The codename for Discord during its development was Eris.
Eris is the Greek goddess associated with strife and discord, making the name a fitting early label for a communication project intended to solve “discord” among gamers. The codename was used before the product was publicly released and before the team settled on Discord as the public brand.
Discord grew out of work by Jason Citron and Stanislav Vishnevskiy at Hammer & Chisel. Citron had previously founded OpenFeint, while Hammer & Chisel first worked on the mobile game Fates Forever. During that project, the team found existing voice-chat tools awkward for coordinating games such as League of Legends and Final Fantasy XIV, which prompted them to build a more practical chat service.
Discord launched publicly in May 2015. Eris is sometimes confused with Discord’s later mascot and branding elements, such as Clyde, or with Eris, the separate JavaScript library for Discord bots. Those names are related only by association; the development codename refers to the service before launch.