Erlang

Jan Koum describes how his experience growing up in Ukraine and working at Yahoo shaped WhatsApp’s focus on simple, reliable communication. He explains how WhatsApp began as a status app, pivoted to messaging, and used phone numbers, address books, paid access, and Erlang to build and scale the product. Jim Goetz discusses Sequoia’s investment and the founders’ unusual focus on customers and product over publicity, fundraising, and conventional startup roles. Koum and Goetz also describe WhatsApp’s cultural fit with Facebook and its continuing goal of connecting people around the world.