Sergej started his career as a web developer in 2002. From 2009 to 2011, he was a Project Manager at Bonnier Digital Consumer Services. In 2011, he became the Co-Founder and CTO of Rabble Communications AB, a marketing platform. He is also the Founder of Banterfly and Charismatic Revolution. In 2014 Sergej, became a Digital Currency Specialist at ITG Digital.
Since 2014, Sergej has been the Founder and CEO of Bitrefill.