Answer:
(Fatwa: 420/409=D)
To design and develop such software which are used in financial institutions and such institutions where no interest transaction is carried out, is lawful. If you supply them directly to interest based institutions then it will be helping in sin and thus disallowed. But, if you are not supplying rather your company supplies it then you will be allowed to receive the salary. It is to be noted that you should avoid such acts which amount helping in sin.
Allah (Subhana Wa Ta’ala) knows Best
Darul Ifta,
Darul Uloom Deoband
