What is the ruling on terminating an employee for working on a program similar to the company's program outside of working hours, and what is the ruling on the employee's action?

Dismissing the partner because he developed a program similar to an existing program in the company depends on the contract between the company and your colleague. If the contract has not expired and its terms have not been violated, then his dismissal is not permissible. However, if he has violated the terms or the contract period has ended, the company may dismiss him. Regarding your colleague developing a similar program without the company's permission, the default is permissibility, unless the company is the original inventor of the program and holds patent rights, or if the program would reveal company secrets or harm the company.