Senior Back-End Developer

Fully remote, Poland

Job description

Role: As a Backend Developer, you will be responsible for driving backend project ownership, delivering second-level support, and actively promoting continuous improvements across systems, processes, and code quality. This role involves managing both legacy and modern projects while working independently within a small team environment. The ideal candidate is a proactive problem solver, adaptable across diverse systems and technologies, and thrives in dynamic, multi-project settings.

What we offer:

  • B2B rate: up to 140 PLN/h
  • Work in an international project environment
  • Access to international training and certifications (e.g. Microsoft MCP)
  • Opportunities for professional development and knowledge sharing
  • Possibility to access optional benefit platforms (medical care, sports card, insurance, language courses)
  • Collaborative and supportive project environment

Job requirements

Required skills & experience

  • Advanced experience with MS SQL Server (T-SQL), including stored procedures, functions, and error handling
  • Strong background in .NET backend development
  • Proficiency in C#
  • Hands-on experience with the Azure environment
  • Familiarity with Azure DevOps
  • Ability to write clean, maintainable, and well-documented code
  • Understanding of deployment processes and release pipelines
  • Openness to and experience with AI-assisted development tools
  • Strong problem-solving skills and attention to detail
  • Proficiency in English (spoken and written)
  • Proactive and self-driven mindset

Nice to have:

  • Experience with Supabase (PostgreSQL)

Soft skills:

  • Openness in communication within an international team, including constructive challenge and initiative-taking
  • Proactive attitude and willingness to take ownership
  • Ability to collaborate effectively in a distributed, multicultural environment

Interested?

If you have questions about this position, contact me 🤙

Joanna Wanat

IT Recruitment Specialist

+48 535 566 194

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    Claartje Pothof-van der Zande

    HR Specialist

    +31 24 366 0 466

    claartje.pothof@sienn.com

    Aneta Zawieja

    HR Specialist

    +48 535 566 283

    aneta.zawieja@sienn.com

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