Avie Tevanian, Apple’s VP of Software Engineering and one of its top executives, will reportedly be leaving the company, according to the New York Post. Tevanian began work with Apple CEO Steve Jobs back in 1988, as part of NeXT, which was purchased by Apple in 1997, and has played an integral role in the development of Mac OS X. The newspaper cites several possible reasons for his impending departure, including frustration over the performance of Apple’s hardware–which seems unlikely–and his desire to simply do something else. The search for a replacement, says the newspaper, “hasn’t been going very well.”