however, most of yellow box and other rhapsody technologies went on to be used in macos's cocoa api. bowing to developers' wishes, apple also ported existing classic mac os technologies into the new operating system and implemented the carbon api to provide classic mac os api compatibility. widely used mac os libraries like quicktime and applescript were ported and made available to developers. carbon allowed developers to maintain full compatibility and native functionality using their current codebases, while enabling them to take advantage of new features at their discretion.