Statuspage.io integrates with New Relic Synthetics by parsing the emails that New Relic sends out when your site goes down or comes back up.
From a very high level, this works as follows:
NOTE: New Relic emails will only trigger component status changes when there are no active incidents open, and will not affect components in the Degraded Performance or Partial Outage state.
Enable the Automate Components add-on and copy the component-specific email address for the component you want to automate. You can do this by following Step 1 and Step 2 of the instructions in the Getting Started Knowledge Base Article.
Log in to your New Relic account and navigate to the Synthetics tab.
Click Create a new Monitor.
Input the information and settings for the new monitor.
Paste the component automation email address into the email address field.
Click Create my monitor.
Now, when the monitor recognizes an issue, it will send an email to the unique component automation email address and set the component to a "Major Outage" state.
Once the monitor recognizes the issue is resolved, it will send a second email and set the component back to "Fully Operational".