Anyways, it would be interesting to pursue a slapd.conf(5)-less
slapd(8). Initially the server would start up without no
configuration, listening only on ldapi:// and running with
access controls allowing only the owner of slapd(8) process
to read/write to the directory (use ldapi:// SASL/EXTERNAL for
authentication). Then, by a series of LDAP add, modify, and
extended operations, the owner could configure the directory
as desired. In general, changes to configuration items would
take effect immediately. So, adding an ACL would change the
policy being enforced.
And to persist the configuration between slapd(8) instances,
the configuration would be written to disk (LDIF) or database
files. While an admin could, in theory, muck with these
files, that practice would be undocumented and unsupported.