At Rakuten Viber, we connect people–no matter who they are, or where they are from. As a communication platform that connects hundreds of millions of people around the world, we know that the way people communicate changes on an almost daily basis. That's why we dedicate ourselves to providing added value to communication — from private and group chats to audio and video calls to the ability to follow and contact brands, businesses and celebrities.
Viber is an all-in-one platform for everything communications-based, and all Viber communications are protected by end-to-end encryption.
Viber is part of the Rakuten Group, a world leader in e-commerce and financial services
Back-End Java Developer


  • Participate in the development of a large-scale project
  • Create new features for millions of users
  • Design and write efficient, maintainable code that supports billions of operations per second


  • 5 years of experience in server development
  • Deep knowledge of Java
  • Good understanding of C++ code with the ability to write and debug it
  • Linux and server experience – a must
  • Conversational level of English
  • Excellent oral and written communication skills
  • Higher technical education

Will be a plus:

  • Experience in asynchronous programming and functional programming (e.g. RxJava)
  • Experience in high-load projects (using Akka)
  • Experience with asynchronous network structures such as Netty, Vert.x
  • Knowledge of AWS and its service