Posted about 3 years ago. Visible to the public.

During deployment: "You are trying to install in deployment mode after changing your Gemfile"

While deploying an Ruby update to an old application these days, we encountered the following misleading error:

*** [err ::] You are trying to install in deployment mode after changing *** [err ::] your Gemfile. Run `bundle install` elsewhere and add the *** [err ::] updated Gemfile.lock to version control. *** [err ::] *** [err ::] You have deleted from the Gemfile: *** [err ::] *

We found out a newer version of bundler runs on the machines to be deployed to (see bundle -v, it was 2.0.1 in our case) while in the Gemfile.lock an old version of bundler is mentioned in the BUNDLED_WITH block:


This broke during deployment while Capistrano tries to run bundle --deployment --quiet --without development test. On our development machines bundle install run successfully.

Fix this by making sure both sides use the same major versions of bundler (preferably 2.x).

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Owner of this card:

Thomas Eisenbarth
Last edit:
about 3 years ago
by Besprechungs-PC
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Posted by Thomas Eisenbarth to makandra dev
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