Senior Java Engineer for Scalable Fintech Platforms

Mastercard Inc.; Oslo fylke; On-site; NOK 900,000 - 1,200,000; Full time

Job summary

Mastercard Inc. in Oslo, Norway seeks a Senior Software Engineer specialized in Java to design, build, and evolve scalable software solutions that deliver real business value. You will influence architectural decisions and drive engineering excellence across teams and production systems.

You will lead design conversations, write high-quality code, and mentor junior engineers while collaborating with product, architecture, and operations to enable end-to-end solutions in a fast-paced environment.

Qualifications

• Strong experience in software development across modern technologies and architectures.
• Solid understanding of system design, APIs, and scalable distributed systems.
• Writes clean, efficient, and well-tested code, with strong debugging and problem-solving skills.
• Experience from fintech, open banking, bank APIs, ERP integrations or accounting software environments.
• Has experience with test strategies and quality practices across the SDLC.
• Is comfortable working in complex, multi-tiered systems and production environments.
• Communicates clearly and effectively across technical and non-technical stakeholders.
• Shows ownership, accountability, and a drive to deliver high-quality outcomes.
• Is proactive in identifying improvements and driving change.
• Enjoys mentoring others and contributing to a strong engineering culture.
• Thrives in a collaborative and agile environment.

Responsibilities

• Design, develop, and maintain scalable and reliable software solutions aligned with business needs.
• Contribute to architecture and technical design decisions across systems and services.
• Write high-quality, maintainable, and well-tested code.
• Perform code reviews and ensure adherence to engineering standards and best practices.
• Lead or actively contribute to planning, prioritization, and backlog management.
• Troubleshoot and resolve complex technical issues across systems and environments.
• Ensure high levels of quality through testing strategies (unit, integration, performance, etc.).
• Collaborate with cross-functional stakeholders (product, architecture, operations) to deliver end-to-end solutions.
• Drive continuous improvement of development practices, tools, and processes.
• Mentor and guide junior engineers, fostering a culture of learning and collaboration.

Skills

Software development

System design

APIs

Distributed systems

Code quality

Testing

Mentoring

Agile

Job description

Mastercard Inc. in Oslo, Norway seeks a Senior Software Engineer specialized in Java to design, build, and evolve scalable software solutions that deliver real business value. You will influence architectural decisions and drive engineering excellence across teams and production systems.

You will lead design conversations, write high-quality code, and mentor junior engineers while collaborating with product, architecture, and operations to enable end-to-end solutions in a fast-paced environment.