title: Event sourcing - event replaying
body: <p>I have been reading about the Event Sourcing pattern which can be very useful if you would like to rebuild your system.</p>
  
  <p>However, what if I need to run the event rebuild while servicing new incoming requests? Is there any particular pattern or best practise for that scenario?</p>
  
  <p>So, instead of scheduling a system downtime, how do I ensure that the new incoming requests will not screw up my system while it is replaying because Event synchronisation and sequence is really important for my system. It involves updating the DB records which are dependent on the event sequence.</p>
  
  <p>Any thoughts?</p>