Senior Java Engineer

This position is listed on behalf of a partner company, which manages all applications and next steps. Our partner is looking for a Senior Java Engineer (Payments) based in Austria. Join a specialized engineering environment where you will design and deliver secure, scalable, and high-performance payment platforms for leading organizations in the global financial services industry. As a Senior Java Engineer, you will take end-to-end technical ownership of mission-critical systems that process financial transactions reliably and efficiently. You will lead architectural decisions, build robust integrations, and ensure the highest standards of performance, security, and regulatory compliance. Working with modern Java technologies, cloud infrastructure, and event-driven architectures, you will tackle complex engineering challenges across multiple clients and platforms. You will also help shape engineering best practices, mentor fellow developers, and drive continuous improvements across the software development lifecycle. This fully remote opportunity offers the variety of a specialist payments consultancy, combining technical leadership, international collaboration, and meaningful impact on the infrastructure powering global transactions. Accountabilities:
- Design and develop scalable applications: Build, maintain, and optimize enterprise-grade applications using Java and Spring Boot, taking ownership of features from initial design through production deployment.
- Lead technical architecture: Define service boundaries, data models, integration patterns, and non-functional requirements for complex software components, ensuring solutions are reliable, maintainable, and scalable.
- Deliver payment technology solutions: Develop and maintain payment platforms and integrations with external systems, APIs, and third-party providers, supporting secure and efficient financial transactions.
- Ensure reliability and compliance: Take responsibility for application performance, availability, security, and adherence to applicable regulatory and industry standards.
- Build event-driven systems: Develop robust asynchronous processing workflows using Apache Kafka, applying appropriate approaches to idempotency, transaction consistency, and reliable message handling.
- Collaborate across disciplines: Work closely with product managers, solution architects, and DevOps engineers to translate business requirements into effective technical solutions while evaluating and challenging design trade-offs where necessary.
- Improve engineering practices: Strengthen CI/CD pipelines, automated testing, observability, and deployment processes to improve delivery speed, software quality, and operational resilience.
- Promote code quality and technical excellence: Write clean, efficient, testable code, lead code reviews, establish engineering best practices, and mentor junior and mid-level engineers.
- Manage production incidents: Investigate operational issues, conduct root-cause analyses, and implement sustainable fixes that prevent recurrence and improve system reliability.
- Leverage AI-assisted development: Integrate AI coding assistants and large language models into daily development workflows for implementation, refactoring, testing, debugging, and documentation, while validating their output for correctness, security, and maintainability.

Requirements:
- Professional

experience:
At least seven years of professional Java development experience, including responsibility for designing, delivering, and operating complex production systems.
- Payments and fintech expertise: Hands-on experience building or operating payment or financial technology systems, such as card issuing, acquiring, transaction processing, authorization, settlement, or cross-border payments. A strong understanding of transaction lifecycles, reconciliation, idempotency, and regulatory constraints is essential.
- Advanced Java and Spring expertise: Strong knowledge of Java 21 or later, including relevant long-term support releases, and experience with Spring Boot and modern Spring Framework technologies for building RESTful and event-driven microservices.
- Event-driven architecture: Practical experience with Apache Kafka, asynchronous processing, idempotent operations, and exactly-once processing semantics.
- Database technologies: Proficiency with relational databases such as PostgreSQL and MySQL, along with ORM technologies including Hibernate and JPA.
- API design and integration: Strong experience designing REST APIs, working with OpenAPI specifications, and implementing reliable integrations with external systems and third-party services.
- Build and delivery tooling: Experience with Gradle, Maven, and CI/CD pipelines, with familiarity with tools and technologies such as GitHub Actions, Helm, and Terraform.
- Cloud and containerization: Hands-on experience with AWS, Docker, and Kubernetes, including deploying and operating applications in m