Senior Software Engineer

At Medius, we believe finance should empower strategy, not stress. Founded in Sweden in 2001, we’ve grown from a local startup into a global leader in cloud-based spend management. Thousands of organizations trust our AI-powered solutions to simplify processes, eliminate manual work, and give finance teams clarity, confidence, and control. 

We’re more than a software company – we’re a global team of problem-solvers and innovators reinventing accounts payable. Our culture thrives on freedom, curiosity, and continuous improvement, giving you space to focus on what matters – and still have time to live your best life. 

If you want to make a real impact, see your ideas come to life, and shape the future of finance, Medius is the place for you. 

Job overview

We are looking for a highly skilled Software Engineer to join our Kraków-based team as we scale our next-generation, true cloud service. Supporting over 1,000 global clients, our main platform is built on a modern stack of Azure, .NET Core, React, and TypeScript. In this role you will do more than write code; you will influence the product’s future by designing scalable solutions and championing the integration of AI to revolutionize our development lifecycle. Success in this role means balancing high-velocity feature delivery with long-term architectural health.

What you'll do:

• Architect and develop scalable, high-quality cloud services, ensuring they meet the demands of a global client base.

• Master Domain-Driven Design (DDD) principles to build modular, maintainable, and highly performant software components.

• Drive AI Integration with use of AI tools (e.g., GitHub Copilot, LLM-based assistants) to automate code generation, refactoring, documentation, and unit testing.

• Design RESTful Web Services that facilitate seamless communication within our complex cloud infrastructure.

• Optimize Azure Services to ensure our infrastructure is not only performant and scalable but also cost-effective and secure.

• Collaborate within cross-functional teams of engineers, product owners, and designers, fostering a culture of mutual support and accountability in an agile environment.

• Champion code excellence by implementing best practices in code testing, maintaining quality standards, and providing insightful code reviews.

• Innovate and automate by investigating emerging technologies and AI trends to reduce manual overhead and accelerate team velocity.

Qualifications

• Experience: 4+ years of professional experience in software development, with deep proficiency in C# and .NET technologies.

• Frontend proficiency: solid hands-on experience with React (or similar frameworks) and TypeScript/JavaScript.

• Architectural expertise: proven experience with (or deep understanding of) DDD and CQRS patterns.

• Practical experience in designing, deploying, and maintaining services within Microsoft Azure.

• AI & automation skills: demonstrated interest or experience in using AI-driven tools to automate development workflows and increase personal and team productivity.

• Data & API design: strong experience with relational databases and the design of robust RESTful APIs.

• Quality focus: a background in rigorous code testing practices and maintaining high-quality software code.

• Education: degree in Computer Science, Engineering, or a related field (or equivalent proven experience).

• Communication: English proficiency at B2 level or above, with the ability to articulate complex technical concepts to diverse stakeholders.

• A strong sense of ownership over your work and a commitment to continuous learning and knowledge sharing.

Why Medius: 

• Well-being perks: Multikafeteria program, private healthcare (LuxMed), life insurance 

• Fun & connection: Summer & Christmas parties, Game Board nights, spontaneous team events 

• Growth & impact: Be part of a team where your ideas matter, innovation thrives, and your work is visible globally