We've started working on the module that is, in short, is used for Adding / Searching nodes and users all in one input. Since the module is at beginning, I'd like to better check out possible problems regarding jQuery versioning for this specific module before we dive too deep into jQuery.
We are aware of possible solutions, but we want this module to be contributed to Drupal and we'd like to be able to have this module ready to be used by community out of the box.
Problem is, this is quite feature-rich front-end tool and we'll be having problems with deprecated/removed methods and similar.
There are few roads to take here,
Whether to code this for 1.4.4 version, which is completely possible, but I'm pretty certain that it won't work on high-up versions of jQuery, updated with jQuery update module for instance.
Another option is to use new version of jQuery specifically for this module, if current version on the site is too old to be used with our module. I'm not sure if I want to add another 200+ kb download to the resources, that's why I'm not sure which road to take.
We want this to not be slow(ish) like most of heavy modules on Drupal, so we really want to avoid slowing it down by another resource download or by using old version that's not really optimized well (check performance tests between jQ versions).
We'll also be using Drupal behaviors, attach functions, etc, which is built on top of jQuery (right?), so that's another thing to consider when making this decision.
Since this is going to be quite a long jQuery code, which road would you guys take, sacrifice which part of users? The one using the 1.4.x version or those using > 1.9.x or somehow make it work on both of them? Any suggestions/ideas are appreciated.