Bundler can't find win32-service gem even thought it appears in gem list

I'm trying to use bundler in a 2.3.4 Rails app and am having problems with the win32-service gem. The gem was installed by issuing gem install win32-service --platform mswin32. I installed it outside of bundler as bundler always tries to compile from source which fails miserably.

Output of gem list

win32-service (0.7.1 x86-mswin32-60)

Output of bundle install

Your Gemfile doesn't have any sources. You can add one with a line like 'source :gemcutter'
Could not find gem 'win32-service (>= 0, runtime)' in any of the gem sources.  

I tried using source :gemcutter but as noted above bundler tries to use the source package that does not build.

I have also tried using older versions of the gem (0.5.1) and ha开发者_开发百科d the same problem.

Any ideas?

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Add source :rubygems to the top of your Gemfile.