title: Rails: During asset precompile throws error key must be 16 bytes
body: <p>I am storing my secret key in environment and /config/environments/production.rb has config.require_master_key = true uncommented</p>
  
  <pre><code>config.require_master_key = true
  </code></pre>
  
  <p>When running </p>
  
  <pre><code>RAILS_ENV=production bundle exec rake assets:precompile
  </code></pre>
  
  <p>I get the error</p>
  
  <pre><code>/Users/something/Development/wwwroot/trivial/config/environment.rb:5:in `&lt;main&gt;'
  /Users/something/.rbenv/versions/2.5.1/bin/bundle:23:in `load'
  /Users/something/.rbenv/versions/2.5.1/bin/bundle:23:in `&lt;main&gt;'
  
  Caused by:
  ArgumentError: key must be 16 bytes
  /Users/something/Development/wwwroot/trivial/config/environment.rb:5:in `&lt;main&gt;'
  /Users/something/.rbenv/versions/2.5.1/bin/bundle:23:in `load'
  /Users/something/.rbenv/versions/2.5.1/bin/bundle:23:in `&lt;main&gt;'
  Tasks: TOP =&gt; environment
  </code></pre>
  
  <p>any ideas on how to fix this error? What else can I do?</p>