# smtpd -dv -f /etc/mail/smtpd.conf -T rules  
debug: init ssl-tree
info: loading pki information for franziska-kellermann.de
debug: init ca-tree
debug: init ssl-tree
info: loading pki keys for franziska-kellermann.de
info: OpenSMTPD 5.9.1 starting
debug: bounce warning after 4h
debug: using "fs" queue backend
debug: using "ramqueue" scheduler backend
debug: using "ram" stat backend
debug: parent_send_config_ruleset: reloading
debug: parent_send_config: configuring pony process
debug: parent_send_config: configuring ca process
debug: queue: done loading queue into scheduler
filter: building simple chains...
filter: building complex chains...
filter: done building complex chains
debug: ca_engine_init: using RSA privsep engine
debug: init private ssl-tree
debug: smtp: listen on IPv6:2a03:b0c0:3:d0::ad0:8001 port 587 flags 0x469 pki "franziska-kellermann.de" ca ""
debug: smtp: listen on IPv6:fe80::601:20ff:febe:8701%vio0 port 587 flags 0x469 pki "franziska-kellermann.de" ca ""
debug: smtp: listen on 46.101.128.75 port 587 flags 0x469 pki "franziska-kellermann.de" ca ""
debug: smtp: listen on IPv6:2a03:b0c0:3:d0::ad0:8001 port 25 flags 0x401 pki "franziska-kellermann.de" ca ""
debug: smtp: listen on IPv6:fe80::601:20ff:febe:8701%vio0 port 25 flags 0x401 pki "franziska-kellermann.de" ca ""
debug: smtp: listen on 46.101.128.75 port 25 flags 0x401 pki "franziska-kellermann.de" ca ""
debug: smtp: listen on 127.0.0.1 port 25 flags 0x400 pki "" ca ""
debug: smtp: listen on IPv6:fe80::1%lo0 port 25 flags 0x400 pki "" ca ""
debug: smtp: listen on IPv6:::1 port 25 flags 0x400 pki "" ca ""
debug: pony: rsae_init
debug: pony: rsae_init
debug: smtp: will accept at most 486 clients
debug: smtpd: scanning offline queue...
debug: smtpd: offline scanning done
debug: smtp: new client on listener: 0x1bc35b540000
smtp-in: New session 63040c32385d5260 from host franziska-kellermann.de [local]
rule matched: accept from <localhost> for  domain <localnames> alias aliases deliver to lmtp "/var/dovecot/lmtp rcpt-to"
debug: aliases_get: returned 1 aliases
rule matched: accept from <localhost> for  domain <localnames> alias aliases deliver to lmtp "/var/dovecot/lmtp rcpt-to"
debug: aliases_get: returned 1 aliases
rule matched: accept from <localhost> for  domain <localnames> alias aliases deliver to lmtp "/var/dovecot/lmtp rcpt-to"
debug: aliases_get: returned 1 aliases
rule matched: accept from <localhost> for  domain <localnames> alias aliases deliver to lmtp "/var/dovecot/lmtp rcpt-to"
debug: aliases_get: returned 1 aliases
rule matched: accept from <localhost> for  domain <localnames> alias aliases deliver to lmtp "/var/dovecot/lmtp rcpt-to"
debug: aliases_get: returned 1 aliases
smtp-in: Failed command on session 63040c32385d5260: "RCPT TO:<ckeen@franziska-kellermann.de> " => 550 Invalid recipient
smtp-in: Received disconnect from session 63040c32385d5260
debug: smtp: 0x1bc314774000: deleting session: disconnected


smtpd.conf:
# tables
table aliases file:/etc/mail/aliases
table virtuals file:/etc/mail/virtuals
table passwd file:/etc/mail/passwd
table domains file:/etc/mail/domains

# PKI
pki franziska-kellermann.de certificate "/etc/ssl/certs/mail.franziska-kellermann.de.crt"
pki franziska-kellermann.de key "/etc/ssl/private/mail.franziska-kellermann.de.key"

# To accept external mail, replace with: listen on all
#
listen on lo0
listen on egress port 25 tls pki franziska-kellermann.de
listen on egress port 587 tls-require pki franziska-kellermann.de auth <passwd>

accept from local for local alias <aliases> deliver to lmtp "/var/dovecot/lmtp" rcpt-to
accept from any for domain <domains> virtual <virtuals> deliver to lmtp "/var/dovecot/lmtp" rcpt-to
accept from local for any relay

in etc/mail/aliases the following has been added:
vmail: /dev/null
root: ckeen
ckeen: ckeen@franziska-kellermann.de
(afterwards I ran newaliases)

# cat domains                                                                                                                     
franziska-kellermann.de


# cat virtuals                                                     
                                                             
abuse@franziska-kellermann.de ckeen@franziska-kellermann.de
postmaster@franziska-kellermann.de ckeen@franziska-kellermann.de
webmaster@franziska-kellermann.de ckeen@franziska-kellermann.de
ckeen@franziska-kellermann.de vmail
franziska@franziska-kellermann.de vmail
post@franziska-kellermann.de vmail