title: Designing application to support config changes without restart
body: <p>What are some ways to design an application such that the configuration can be changed without requiring an application restart?  </p>
  
  <p>One way is to just have a flat file with configs, and then the application reads from the configs whenever it needs a particular value and never store any config values in memory.  </p>
  
  <p>Another option is to allow the application to load the config file once and store values in memory, but then periodically reload the config file in case something changes.</p>