Software Security Backend Engineer (Java)

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

We’re looking for a highly skilled backend engineer with both strong hands-on coding expertise and deep security knowledge to shape next-generation security solutions. You will design and build secure, scalable services using modern Java, Spring Boot, and cloud-native technologies, contributing to a Zero Trust platform for one of the world’s leading financial institutions.

This is more than just coding — you’ll drive industry best practices, mentor other engineers, and influence technology direction across a broad engineering community.

Sounds like your kind of challenge? 

#LI- Hybrid – 6 days a month from the office in Kraków

• Design, build, and deploy secure backend services leveraging Java 21 (Virtual Threads/Project Loom) and Spring Boot 3.x
• Implement Zero Trust architecture principles and OAuth2/OpenID Connect at the code level
• Build solutions optimized for Google Kubernetes Engine (GKE) and databases such as Cloud Spanner or Cloud SQL (Postgres)
• Develop event-driven architectures using Pub/Sub or Kafka
• Automate from the outset: reduce manual toil and accelerate secure delivery pipelines
• Apply best practices for software security across SDLC
• Research new technologies, guide adoption, and set the technical direction for the platform
• Mentor engineers and foster a culture of technical excellence and knowledge sharing
• Actively contribute to engineering communities and “raise the bar” in delivering secure, high-quality solutions
• Stay ahead of industry trends and communicate changes effectively to influence adoption

Note: Detailed project information will be shared during the recruitment process. 

• Expert knowledge of Java 21+ (including JVM internals, memory management, Project Loom) and modern Spring ecosystem
• Solid experience with secure coding practices and building authentication/authorization flows using OAuth2/OpenID Connect
• Proven experience with Google Cloud Platform components (particularly GKE, Cloud Spanner, Cloud SQL)
• Strong practical experience in event-driven architecture with Kafka or Pub/Sub
• Demonstrated ability to think strategically about risk, security, and future technology adoption
• Influential leadership skills: capable of transferring expertise and guiding teams across the organization
• Hands-on problem-solving mindset, adaptable across multiple domains (not just a network or back-end specialist, but a generalist who thrives on complex challenges)
• Demonstrated thought leadership via technical blogs, open-source contributions, or community engagement is a plus

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. 

Submit your application! We look forward to reviewing your profile 😊 

Know someone who might be a great fit? 
Feel free to share this opportunity using the referral link: Mindbox Referrals System