[mook]

Thanks; I'm not sure in that case saying 1.x is guaranteed to not break things is very useful at all. Systemd (as far as I know) follows semantic versioning, but their version number is up in the hundreds. Without some sort of guess at how long a release might last, 2.0 might as well ship the minute after 1.0 ships. (Okay, probably not...)

[tshepang]

The core team has reserved the right to break backcompat without changing the major version if they find a serious problem in 1.x series. So I expect that it will be a while (at least a few years) before 2.0 is created.

[tshepang]

I don't think systemd does follow any semantic versioning: each of the feature releases change the major version.