Backend Engineer – Java + Kafka, 4-6 years of experience

We are a U.S.-based fintech startup operating in the investment and financial services space. Our distributed teams work across Poland, the United States, and Ireland, collaborating on technology-driven solutions related to stocks and investments.

Security, compliance, and the responsible handling of sensitive financial data are central to how we operate, as we build scalable products in a regulated environment.

Responsibilities

- Develop high-quality Java microservices using Spring Boot.

- Build Kafka producers, consumers, and stream-processing apps.

- Design event-driven architectures with reliability and performance.

- Implement service resiliency patterns such as retries and circuit breakers.

- Collaborate on distributed system design and integration.

- Ensure logging, tracing, and monitoring of backend services.

- Support performance tuning and root cause analysis. 

Skills

- Strong in Java, Spring Boot, microservices patterns.

- Hands-on Kafka development—streams, partitions, consumer groups.

- Knowledge of distributed systems architecture.

- Familiarity with Docker, cloud-native packaging.

- Experience in REST APIs, schema evolution, and contracts.

- Understanding of observability (logs, metrics, traces).

- Good debugging and performance optimization skills

Important: the candidate must have worked/lived in Poland for the last 2+ years

Please read before applying:

The client is building a product in the bank/investment/brokerage systems niche, and their investors have strict security and compliance requirements, where every person will go through a background check.

What does this mean?

Before making an offer, they will check whether you have violated any EU laws.

For background check — you must be a taxpayer in Poland for 2+ years.