Back-End Developer (ASP.Net)

Fully remote, Poland



A project for a large Client from the Netherlands, consisting of the development of web-based accounting and CRM software.

You will take part in developing the application based on ASP .Net (framework 4.7) on the backend side with React on the frontend side.

The project uses cloud technologies and the CI / CD approach.

Technology stack:



*Customer’s own Webform solution

*MS SQL Server

We are looking for a developer:

  • with at least 3 years of experience in developing .Net applications, especially in ASP.Net,
  • with knowledge of WebForms (framework 4.7) – the Client is in the process of upgrading of the technological stack,
  • who has a good understanding of the implementation of solutions from the development and the use side,
  • who has good written and spoken English (minimum B2).

We offer:

  • B2B: + 26 paid days off and paid sick leaves
  • Fully remote work (it is also possible to work from the office in Wrocław or in hybrid mode)
  • Work in SIENN teams (not outsourced)
  • Longterm projects
  • International training and certifications (Microsoft MCP)
  • Constant personal growth (defined career paths, additional leave for training, training budget) 
  • Medical package and Multisport card
  • Great atmosphere at workplace!


If you have questions about this position, contact me 🤙

Katarzyna Skowronek

HR Specialist

+48 889 783 562

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    Claartje Pothof-van der Zande

    HR Specialist

    +31 24 366 0 466

    Katarzyna Skowronek

    HR Specialist

    +48 889 783 562

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