The idea behind BackupCam is to keep a continuous, rolling video of the last few minutes of activity on your mac, in just the same way as dash cams in cars work.
There’s a couple of scenarios where this might be useful. If you’re working on a project where ‘undo’ doesn’t always work reliably or when you most need it to – Xcode, for example, can often let you get your project in a mess without offering you a clear path as to how you got there or how to get back, short of discarding all changes in a particular file – with BackupCam you’ll be able to see exactly how you got to where you are.
Similarly, BackupCam can also help you to review changes that you may not have noticed at the time – perhaps if you were distracted by something else happening, either on screen or off. This can help both as a security and a troubleshooting tool
BackupCam can record up to the previous 30 minutes activity, so may help you recover something that is missed even by Time Machine or other traditional file backup mechanism.
More details are over on the BackupCam webpage, but I’ll just note here that BackupCam can also be controlled by AppleScript, with all the flexibility that that offers. Here’s a sample script that checks whether the last recording was longer ago than the time interval set in BackupCam. If it is, it kicks off a new recording session:
BackupCam is still in the early stages of development (we’re calling v1 a beta), so please feel free to report any bugs or enhancments you’d like to see. At the moment, it requires 10.11.6 or higher and only records the main display. I plan to add support for multiple displays in a future update.