Expert Java API Engineer – Payment Processing

Unleash the future of payments — engineer resilient, cloud-ready platforms that power next-generation financial services!

Krakow-based opportunity with hybrid work model.

As an Expert Java API Engineer, you will be working for our client in the financial services industry, helping deliver a future-state architecture for payment processing. You will build lean, reusable payment capabilities focused on high availability, resilience, modernization, and cloud adoption—enabling new products to reach customers faster, with greater quality and efficiency.

Your main responsibilities:

• Deliver engineering expertise for future-state payment processing architecture.
• Design, develop, test, debug, and document high-quality software and API solutions.
• Build highly available and resilient payment processing services using modern microservice architectures.
• Produce architectural artefacts, technical alternatives, data models, and low-level designs.
• Partner with DevOps teams to enable automated infrastructure delivery, DevSecOps value streams, and CI/CD pipelines.
• Provide technical leadership, architecture guidance, mentoring, and consultation to development teams.
• Identify and resolve complex architectural, development, technical, and business issues.
• Support the modernization of the payment estate while ensuring compliance with relevant controls, standards, cybersecurity, and data privacy requirements.

You're ideal for this role if you have:

• A Bachelor’s degree in Computer Science, Engineering, or a related field.
• 15+ years of applied experience as an API Engineer and 10+ years of software engineering experience.
• 10+ years of programming experience in Java.
• Expert knowledge of distributed systems, microservices, and Spring Boot.
• Strong expertise in Docker, Kubernetes, service mesh, Kafka, and Kubernetes CNI.
• Experience with API design, application security, authentication, caching, middleware, and architectural documentation.
• Expertise in JVM tuning, diagnostics, troubleshooting, and performance optimization.
• Practical knowledge of cloud and DevOps technologies, including VPC/firewall, IAM, cloud sizing and costing, monitoring, and observability tools such as Splunk, Grafana, Prometheus, Jaeger, Kiali, and OpenTelemetry.

It is a strong plus if you have:

• Experience with Go and Rust programming languages.
• Expert-level SQL coding abilities.
• Experience working in a financial institution, ideally within payments.
• Experience with distributed databases.

Language Required for the role: Fluent English, both written and verbal.

Eligibility for the role: Only candidates with an existing legal right to work in Europe 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.

Tech stack

• Java
• Spring Boot
• Microservices
• API Design
• Kubernetes
• Apache Kafka
• Docker
• JVM Tuning & Performance Optimization
• Cloud & DevOps Technologies
• GO / RUST