title: capistrano 3 error on rake assets precompile
body: <p>i find out for days for this error but really stuck and the error capistrano gave were not rellay clear what's wrong:</p>
  
  <p>when the capistrano run this:</p>
  
  <pre><code>$HOME/.rbenv/bin/rbenv exec bundle exec rake assets:precompile as myapp@myIP
  </code></pre>
  
  <p>it only said: </p>
  
  <pre><code>Caused by:
  SSHKit::Command::Failed: rake exit status: 1
  SSHKit::Runner::ExecuteError: Exception while executing as myapp@myIP: rake exit status: 1
  rake stdout: Nothing written
  rake stderr: Nothing written
  </code></pre>
  
  <p>does anything had this ?</p>
  
  <p>i already put on Capfile
  <code>require 'capistrano/rails'</code></p>
  
  <p>and <code>deploy.rb</code>:</p>
  
  <pre><code>set :conditionally_migrate, true
  set :migration_servers, -&gt; { primary(fetch(:migration_role)) }
  set :rails_assets_groups, :assets
  set :migration_role, :app
  set :assets_prefix, 'prepackaged-assets'
  set :normalize_asset_timestamps, %w{public/images public/javascripts public/stylesheets}
  </code></pre>