What is the ruling on working as a computer programmer for a Tunisian company that operates on behalf of a foreign company, if the program's service is to provide consultation to hotels on how to rent out rooms to improve revenues, whether wholesale to another company or to individuals?

It is permissible to design computer programs that offer permissible consultations. Programs that can be used for both lawful and unlawful purposes are permissible to design and sell, except to someone known to be using them for unlawful purposes. Providing consulting services to hotels regarding room rentals is an act that is fundamentally permissible.