What is the jurisprudential ruling on working for a software company that operates in the non-banking financial services sector, specifically on the following projects: installments with or without interest, financial leasing where the rent may change with the change in interest rate, and financing small and medium-sized enterprises by deducting a commission in advance and late payment penalties without interest?

Working on this project is not free of Sharia-related concerns, based on what you have described. In the first model, there are sometimes profits on financing, and in the third, fines are imposed for delays and fees are charged upon payment, which may constitute usury (riba).

As for the second model, the possibility of a change in the rental value due to the central bank is permissible if agreed upon in the contract, and the rent amount is known at the beginning of each period. Linking the change to the interest rate, according to the resolution of the Islamic Fiqh Academy and Sharia standards, which permits the standard linkage of long-term wages and rents to a specific index, provided that the rent amount is known at the beginning of each period.

In any case, it is not permissible for you to work in anything that is forbidden or to assist in it. If you find a permissible area in which you can avoid Sharia-related concerns within the company and its services, then there is no harm in working there; otherwise, do not.