《OXO》係喺延遲儲存電子自動計算器(EDSAC) 上面編寫嘅。EDSAC係最早期嘅儲存程序電腦，可以讀取同寫入儲存器。部機有三塊小型顯像管屏幕，用嚟指示儲存器狀態；道格拉斯重新定義咗一塊屏幕，令佢可以向用戶顯示其他信息，例如井字過三關嘅遊戲狀態。遊戲完成目的之後被廢棄，後來又重建翻。
OXO is written on the Delayed Storage Electronic Automatic Calculator (EDSAC). EDSAC was the earliest storage program computer that could read and write to memory. The desktop had three small CRT screens to indicate the status of the memory, and Douglas redefined one screen so that he could display other information to the user, such as the state of the tic-tac-toe game. The game was abandoned after its purpose was completed, and later rebuilt.