API Developer

At Mindbox we connect top IT talents with technology projects for leading enterprises across Europe.  

We’re seeking an API Developer with strong Java expertise to work within a  cross-functional engineering team , responsible for delivering secure, high-performing services at scale. You’ll be working with  modern Java, Spring Boot , and  cloud-native patterns  including  API-first design  and  event-driven architecture  on AWS.

Sounds like your kind of challenge?  

#LI- Hybrid – 8 days per month from the office in Kraków

What you get in return

Flexible cooperation model – choose the form that suits you best (B2B, employment contract, etc.)

Hybrid work setup – 8 days per month from the office in Kraków

Collaborative team culture – work alongside experienced professionals eager to share knowledge 

Continuous development – access to training platforms and growth opportunities 

Comprehensive benefits – including Interpolska Health Care, Multisport card, Warta Insurance, and more 

High quality equipment – laptop and essential software provided

Daily tasks

• Design, build, and maintain scalable APIs and backend services using Java, Spring Boot, Maven
• Collaborate closely with product owners, architects, and testers to deliver high-quality, business-aligned solutions
• Design APIs following industry standards (REST, plus GraphQL/SOAP where applicable) ensuring versioning, backward compatibility, and resilience
• Integrate internal and third-party APIs with robust error handling and observability
• Build event-driven services with Kafka or similar: manage topics, schema evolution, and message reliability
• Deploy on AWS using EKS/Kubernetes, Fargate, Redis, RDS, S3, Route 53
• Maintain quality through automated testing, performance tuning, and production support in line with the “you build it, you run it” principle
• Produce API documentation using OpenAPI/Swagger and update runbooks as needed
• Contribute to security-by-design practices and continuous improvement

Requirements

Proven back-end development experience in  Java

Strong hands-on expertise with  Spring Boot  and build tools (e.g., Maven)

Solid knowledge of  API architecture  and integration patterns (REST, GraphQL, SOAP)

Experience with common  API tools  like  Postman, Swagger/OpenAPI, SoapUI

Familiar with data formats ( JSON, XML ) and backend fundamentals (caching, resilience, service design)

Ability to  diagnose issues, optimize performance, and deliver reliable solutions

Great  collaboration skills  and clear technical communication

Nice to Have

Experience with  event-driven architecture  and  Kafka  at scale

Familiarity with  AWS cloud services  (Kubernetes/EKS, Fargate, Redis, RDS, S3, Route 53)

Understanding of modern  CI/CD pipelines, security practices, and observability tools

Strong analytical mindset with a pragmatic, delivery-focused approach

Joining this project you’ll become part of Mindbox – a tech-driven company where consulting, engineering, and talent meet to build meaningful digital solutions. We’ll back you up every step of the way, accelerate your development, and ensure your skills make a difference.

Must have: Java, Spring Boot, Maven, API, REST API, GraphQL, SOAP, Postman, Swagger, OpenAPI, SoapUI, JSON, XML, Service design

Nice to have: Kafka, AWS Cloud, Kubernetes, Amazon EKS, AWS Fargate, Redis, Amazon RDS, AWS S3, Route, CD pipelines, Security