Olfactory (2016)

Olfactory is a system that allows users to re-experience memories. Brian is an app programmer who uses the system to relive the beginning of his relationship with his girlfriend, Amanda. Brian, who writes and rewrites code for a living, figures out how to hack the system so he can alter memories, and rewrite memories from his relationship with Amanda. But once he starts messing with the past, his waking life is plagued with visions of his ex-girlfriend, Rachel. The more Brian tinkers with his past, the more his grip on reality begins to slip.