Role: Senior Java Backend Developer- Payments AI Enabled Spec Driven Development
Location: Gdynia and Warsaw, Poland
Hybrid - 3 Days
Extensive years in Java backend development including hands on years in payments or banking
Role Summary
We are looking for a senior Java backend developer with hands on payments experience to design and build secure high-performance payment services The candidate should be expert in Core Java Spring Boot microservices and Kafka They should also use AI-assisted engineering especially spec driven development to deliver high-quality software faster Working directly with Nordic client stakeholders they will own solutions from specification through to production
Key Responsibilities
- Design develop and maintain scalable payment microservices for payment initiation clearing settlement and reconciliation
- Build event-driven high throughput flows using Kafka with idempotency exactly once handling and reliable retry and error handling
- Write clear specifications requirements acceptance criteria API contracts data models and use them as the single source of truth for AI-assisted design code generation and testing
- Use AI coding assistants and agents eg GitHub Copilot Spec Kit or similar to turn specifications into plans tasks code and tests Critically review all AI-generated output for correctness security and compliance
- Design REST APIs contract first using OpenAPI and keep specifications and code in sync
- Make sure solutions meet banking grade standards for security resilience audit and data protection
- Work with product owners architects and testers in Agile SAFe teams Mentor other developers on modern Java and AI-assisted engineering practices
- Support production and analyze incidents for business-critical payment systems
Required Skills
Java and backend
- Expert in Java 17 Java 21 preferred Spring Boot 3 Spring Framework Spring Data Hibernate JPA
- Spring Security with OAuth2OIDC JWT and mTLS
- Microservices patterns API gateway circuit breaker saga outbox CQRS and event sourcing
- Kafka producers consumers partitioning schema registry Kafka Streams
- Contractfirst REST API development OpenAPISwagger API versioning and documentation
Payments domain
- Handson experience with ISO 20022 messages pain pacs camt and SWIFT MTMX migration
- Knowledge of SEPA Credit Transfer SEPA Instant SCT Inst SEPA Direct Debit and real-time payment schemes such as TIPSRT1
- Understanding of the payment lifecycle initiation validation screening routing clearing settlement and reconciliation
- Awareness of EU regulation including PSD2Open Banking APIs the EU Instant Payments Regulation DORA GDPR and AMLsanctions screening
AI and specdriven development
- Practical experience with spec-driven development writing structured testable specifications that drive AI-generated design code and tests
- Skilled use of AI coding assistants and agents in daily development prompt and context engineering iterating on output generating tests
- Ability to validate AI-generated code for quality security and performance and to apply guardrails such as code review static analysis and policy checks
- Understanding of responsible AI in regulated environments no sensitive data in prompts traceability human oversight
Data and databases
- Strong relational database skills Oracle MS SQL PostgreSQL complex queries performance tuning transactions and locking
- Database migration tools Flyway Liquibase
- DevOps and quality
- Docker and Kubernetes OpenShift a plus
- CICD Git Maven Bamboo Jenkins GitHub Actions Ansible artifact repositories Nexus Artifactory
- Testing JUnit 5 Mockito Test containers contract testing Pact Spring Cloud Contract performance testing
- Code quality and security SonarQube static and dependency security scanning SASTSCA OWASP Top 10
- Shell scripting and scheduling tools UC4Automic AutoSys ControlM
Ways of working
- Experience in Agile and SAFe delivery
Good to Have
- Cloud platforms Azure AWS GCP
- Observability Grafana Prometheus OpenTelemetry AppDynamics ELK Splunk
- Experience with Nordic banks or payment providers
- Older stacks for maintenance work WebLogic Tomcat JSP JavaScript Bootstrap
- Certifications Oracle Java Spring Professional Kubernetes CKAD cloud certifications
Skills
Mandatory Skills : AI/Generative AI, Java, Java Microservices, Java Spring-Boot, Kubernetes
Good to Have Skills : Agile (Value-Driven Delivery), Docker, Java Spring Cloud, JavaScript, Payments (SWIFT, ISO20022, Real-Time, Instant, Request to Pay, Domestic, Cross-Border, High Value, Low Value and Mass Payments)
Recruiter's Email : [email protected]