What is the ruling on carrying out engineering works for banks that deal with usury and provide necessary services?

It is not permissible to deal with usurious banks or to provide them with any services, even if these services are non-usurious. This is because the predominant nature of their work is based on usury, and this falls under warring against Allah and His Messenger. A Muslim must fear Allah and keep away from assisting those who are upon falsehood, contenting himself with lawful earnings. For whoever gives up something for the sake of Allah, Allah will compensate him with something better.