Contract Java Backend Engineer - FinTech, Kafka & AWS

Flix; Warszawa; On-site; PLN 83,000 - 124,000; Full time

Job summary

Flix is seeking a Java Engineer on a freelance/service agreement basis to join our finance technology domain. You will build backend features for internal data-heavy applications and support settlement-related workflows across FlixBus entities worldwide.

Ideal candidates have 3+ years of Java experience in a commercial setting, are comfortable with Kafka, AWS, Docker, Kubernetes, and SQL, and can collaborate directly with finance and billing teams to deliver robust solutions.

Qualifications

• 3+ years of experience as a Software Engineer with data processing experience.
• Proven experience with Java in a commercial environment.
• Experience with event-driven architectures, ideally Kafka.
• Experience with cloud providers, ideally AWS.
• Strong SQL knowledge.
• Hands-on with Docker and Kubernetes and CI/CD.
• Familiarity with Snowflake is a plus.

Responsibilities

• Design, build, and maintain internal data-heavy applications for settlement generation.
• Develop and enhance internal services for finance and billing teams.
• Communicate with finance, billing, and partner teams to shape solutions.
• Contribute to product development from refinement to delivery and operations.
• Implement event-driven data processing workflows using Kafka.
• Contribute to infra-as-code, CI/CD on AWS with Docker/Kubernetes and Datadog monitoring.

Skills

Java

Data processing

Kafka

SQL

Docker

Kubernetes

CI/CD

AWS

Event-driven

Tools

Datadog

Snowflake

Job description

Flix is seeking a Java Engineer on a freelance/service agreement basis to join our finance technology domain. You will build backend features for internal data-heavy applications and support settlement-related workflows across FlixBus entities worldwide.

Ideal candidates have 3+ years of Java experience in a commercial setting, are comfortable with Kafka, AWS, Docker, Kubernetes, and SQL, and can collaborate directly with finance and billing teams to deliver robust solutions.