How long will MacOS Sierra be viable for Scrivener 3?

Since I always upgraded my Mac with the newest OS (after waiting a couple of months for them to sort out all the bugs), I never really paid attention to how long an old OS could keep running the latest patches of Scrivener 2. But, with my Mac approaching near the end of it’s support life with Apple, and the ever-decreasing chance of me purchasing a new Mac, I am now curious about how long your new updates for Scrivener 3 will work for the original OS it was released on (High Sierra).

I know there is no way to answer this question definitively. If Apple performs another mass overhaul like they did when they switched to Intel processors (especially with the rumors they may be going back to manufacturing their own processors), obviously you will develop with current/future OSes in mind. But, barring any major changes that make it impossible (or unreasonably difficult/expensive), what is the “standard” when it comes to ensuring compatibility with previous operating systems?

We’ve always managed a good few years in the past. Scrivener 2 could run on 10.7 (10.6 at a push) as of its later versions, and they were several years old. As you say, I can’t give you a definitive answer, since it will depend on what Apple does. If Apple forces me to rewrite lots of code to work with the latest frameworks, then it will be more difficult to support older frameworks. I’d say that I’d always aim to support at least the past two macOS releases, though.

All the best,
Keith