I wrote a json2smtp proxy server that can be self hosted in Go (golang) See here: https://www.c2kb.com/json2smtp https://github.com/caviv/json2smtp The reason why I needed to write an email proxy was because I was called to do some maintenance on an old legacy system. This system was running on Windows Server 2012, with php version 5.5.6 and Apache 2.4. Very old versions of software. The system was sending emails using the php smtp package and old libssl.dll which supports only TLSv1.0. The smtp service they were using (AWS SES Simple Email Service) has recently dropped the support for SMTP connection via TLS version 1.0. Now in order to support TLS v1.2 for emails on smtp I have to upgrade the whole system. Windows version, php version, Apache version and more - this would have taken me a very long time with many obstacles on the way. Amazon support: https://docs.aws. amazon.com/ses/latest/dg/ security-protocols.html The solution I have chosen was to write this ...