What is the ruling on working in a factory that manufactures ATMs without knowing whether the buyers are usurious banks or non-usurious banks, taking into consideration the prevalence of usurious banks in the country, and without directly participating in the manufacturing of the machine?

It is forbidden to manufacture and sell devices used in usurious transactions, based on the Almighty's saying: (And cooperate in righteousness and piety, and do not cooperate in sin and aggression). Manufacturing them for usurious banks is considered cooperation in usury, which carries a severe warning. As for manufacturing them for Islamic banks or for usurious banks that use them for permissible activities such as withdrawals and bill payments, there is no harm in it, as it is not related to usury. When there is doubt about a bank's use of them, one should act upon the prevailing assumption. If the prevailing assumption is that they will be used for forbidden purposes, then they are forbidden. If the prevailing assumption is that they will be used for permissible purposes, then they are permissible.