Do you know if solargraph requires bundler explicitly, ie: require "bundler"?

One option that hasn't really been explored yet is that since we have all the gems, those could be composed together solely using GEM_PATH and skip bundler entirely at runtime. And if no gem is requiring gem directly, LOAD_PATH could also be used to compose the ruby libraries together.

So, yes, it does explicitly require bundler, but only to use bits of it as a library; it doesn't explicitly run Bundle.setup or require bundler/setup.

I've considered this too for my own bundlerDevEnv tooling: having the two paths by which ruby code can be read (symlinked and canonical) can often confuse ruby into double-loading files, and on top of that, creating the big bag of symlinks is a little expensive for large gemsets. It seems like a slam-dunk for bundlerApp—if not categorically, at least as an option.

I've wondered, too, whether we could get away with providing a completely-fake shim implementation of bundler/setup that would just pass, because we previously put everything on the GEM_PATH.

If there's ever going to be an app that some strategy like this wouldn't work on, it's going to be Shopify's core platform. Maybe I'll give this a shot there when I get a chance.