DMARC
A DNS TXT record at _dmarc.yourdomain that tells receiving servers what to do with email that fails SPF and DKIM alignment (nothing, quarantine it or reject it) and where to send reports.
How this affects you
DMARC stops other people sending email that looks like it's from your domain. Email sent through Vaartix passes it, because DKIM signs as your domain. Vaartix suggests a starting record, v=DMARC1; p=none;, and shows whether one is found; it's optional for sending, but Gmail and Yahoo expect bulk senders to have one. Start with p=none, read the reports, then tighten to quarantine and reject.
Learn more
Vaartix is a transactional email API built in India. SPF, DKIM and a return path on your domain are set up for you, and every feature is free during the private beta.