You are wondering if your app will work out if you deploy it to production? Do the following on your local workstation to see if all it works out:

Edit the database.yml and make sure that you have sane credentials for the production blog for your local workstation. Make sure that you also use mysql (not sqlite) locally to see if that works (you might miss a gem or so..).
editor /home/user/fancyproject/config/database.yml

See that the following variables are set to true in config/environments/production.rb:

config.serve_static_assets = true
config.assets.compile = true

If the following commands work, you are most likely good to go. Lets see if we can install all gems correctly:

Check if the rake tasks have errors or if they run through correctly with a clean database:
RAILS_ENV=production bundle exec rake db:drop db:create db:migrate db:seed

Check if you can precompile the assets:
RAILS_ENV=production bundle exec rake assets:precompile

And check if the server throws errors if we run the app in production environment:
RAILS_ENV=production rails s

And watch what is written to your logfile in real time:
tail -f log/production.log