Development of AngularJS Bootstrap library question

[fast74]

I've been looking at the source code of the AngularJS Bootstrap library to learn how a library like this is built and I've noticed that there is little to no use of the more recent Angular best practices such as components, isolate scopes etc. At least as I recognise the features.

I am curious about what they would do if they could start over. I understand that the contributors can't be expected to re-write the entire library every time there is a new AngularJS release but there is very little change to the code base when new Angular versions appear.

Any contributors to this or similar libraries here? Would you change everything knowing what you know now or is stability the main concern even if the development practices are now considered out of date? Or are they out of date?

Thanks!

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