title: How to evolve akka-persistence events in production?
body: <p>Let's say we have design our system using akka-persistence. Now, we have events stored in the event-store. While, the system in production, a new feature was requested. As a result, we find the best way to go about it is to add or modify a field in an event. Let's say by changing the field name or type.</p>
  
  <p>Now, we have two versions of the event, the one we have in production, and the one in the new deployment, which are not compatible. We will fail if we try to recover data from the old version.</p>
  
  <p>What is the best way to go about that, other than data migration?</p>