Maddy is fantastic -- for greater flexibility/ease of deployment, you can pre-provision your DKIM keys as well. Maddy also works wonderfully when combined with

Maddy is fantastic -- for greater flexibility/ease of deployment, you can pre-provision your DKIM keys as well. Maddy also works wonderfully when combined with other technologies, it's nice, simple and light. It works great with Haraka[0] on the outside proxying email to maddy instances on the inside. I've also combined it with SES provisioned with Pulumi + k8s[1] (for those on AWS), which is a little bit more involved but is what I use on projects now. Another entry in this space is chasquid[2] but I've only used/can recommend maddy. Maddy is so good it makes me think anyone could run a hard-multitenant email provider with ease (I'm essentially doing that for each of my projects). [0]: https://haraka.github.io https://haraka.github.io [1]: https://www.vadosware.io/post/setting-up-ses-with-pulumi/ https://www.vadosware.io/post/setting-up-ses-with-pulumi/ [2]: https://github.com/albertito/chasquid https://github.com/albertito/chasquid