title: Programmatic delivery of emails via SendGrid from PHP (bulk emails)
body: <p>We have been using SendGrid for some time for transactional email delivery, however - we are starting to send bulk packages of email at various intervals in an automated manner.</p>
  
  <p>We are trying to find a way to send these bulk emails to sendgrid for delivery instead of our current process (looping over a list of users and sending the email iteratively)</p>
  
  <p><em>Using something other than sendgrid is not an option</em></p>
  
  <p>We need to basically have a way to upload a list of users, replacement values for keywords in the email: %first_name%, %username% etc - in order to send these emails to users.</p>
  
  <p>What would be the best way to accomplish this?</p>