This API allows you to programmatically initiate a backup of all of your Mercurial repositories.
The URL for the API calls is:
https://secure.devzing.com/api/v1/mercurial/backup?apikey={key}
You can find your key in Settings -> Account info.
Note that these API calls place a request for a backup onto a queue and return immediately. You will receive an email when the backup is complete.
You can also set up a remote backup destination to have the backup copied to your server.