Back-end developer
Kassavirtanen Oy · Finland
Onsitemid💰 4,200–5,100 EURTech · SoftwarePosted 16.09.2026 klo 14.55
Skills
C#.NETSQLREST APIGitsoftware architecturescalability
Job Description
Who we are
Kassavirtanen Oy is a growing invoicing service company that designs and develops its own systems, websites, and digital services for businesses. We operate from a modern office in the heart of Helsinkis Kamppi district, where teamwork and open communication are at the core of everything we do.
We focus on high-quality code, long-term development, and understanding our clients' businesses. You will have the opportunity to work on meaningful projects that matter to us and our clients.
Your role with us
We are now looking for a Back-End Developer who is passionate about building scalable and efficient back-end systems.
You will work as part of our development team, designing and implementing back-end services and APIs that power both our own systems and custom web services for our clients. In collaboration with front-end developers and designers, you will help build powerful solutions that provide smooth and seamless user experiences.
Technologies we use:
C# / .NET – for back-end development
SQL – working with databases and integrations JavaScript – basic knowledge for handling API integration and client-side logic REST APIs – building and maintaining APIs for web services and systems Familiarity with cloud platforms (Azure, AWS) and DevOps practices is a plus What we expect from you:
Previous experience in back-end development (at least 2 years) Strong knowledge of C# / .NET and SQL databases Experience with designing and building REST APIs Ability to write clean, efficient, and maintainable code Experience working with version control (Git) Understanding of application architecture and scalability Teamwork skills and a willingness to learn Fluent in Finnish or English What we offer you:
Interesting projects with the opportunity to influence their implementation A supportive work environment and colleagues who will help you grow A modern workspace in a cozy office in the heart of Kamppi A competitive salary and excellent employee benefits Interested?
We review applications and conduct interviews throughout the application period, so we encourage you to apply as soon as possible by sending us your cover letter, CV, and salary expectation.
You are also welcome to send us an open application, as we are always interested in hearing from talented people. Please remember to indicate in your application which position you are applying for.
Please send the application via digital application portal: https://account.jobportal.fi/tyopaikat/back-end-developer/171983JP211716/hae