自建邮局系统

mailcow，感觉还可以，供您参考：https://www.xiaoz.me/archives/17664

https://mailinabox.email/
有点重量级,不过胜在稳定易用

容器化(Docker)部署poste.io私有邮局
https://ansheng.me/post/container-docker-deploy-poste-io-private-post-office

Mailu.io
https://www.moec.top/archives/1398
或者用Hestia

iRedMail
https://cnfei.cn/index.php/archives/112

Poste 邮件服务基于 Docker 搭建