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

What you’ll be doing

  • 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. 

What you get in return

  • Flexible cooperation model – choose the form that suits you best
    (B2B, employment contract, etc.)
  • Hybrid work setup – 6 days a 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 

Who we’re looking for

  • 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. 

Software Security Backend Engineer (Java)

Kraków

B2B

1200 - 1450 PLN/md +VAT

SUPPORT & BENEFITS

Private healthcare

Fast access to doctors and medical tests. 

Mindbox fully covers the individual package. You can extend the coverage to your partner and family on preferential terms. A wide network of medical providers and clear rules for everyday use.

Multisport

Energy that pays off.

We cover 50% of the card cost. You get access to thousands of sports facilities across Poland, plus a convenient mobile app. Additional cards for family members are available.

Training & development

Practical support for your career growth.

We co‑fund courses, certifications and conferences under a clear Training Policy. You also get access to a library of recorded webinars and trainings – available whenever you need them.

Eyewear or contact lenses co‑funding

Clear vision means comfortable work.

Up to PLN 500 every two years, with an additional PLN 300 available in justified cases. Simple reimbursement, regardless of your form of cooperation.

Group life insurance

Real protection from day one.

Option I is fully funded by Mindbox, Option II is co‑funded. You can include your partner and adult children, with coverage that also applies to treatment and hospitalisation abroad.

Ongoing support from the Talent Network Development

You’re not on your own in a project.

Regular contact, quick response and a partnership‑based approach. You focus on your work — we help take care of the rest.

Regular integration meet‑ups

Relationships that work beyond the project.

Cyclical meet‑ups for contractors in major cities across Poland. A space to talk, exchange experience and stay in real contact with the Mindbox team.

Annual company‑wide integration

One event. The whole community.

A two‑day company gathering with accommodation, transport and a full activity programme. Time to connect teams from across Poland and build shared experiences.

New baby gift

Important moments matter to us.

When a child is born, we prepare a personalised gift. All it takes is a short message to the Talent Network Development team.

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the recruitment process

We support you at every stage

Submit your CV

Apply directly for a selected job offer or simply send us your CV.

Recruiter call

If your profile matches the role or we have a good opportunity for you, a recruiter will get in touch with you.

Profile shared with the client

After the call, we recommend your profile to the client. This is your first real step toward a specific project.

Project interview

If the client wants to proceed, we arrange the meeting. We prepare you for the interview and stay in close contact.

Feedback and decision

You receive feedback regardless of the outcome. If it’s a match, we present an offer.

Contract 100% online

All formalities are handled remotely. Fast, convenient and straightforward.

Ongoing support

Our IT Talent Network team supports you throughout the entire project.

Referral Program

Refer a friend & get up to 6,000 PLN

Do you know an IT specialist who could be a good fit for one of our projects? Share their contact details with us and we’ll take care of the rest.

You can receive up to 6,000 PLN for a successful referral.