Lead Software Engineer — Connectivity
Summary
Lead Software Engineer on Mastercard's Open Finance Europe – Connectivity team in Warsaw, owning end-to-end delivery of secure, scalable API connectivity to financial institutions. Hands-on backend work primarily in C#/.NET on Azure (plus AWS and Java/Spring Boot), covering design, testing, automation, production support, and mentoring.
Our Purpose
Title and Summary
Lead Software Engineer — ConnectivityOverviewThis role sits within Mastercard’s Open Finance Europe – Connectivity team, building and operating scalable API connectivity to financial institutions across Europe.
As a Lead Software Engineer, you will own end-to-end delivery of secure, reliable connectivity services. This is a hands-on role focused on solving complex problems, driving technical decisions, and delivering high-quality systems from design through production.
You will partner with Product and business stakeholders to deliver new capabilities, improve platform reliability, and scale integrations across markets.
Core 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
Technology Stack
• C#, .NET 10, Web APIs
• Java/Spring Boot (plus)
• Azure (App Services, Blob Storage, KeyVault, CI/CD)
• AWS (Microservices, S3, Redis, CI/CD pipelines)
• PostgreSQL, Flyway
• Generative AI tools (GitHub Copilot, etc.)
All About You
Must Have
• 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
Nice to Have
• Experience with Open Banking or bank connectivity at scale
• Experience with AI-assisted engineering tools (Copilot, etc.)
• Track record of improving efficiency through automation
• Familiarity with infrastructure-as-code and platform governance
Corporate Security Responsibility
All activities involving access to Mastercard assets, information, and networks comes with an inherent risk to the organization and, therefore, it is expected that every person working for, or on behalf of, Mastercard is responsible for information security and must:
Abide by Mastercard’s security policies and practices;
Ensure the confidentiality and integrity of the information being accessed;
Report any suspected information security violation or breach, and
Complete all periodic mandatory security trainings in accordance with Mastercard’s guidelines.