What is the ruling on working for a company that relies on usurious loans for its projects and employee salaries, knowing that the employee was unaware of this? Is the money he earned from this company considered halal or usurious wealth? Is it permissible for him to continue working there until he finds another job, or must he leave immediately?

If the company's projects are permissible, and the programmer is not directly involved in its accounting, then it is permissible for him to work there, though working with those who engage in usury is disliked (makrooh). The sin of usury falls upon the company and those who directly engage in it or assist with it. The programmer's salary is lawful in exchange for his permissible work. Sheikh Ibn Uthaymeen stated that it is permissible for an employee to work in a company that deals with usury if he does not directly engage in usury through writing, witnessing, or service, and his work is separate from it.