There was no such thing as software when Colossus was developed. How did they get it to work?

Colossus, developed during World War II to break German codes, operated using complex hardware and circuits rather than software. Its functionality was achieved through intricate designs of relay switches and vacuum tubes, which processed data and executed logical operations. Engineers and mathematicians, including Tommy Flowers, meticulously designed and wired the machine to perform Boolean logic and calculations, allowing it to analyze and decrypt messages efficiently. The results were achieved through careful engineering and manual programming via plugboards, rather than traditional software coding.