Sergey Kalitin@sergey_kalitinPrincipal Software Engineer at QuestRussian FederationFollowAboutCurrent@QSFT BadgesProblem SolvingCPP CertificationsCertificate: Problem Solving (Basic)VerifiedskillWork Experiencesergey_kalitin has not updated employment details yet.Educationsergey_kalitin has not updated education details yet.