Rspamd supports DKIM signing. Since we also use it for SPAM filtering we can save one running application by using Rspamd also for DKIM. - [x] Change Rspamd [config](https://rspamd.com/doc/modules/dkim_signing.html) - [x] Add ed25519 as additional [signing algorithm](https://tools.ietf.org/id/draft-ietf-dcrup-dkim-crypto-11.html) - [x] Deploy new config - [x] Either update DNS entries or migrate old DKIM keys - [x] [Test](https://www.appmaildev.com/de/dkim) DKIM signing