Please provide the following output:

• dpkg -l bundler ruby
• bundle -v
• gem -v
• bundle env
• gem list

Konstantin Manna wrote:

• bundle -v

Bundler version 1.1.4

This is correct, it's the standard Debian 7 version.

• gem -v

2.4.5

This is non-standard, it looks like you might have run "gem update --system" or similar. It should be version 1.8.23.

The error is because the version of Bundler is too old to work with the very new rubygems version.

I don't know if it's possible to downgrade it again, but if not, you may need to also install a newer version of bundler locally. This isn't intended to be supported with our packages, I don't know if you'll have further issues - we only intend to support stock configurations.

Here is the output on my VM for the same packages, which indicates you have a local difference.

root@foremandeb:~# bundle -v
Bundler version 1.1.4
root@foremandeb:~# gem -v
1.8.23
root@foremandeb:~# dpkg -l bundler ruby
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name                         Version             Architecture        Description
+++-============================-===================-===================-=============================================================
ii  bundler                      1.1.4-6             all                 Manage Ruby application dependencies
ii  ruby                         1:1.9.3             all                 Interpreter of object-oriented scripting language Ruby (defau