How to rebuild Bundle in Capistrano? - ruby-on-rails

Question

I have been working up updating a Rails app that uses Rbenv, Bundler, and Capistrano, and after installing Ruby on the remote server, my deploys consistently fail with the following:
DEBUG [c642111f] rake aborted!
DEBUG [c642111f] LoadError: cannot load such file -- rails/all
DEBUG [c642111f] /home/deploy/domains/myapp/releases/20151019224651/config/application.rb:3:in `require'
DEBUG [c642111f] /home/deploy/domains/myapp/releases/20151019224651/config/application.rb:3:in `<top (required)>'
DEBUG [c642111f] /home/deploy/domains/myapp/releases/20151019224651/Rakefile:4:in `require'
DEBUG [c642111f] /home/deploy/domains/myapp/releases/20151019224651/Rakefile:4:in `<top (required)>'
DEBUG [c642111f] (See full trace by running task with --trace)
(Backtrace restricted to imported tasks)
cap aborted!
SSHKit::Runner::ExecuteError: Exception while executing as deploy#myapp.com: rake exit status: 1
rake stdout: Nothing written
rake stderr: rake aborted!
LoadError: cannot load such file -- rails/all
/home/deploy/domains/myapp/releases/20151019224651/config/application.rb:3:in `require'
/home/deploy/domains/myapp/releases/20151019224651/config/application.rb:3:in `<top (required)>'
/home/deploy/domains/myapp/releases/20151019224651/Rakefile:4:in `require'
/home/deploy/domains/myapp/releases/20151019224651/Rakefile:4:in `<top (required)>'
(See full trace by running task with --trace)
SSHKit::Command::Failed: rake exit status: 1
rake stdout: Nothing written
rake stderr: rake aborted!
LoadError: cannot load such file -- rails/all
/home/deploy/domains/myapp/releases/20151019224651/config/application.rb:3:in `require'
/home/deploy/domains/myapp/releases/20151019224651/config/application.rb:3:in `<top (required)>'
/home/deploy/domains/myapp/releases/20151019224651/Rakefile:4:in `require'
/home/deploy/domains/myapp/releases/20151019224651/Rakefile:4:in `<top (required)>'
(See full trace by running task with --trace)
Tasks: TOP => deploy:assets:precompile
(See full trace by running task with --trace)
The deploy has failed with an error: Exception while executing as deploy#myapp.com: rake exit status: 1
rake stdout: Nothing written
rake stderr: rake aborted!
LoadError: cannot load such file -- rails/all
/home/deploy/domains/myapp/releases/20151019224651/config/application.rb:3:in `require'
/home/deploy/domains/myapp/releases/20151019224651/config/application.rb:3:in `<top (required)>'
/home/deploy/domains/myapp/releases/20151019224651/Rakefile:4:in `require'
/home/deploy/domains/myapp/releases/20151019224651/Rakefile:4:in `<top (required)>'
(See full trace by running task with --trace)
If I ssh in to the remote server and try tasks such as be rails c from the releases/20151019224651 path, I get the same messages.
However, I've noticed that once I run rm -rf .bundle, all problems go away and everything works great.
The problem is that it's too late to fix the aborted deploy, and every successive deploy attempt runs into the same issue.
What might be going on here, and how can I fix it for good?