SendGrid
Email is the backbone of your customer engagement. The Twilio SendGrid Email API is the email service trusted by developers and marketers for time-savings, scalability, and delivery expertise. Our flexible Email API and proprietary Mail Transfer Agent (MTA), intuitive console, powerful features, and email experts make it easy to ensure all your email gets delivered in seconds and without interruption. Monitor engagement data and optimize deliverability with our Deliverability Insights dashboard.
Whether you’re sending 100 emails or 100 billion, SendGrid is built to scale. Integrate with our RESTful APIs and SMTP in minutes, with sample code libraries available in 7 languages, interactive docs, templates, and more.
Learn more
MailerQ
MailerQ is a high-performance on-premise Mail Transfer Agent (MTA) for delivering millions of emails per day. It is built with a strong focus on performance, ease-of-use, and insights. The MTA comes packed with an intuitive Management Console, REST API, and other functionality necessary for every serious sender to retain and improve their sender reputation and deliverability rates. That’s why it's increasingly becoming the preferred solution of choice for senders of all kinds, from Email Service Providers and e-commerce platforms to banks and government institutes. The management console allows for real-time insights in delivery attempts and results, queues, error logs and a lot more per MTA, IP, target and even per customer, campaign or message type. Response patterns allow you to classify bounces, process feedback loops and adapt MTA behavior based on server responses. This will help you maximize your email deliverability and sender reputation.
Learn more
Sendmail
The sendmail Sentrion platform is specifically designed for large, complex environments, but we make a subset of that solution available as an open-source offering. Sentrion is not for everyone, but if you are using open source email for a large complex environment and need an enterprise platform that will enable your messaging roadmap for years to come (virtualization, consolidation, cloud migration, etc.). The Domain Keys Identified Mail (DKIM) Internet standard enables email senders to digitally sign their messages so that receivers can verify that those messages have not been forged. The DKIM sender authentication scheme allows the recipient of a message to confirm a message originated with the sender’s domain and that the message content has not been altered. A cryptography-based solution, DKIM provides businesses an industry-standard method for mitigating email fraud and protecting an organization’s brand and reputation at a relatively low implementation cost.
Learn more
Postfix
What is Postfix? It is Wietse Venema's mail server that started life at IBM research as an alternative to the widely-used Sendmail program. Now at Google, Wietse continues to support Postfix. Postfix runs (or has run) on AIX, BSD, HP-UX, IRIX, LINUX, MacOS X, Solaris, Tru64 UNIX, and other UNIX systems. It requires ANSI C, a POSIX.1 library, and BSD sockets. Postfix attempts to be fast, easy to administer, and secure. The outside has a definite Sendmail-ish flavor, but the inside is completely different. Multiple SMTP deliveries over the same TLS-encrypted connection. This reuses the existing tlsproxy(8) and scache(8) services. MySQL stored procedure support. Gradual degradation: in many cases a Postfix daemon will log a warning and continue providing the services that are still available, instead of immediately terminating with a fatal error. Postfix can set the execute bit on a queue file. If this does not work, then no mail will ever be delivered.
Learn more