On 08 May 2016, at 05:15, Tim Selander selander@[redacted].attne.jp
[HyperCard] <HyperCard-Mailing-List> wrote:
> have noticed that quite a lot of new software I am interested
> in only runs on the latest OSX. Since through this mailing list,
> I have the "ear" of a real honest-to-god developer, I'm curious
> to know what features (bugs?) the new operating systems gives
> developers that prevents better backward compatibility?
There's no big ones, newer OS versions just have lots of small improvements.. Some just involve Apple providing API to do things you would have had to engineer yourself (like placing additional buttons in a window's title bar), others are whole new views for new list styles (which, again, one could have engineered oneself). I think since 10.7 there have also been big improvements in localization. Given that some of this was four years ago, I'm a bit fuzzy on the details.
In the case of Stacksmith (and probably many smaller software developers' products) it is likely a combination of "it's hard enough to make the program do what I want on this OS, I don't want to test everything I write on three other older OS versions just to see if it's broken now" and the fact that Apple's newest versions of its developer tools (Xcode etc.) tend to cut off older versions eventually. In the case of the latest version, the oldest MacOS X Xcode will let me build for is now 10.4 â€” and I seem to remember that there were some bugs in its support for older OSes (it looks for one particular but very important library in the new location instead of the old) that 10.8 is a more realistic minimum.
Supporting an older OS is hard work. Not only do you need a computer that will still run it, if an issue occurs, you will need to be able to track down its reason, which usually means building the application on that older OS and running it in the debugger there, which in turn means using an older version of Xcode, which means you lose many helpful features that make development faster... And every older OS version you support means you have to verify each feature an extra time on an extra computer.
Now add to that that Stacksmith is a completely new program, still in development. By the time I release a final version, Apple will probably be at 10..13. So I'll try to support the newest, and maybe one back if the newest was quite a while ago, or cost a lot of money, or dropped support for many computers.
Hope that helps explain the rationale a bit.
-- Uli Kustererhttps://stacksmith.org