In 1999, Zachariassen co-founded the security firm Virus112 and served as its CTO.[5] In 2002, he co-founded the antivirus software company BullGuard and served as its CEO until 2008.[6][7]
In 2010, Zachariassen co-founded Vivino with Theis Søndergaard in Copenhagen.[2][8] The company launched a mobile application in 2010 that allows users to scan wine labels to access crowd-sourced ratings and reviews.[8][9] The platform's user base grew from 12,000 in 2011 to over 50 million by 2021. During his tenure, Vivino expanded into an e-commerce marketplace. By 2021, Vivino had raised over $220 million in venture funding, including a Series D round.[10]
In June 2018, Zachariassen stepped down as CEO and transitioned to the roles of board member and Chief Evangelist.[11][12][13] Zachariassen has also created a YouTube series, Raw Startup, which offers advice on entrepreneurship.[14]