Happi has been hacking for fun since 1980, and for profit since 1989 when he started his first company. Erik was one of the driving forces behind the High Performance Erlang project (HiPE) from the start in 1996 until he successfully defended his Ph.D dissertation against opponent Simon Peyton-Jones. During his post-doc as a project manager in Martin Odersky’s Scala group he helped in bringing the Scala project to a successful 1.0 release.

As Head of Development, CTO and Chief Scientist at Klarna, one of Sweden's five Unicorns, Erik was responsible for the development and operation of Klarna Online, a system providing creative payment solutions to Internet shops. He also built up the engineering department at Klarna from scratch. Last year Erik released "The BEAM book" his Erlang Runtime System book project on github. Today, Happi is working as CEO for HappiHacking, where most of his time goes into building a new blockchain for Aeternity.