Frustrations w/2.3.x and ruby 1.9.(2|3)

Wow, what a clusterf(#$. I am getting ready to write a new app in
3.x so I figured I would upgrade a legacy app to run on 1.9.x to ease
deployment, eliminate proxying requests, gain performance, etc, etc.

What a nightmare.

RubyGems 1.8 throws up all over the screen complaining about it's own
code. The RubyGem poobah apparently thinks this is "a good thing"/
won't fix.
Certain versions of rubygems don't like certain versions of rails.
Rack apparently made a change to set_cookies! which breaks rails
Bundle doesn't like using rails from git, because there are no
etc, etc, etc.

I was hoping to use the latest version of ruby, rack, and rubygems
with a 2.3.x app. Starting to think it's impossible. In order to
use 1.9.3 I think (haven't actually tried this variant yet) I have to
use a downgraded rubygems + 2-3-stable branch from github + stop using
bundle. Maybe.

I liked the whole "convention over configuration" thing, and "it just
works". Not anymore, it looks like i've descended into a
propellerhead's version of DLL hell.

That is all.

I feel your pain. I've been in the midst of similar tasks for a large
2.3.11 codebase. Here are a couple of links that might help:

I'd take it one gem at a time.

Good luck.