Senior Developer-Java

Job Description:

We are looking for Senior Software Developers who will take senior responsibilities in analysis, design, development, test and integration phases of call processing focused telecom software projects in an Agile development environment.


  • Designing and developing SIP/RTP based VoIP services and frontend/backend of their web interfaces.
  • Analyzing requirements and building use cases.
  • Contributing to test, integration, documentation and issue resolution phases of software development projects.
  • Leading, guiding and training others.
  • Excellent teamwork and problem-solving skills.


  • Minimum 3 years of development experience in Java/J2EE applications and telecom call processing projects.
  • Knowledge and experience with SIP protocol.
  • University degree in computer sciences, electronic engineering or related fields.
  • Having knowledge and experience in the following;
  • VoIP, SIP, SDP, RTP, TCP/IP protocols and 3GPP specifications.
  • Advanced Java/J2EE, C, C++ and JNI.
  • Java Profiling: Memory usage, garbage collection, CPU usage and thread usage analysis and optimization.
  • Capacity and performance testing.
  • Web Services (SOAP, REST).
  • Web user interface knowledge with JavaScript, JSP, JSF, CSS.
  • Fluency in English (both verbal and written) – required for attending international video conferences.
  • Knowledge of agile design methodology.
  • Strong technical documentation and verbal/written communication skills.

Life at Orion Europe

Orion offers an immersive, energetic work environment where employees can innovate. We encourage you to join us at one of our locations in Serbia, Türkiye, Romania and Lithuania.

Work Environment

Orion is a leading digital transformation and product development services firm. In Europe we have delivery locations around Belgrade, Istanbul, Bucharest and Vilnius. Our teams are focused on digital product development for major global companies and unicorn start-ups. Our engineers are immersed with our clients to deliver innovative and distrupted products.

Orion values creating a productive, diverse work environment for employees. We are committed to maintaining a positive work environment where employees value traits that make each one of us different from one another. We all bring a diverse set of perspectives, work and life experiences, and our differences make us more valuable both internally and for our clients.

Growth Potential

Orion is a great place to develop your career, no matter what role you start in. Throughout Europe, most of our roles offer experience in Automotive, Information & Communication Technologies (ICT), Financial Services & FinTech, Healthcare, and Industrial & Consumer Products, so there are multiple industries where you can make an impact.

Education Programs

Orion offers various educational opportunities, including Power BI training with our partner, Microsoft. We also have training programs across Quality Assurance, Software Engineering with languages such as C/C++, Java, Python, PHP, and JavaScript.

Specifically, we offer these training programs, internships and Robotics opportunities through joint programs with universities and engineering colleges.

Employee Benefits
  • Vacation Time
  • Family Benefits
  • Medical Insurance
  • Competitive Salaries
  • Sick Leave
  • Training Programs
  • Flexible Hours
  • Material incentives and assistance; and more.

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