Is working in a securities brokerage firm, as an intermediary for buying and selling shares and bonds on the Egyptian Stock Exchange, prohibited, especially in the margin trading department which finances clients with interest?

Dealing with customer financing involving debt in exchange for interest is forbidden by Islamic law (riba), as it is a loan with a condition of increase for the lender, and every loan that brings a benefit is usury (riba). It is not permissible to work in this department because it is assisting in usury. As for working in the company in general, if its activity is based on forbidden transactions, then it is not permissible to work for it at all, even if the work does not directly involve usurious dealings. Otherwise, there is no harm in working in departments that have no relation to forbidden transactions.