Senior Software Engineer .NET C# - Expense Management

Senior Software Engineer .NET C# - Expense Management

Rydoo · Warsaw, Poland (Hybrid) · Full-time · Posted 2026-04-01

Workplace: hybrid

Department: Product Development

Description

We’re Rydoo, an AI-driven B2B SaaS company that simplifies how businesses manage spend, from employee expenses to supplier invoices.

Our two business lines—expense management and accounts payable—help finance teams work more efficiently and stay in control of company spending. Our expense management platform makes submitting, approving, and reimbursing expenses easy, while our accounts payable solution uses AI to automate invoice processing and approval workflows.

Behind our products is an international team of more than 250 colleagues. Join us to solve practical challenges, take ownership of your work, and help develop technology that finance teams rely on every day.

Rydoo in a snapshot

• Ambitious international team
• 40+ nationalities speaking over 15 languages
• 250+ employees across multiple countries
• Easy-to-use spend management app available on iPhone and Android
• Supporting over 10,000+ clients and 1 million+ users worldwide
• 4.5 employer score on Glassdoor
• Hybrid work policy

The Role

At Rydoo, we build smart, simple solutions that help people spend less time on expenses and more on what matters.

As a Senior Software Engineer, you will:

• Work in one of our squads, a cross-functional, autonomous team.
• Shape the core of our product - designing and extending systems that make expense management faster and smarter for thousands of users worldwide.
• Bring valuable features into production and follow up on their performance and maintenance.
• Contribute on front-end features.
• Design and implement REST APIs.
• Help architect several of our microservices.
• Design and write automated tests.
• Setup infrastructure and pipelines via Infrastructure as Code (IaC).

Requirements

• Several years of experience with backend development.
• Excellent knowledge of .NET, C#.
• Good knowledge of Entity Framework (or any ORM like NHibernate), SQL Server or similar.
• A team player with a passion for writing clean and testable code within a cross-functional team.
• Experience in optimising the performance and scalability of applications to support our ever-growing user base.
• Experience with Service Oriented Architecture using Service Bus to connect everything is a plus.
• Knowledge of Azure Cloud (or AWS, GCP) is a plus.
• Some experience with Angular is a plus, but having the curiosity and willingness to learn front-end technologies is also much appreciated.
• Agile and DevOps experience is a plus.
• Experience with LLMs is a plus.
• Ability to stay up-to-date with industry trends, best practices, and emerging technologies to continuously improve our development processes and drive innovation.
• A degree in computer sciences or a related field is preferred, but any equivalent experience is just as valuable.

Benefits

Next to our amazing team, informal & international company culture and our mission to become the number 1 spend and invoice management platform in Europe, we offer some nice benefits that make working at Rydoo even more fun:

• A competitive package, including salary and benefits
• €1000 / year learning and development budget
• Rydoo Hybrid Work Policy: flexibility to work from home while also fostering team collaboration in our Warsaw hub 1x a week.
• Rydoo On Tour: our international mobility program that gives employees the possibility to temporarily relocate to one of the countries we have a Rydoo office.
• Professional freedom and a flexible work environment
• Upskilling through training and coaching programs
• Regular company and team events
• Wonderful international team with more than 33 different nationalities
• Spectacular onboarding program for all new Rydooer’s
• Permanent contract

Why Join Us

At Rydoo, we celebrate diversity and are committed to creating an inclusive environment for all employees. We value and encourage ongoing learning opportunities and career progression.

Even if you don't tick every box but see yourself contributing, we encourage you to apply. We're more interested in finding a well-rounded individual with a can-do attitude. Your passion, dedication and desire to learn are what matter most to us.

Check us out

LinkedIn: https://www.linkedin.com/company/rydoo

Glassdoor: http://bit.ly/2UujjWJ

Instagram: https://www.instagram.com/wearerydoo/

YouTube: https://www.youtube.com/channel/UCTZYj7vm_ZcsGFL18jWHt_A

Inside Rydoo Blog: https://www.rydoo.com/inside-rydoo/

Apply

Apply at Rydoo

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