Do you install wkhtmltopdf separately or allow your gem file to install it?
I'd do the following:
gem 'wicked_pdf', '~> 0.9.10'
gem 'wkhtmltopdf-binary', '~> 0.9.9'
and then set the config:
WickedPdf.config = {
exe_path: "#{ENV['GEM_HOME']}/gems/wkhtmltopdf-binary-#{Gem.loaded_specs['wkhtmltopdf-binary'].version}/bin/wkhtmltopdf_linux_386"
}
This bit #{Gem.loaded_specs['wkhtmltopdf-binary'].version}
queries your gems to find the current version if you were to ever change the version of the gem, your prod server would still be able to find the proper folder.