Put these files in *config/*.

deploy.rb

require 'mina/git'
require 'mina/rbenv'
require 'mina-contrib/rbenv'
require 'mina-contrib/config'
require 'mina-contrib/bundler'
require 'mina-contrib/safety-check'
require 'mina-contrib/nginx'
require 'mina-contrib/puma'

set :term_mode, :pretty
set :application, :'your-app'
set :environment, :production
set :domain, 'your-server'
set :branch, :master
set :user, 'deploy-user'
set :deploy_to, lambda { "/home/deploy-user/apps/#{application}" }
set :nginx_upstream, lambda { puma_socket }
set :application_domain_names, 'your-app.com'
set :repository, 'git@your-server:your-app-repo.git'
set :shared_paths, ['config/puma.rb', 'config/nginx.conf', 'tmp/puma', 'log']
set :keep_releases, 3
set :config_tasks, [:'puma:config', :'nginx:config']

task :load_environment do
  invoke :'rbenv:load'
end

desc 'Deploys the current version to the server'
task :deploy => :load_environment do
  deploy do
    invoke :'git:clone'
    invoke :'bundler:install'
    invoke :'deploy:link_shared_paths'
    invoke :'deploy:cleanup'

    to :launch do
      invoke :'puma:restart'
    end
  end
end

desc 'Creates an instance of this master api server'
task :create => :load_environment do
  invoke :'deploy:safety_check'
  invoke :setup

  deploy do
    invoke :'git:clone'
    invoke :'bundler:install'
    invoke :'deploy:link_shared_paths'

    to :launch do
      invoke :'config:all'
      # # The folders need to exist for puma to be configured 
      invoke :'puma:config'
      invoke :'nginx:reload'
      invoke :'puma:start'
    end
  end
end

desc 'Destroys the instance'
task :destroy do
  queue %{echo "-----> Destroying the app"}
  # invoke :'monit:destroy'
  invoke :'puma:destroy'
  invoke :'nginx:destroy'

  queue %{
    echo "-----> Removing the app's directory"
    #{echo_cmd "rm -rf #{deploy_to}"}
  }
end

nginx.conf.erb

upstream <%= nginx_site %> {
  server <%= nginx_upstream %>;
}

server {
  listen 80;
  server_name <%= application_domain_names %>;

  keepalive_timeout 5;

  root <%= deploy_to %>/current/public;
  access_log <%= "#{deploy_to}/#{shared_path}/log/nginx.access.log" %>;
  error_log <%= "#{deploy_to}/#{shared_path}/log/nginx.error.log" %>;

  location ^~ /(javascripts|stylesheets)/(.+) {
    deny all;
  }

  location / {
    if ($http_user_agent ~ "MSIE 6.0" ) {
      root <%= deploy_to %>/current/ancient-browser;
    }
    if ($http_user_agent ~ "MSIE 7.0" ) {
      root <%= deploy_to %>/current/ancient-browser;
    }
    if ($http_user_agent ~ "MSIE 8.0" ) {
      root <%= deploy_to %>/current/ancient-browser;
    }
    try_files /system/maintenance.html $uri $uri/index.html $uri.html @app;
  }

  location @app {
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header Host $http_host;
    proxy_pass http://<%= nginx_site %>;
  }
}

puma.rb.erb

environment "<%= environment %>"
threads <%= puma_min_threads %>,<%= puma_max_threads %>
bind "<%= puma_socket %>"
pidfile "<%= puma_pid %>"
state_path "<%= puma_state %>"
<%= "activate_control_app" if puma_activate_control_app %>
<% if puma_on_restart %>
on_restart do
  <%= puma_on_restart %>
end
<% end %>