Rakuten Viber is one of the most popular and downloaded apps in the world. Working with us provides a unique opportunity to influence hundreds of millions of our users and to be part of the journey that makes us a super-app. Our mission is to make people’s lives easier by enabling meaningful connections, from precious moments with family and friends, through managing business relationships to pursuing their passions.We are a global team of engineers dedicated to creating the best tools to ensure safe, convenient communication for millions of users worldwide. Our culture is built on innovation, teamwork, and a commitment to excellence.We invite the iOS developer to the RTC team. Our cross-platform team develops, analyzes and optimizes Viber calls.Responsibilities:We invite a competent and proactive specialist who knows Swift, Objective-C, C++ that is interested in how the code is executed at the low level. While working with us, he will be engaged in research and development of various aspects of Viber calls on iOS platform:WebRTC library integration and fine-tuningSignaling protocol developmentMedia capturing and processing optimizationCPU/traffic/battery consumption optimizationCalls statistics gathering and analysis.We expect that our candidate knows how to work in a team, carefully thinks out technical solutions, knows how to plan his time, correctly prioritize and needs minimal control.Requirements:Deep knowledge of Swift and Objective-C: OOP, data structures, multithreading, interoperabilityExperience with WebRTC, iOS CallKit and AVAudioSessionUnderstanding how a TCP/IP stack worksIntermediate+ level of English.Advantages:Proficiency in C/C++, Java, Kotlin, JS/TypeScript, Bash, Python.