While creating a new application in RoR (on cygwin), I was having issue installing ‘pg’ gem. After a little research I found that you need to install pg-client and pg-devel libraries to install ‘pg’ gem. Even after installing both devel and client packages, still I was unable to install. It turns out I need to install with a particular platform:
gem install pg --platform=x86-mingw32
This install the gem but in my application I had to update my Gemfile as below:
gem 'pg', :platforms => 'mingw'
After doing the above steps, I was able to run bundle install successfully.