading financial institution dedicated to transforming digital banking. You will design, build, and optimize secure, scalable APIs that power their cutting-edge digital products and internal platforms, leveraging modern Java and cloud-native patterns to deliver impactful solutions swiftly and reliably. This role offers an excellent platform for technical growth and innovation in a dynamic financial environment.
Your main responsibilities:
- Build and evolve high-performing, scalable APIs and backend services using Java, Spring Boot, and Maven (developed primarily in IntelliJ).
- Collaborate with cross-functional teams, including engineers, product owners, architects, and testers, to deliver robust services aligned with business needs.
- Design APIs following industry standards (REST, GraphQL, SOAP), ensuring versioning, backward compatibility, and optimal consumer experience.
- Integrate with third-party and internal APIs, ensuring resilience, observability, and clear error handling.
- Develop and support event-driven services utilizing Kafka, managing topic design, schema evolution, and message reliability.
- Deploy cloud-ready services on AWS, including Kubernetes / EKS, Fargate, Redis, RDS, S3, Route 53, with consideration for deployment and runtime environments.
- Maintain product quality through automated testing, regular API testing, and troubleshooting live issues with a "you build it, you run it" approach.
- Produce comprehensive API documentation using OpenAPI/Swagger and supporting runbooks as necessary.
- Contribute to engineering standards around security, performance, maintainability, and continuous improvement.
You're ideal for this role if you have:
- At least 5 years of hands-on experience building APIs and backend services in Java.
- Strong expertise with Spring Boot and Maven.
- Solid understanding of backend architecture concepts including service design, data access, caching, and resilience.
- In-depth knowledge of API styles and integration patterns (REST, GraphQL, SOAP).
- Experience working with API tooling such as Postman, Swagger UI / OpenAPI, SoapUI.
- Ability to work with data formats like JSON and XML.
- Proven troubleshooting skills to diagnose issues, fix defects, and enhance performance and reliability.
- Strong collaboration skills and ability to communicate technical decisions effectively.
It is a strong plus if you have:
- Experience with event-driven architecture at scale (Kafka streams, schema registry, idempotency, exactly-once/at-least-once).
- Familiarity with AWS services like Kubernetes/EKS, Fargate, Redis, RDS, S3, Route 53.
- Knowledge of CI/CD pipelines, observability tools (logging, metrics, tracing), and secure coding practices.
- Strong critical thinking and a pragmatic, delivery-focused mindset.
Language Required for the role:
- Fluent English (spoken and written).
Eligibility for the role:
- Only candidates with an existing legal right to work in the European Union will be considered for this role.
#MAKEYourCareerBETTER
Interested? Apply now and include your CV (preferably in English) along with a statement confirming your consent to the processing and storage of your personal data.