Senior Backend Engineer — Connectivity & Open Banking

Mastercard Inc.; Województwo pomorskie; On-site; PLN 280,000 - 420,000; Full time

Job summary

Mastercard is seeking a Lead Software Engineer for the Open Finance Europe – Connectivity team, based in Poland. You will own end-to-end delivery of secure, reliable connectivity services, solving complex problems and guiding technical decisions.

This hands-on role focuses on API design and backend systems, delivering high-quality solutions across markets. Collaborate with Product, Architecture, Security and SRE to scale integrations, improve platform reliability, and drive CI/CD and security

Qualifications

• 8–10 years of professional software engineering experience.
• Strong hands-on experience building cloud-based, highly available systems.
• Deep expertise in backend engineering (API design, reliability, production support).
• Proven ability to solve complex technical problems and influence design decisions.
• Experience delivering and operating end-to-end systems in production environments.
• Strong collaboration skills with Product and business stakeholders.
• Familiarity with banking/payments/open banking (PSD2) environments.
• Strong communication and problem-solving skills.

Responsibilities

• Own end-to-end delivery of engineering solutions—from design through development, deployment, and production support.
• Solve complex technical problems and drive system design decisions.
• Design, build, and operate scalable APIs and backend services.
• Review code and uphold high standards of quality, performance, and maintainability.
• Apply best practices across SDLC, testing, security, and observability.
• Collaborate with Product, Architecture, Security, and SRE teams.
• Implement robust testing strategies (unit, integration, end-to-end).
• Drive automation and improvements in developer productivity and operational efficiency.
• Mentor engineers and support them in solving technical challenges and growing their skills.

Skills

Backend engineering

API design

System reliability

Production support

Collaboration

Communication

PSD2/open banking familiarity

Tools

C#

.NET

Web APIs

Java/Spring Boot

Azure

AWS

PostgreSQL

Flyway

Generative AI tools

Job description

Mastercard is seeking a Lead Software Engineer for the Open Finance Europe – Connectivity team, based in Poland. You will own end-to-end delivery of secure, reliable connectivity services, solving complex problems and guiding technical decisions.

This hands-on role focuses on API design and backend systems, delivering high-quality solutions across markets. Collaborate with Product, Architecture, Security and SRE to scale integrations, improve platform reliability, and drive CI/CD and security