Senior .NET Backend Developer

Permanent employee, Full-time · Budapest

Your mission

Are you an enthusiastic senior C# backend developer, ready to take the next step in your career?

You like exciting projects, using new development technologies? 

Interested in the telecommunications industry?


As a member of our team you will contribute to the continuous development, design, documenting and testing of the IT systems developed and operated by our telecommunications company.

Your profile

Major responsibilities and tasks

  • design and implement main modules independently
  • cooperate in the software and database architecture design
  • support the decision making processes by database analysis
  • participate in the research of new technologies related to the system, present ideas for system improvements
  • based on your experience, you might also have the possibility to take part in the design, development of the API, Library that supports our business software


Required qualifications and skills

  • at least 3+ year experience as a software developer
  • high level expertise in .NET framework and C# language
  • Working experience with Entity Framework
  • knowledge of web applications and web services (ASP.NET, MVC, SOAP, REST)
  • proficiency in MSSQL database (design, scaling, optimizing queries)
  • deep understanding of the Windows Operating Systems (services, APIs)
  • independent problem-solving skills
  • good command of English



  • Bachelor’s or Master’s in Computer Science, Engineering, Physics, Math, or related work experience.
  • Familiarity with HTML, CSS/Bootstrap
  • Knowledge of Javascript/Typescript
Why us?

We are offering

  • professional challenges, inspiring, diverse tasks
  • structured development process
  • learning path on new technologies (AI, LLM)
  • multicultural environment
  • flexible working hours and home office days
  • relaxed atmosphere, steady, supportive international team
  • easily accessible modern office with good infrastructure
  • complimentary coffee, fruits and snacks
About us
Telio is a medium-sized, internationally active, rapidly growing company in the field of telecommunications and IT services in the prison sector. As the European market leader, we have been providing communications solutions for prisons and their inmates worldwide for 25 years. With more than 270 employees, we are active in 25 countries and develop, install and operate communication and media systems that make an important contribution to resocialization in prisons as well as in correctional facilities.
We are looking forward to hearing from you!
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