Peer Richelsen is Co-Founder and Chairman of Cal.com, a German-born entrepreneur and software engineer on a mission to build open scheduling infrastructure for everyone.

Raised on a farm in Germany, Peer taught himself to code as a teen, launched a viral physical product business, and co-founded Mage Market (YC W19), a peer-to-peer trading card marketplace that raised $880K before shutting down during the pandemic.

Peer also founded Lean Hire, a bootstrapped hiring marketplace that was acquired, and served as Head of Product at On Deck, giving him deep product and team-building expertise before launching Cal.com.

At Cal.com, Peer and co-founder Bailey Pumfleet launched the platform as an open-source Calendly alternative that hit Product of the Month on Product Hunt, raised a $7.4M seed round and a $25M Series A led by Seven Seven Six, totaling $32.4M raised.

Cal.com serves over 20,000 customers including enterprise clients like Klarna and Deel, has amassed 40K+ GitHub stars, and is pursuing its bold mission to connect one billion people through calendar scheduling by 2031.