Is it permissible for a programmer to work for a software company specializing in Islamic banks, given the suspicions surrounding the extent of some of these banks' adherence to Sharia, and the possibility of participating in programming usurious transactions or assisting non-Islamic banks?

Doubting the legitimacy of Islamic banking transactions does not mean that working for a company specializing in developing software for these banks is forbidden. This is because a superficial resemblance does not necessitate an identical ruling, and the fundamental differences between Islamic banking transactions and usurious banks have been clarified in matters such as tawarruq, istisna'a, ijara muntahiya bi al-tamleek (leasing ending in ownership), and installment sales.