> But why isn't it backward-compatible? It is, mostly. 1.8->1.9 was famously a big change, but breaking changes since have been comparatively minor. IMX the m

> But why isn't it backward-compatible? It is, mostly. 1.8->1.9 was famously a big change, but breaking changes since have been comparatively minor. IMX the most common cause for gem breakage is simply rot - old gem, maintainer lost interest, a tiny change required (often due to an open-ended dependency on another gem) but there's no one to do it. Unfortunately, adopting an abandoned gem is non-trivial if the original maintainer doesn't respond, and a lot of gems were written in the Rails goldrush but have fallen into abeyance since.