Index: doc/example-config/conf.d/10-mail.conf
--- doc/example-config/conf.d/10-mail.conf.orig	Mon Jun 18 14:15:32 2018
+++ doc/example-config/conf.d/10-mail.conf	Sun Oct 21 15:56:45 2018
@@ -147,8 +147,9 @@ namespace inbox {
 ##
 
 # Don't use mmap() at all. This is required if you store indexes to shared
-# filesystems (NFS or clustered filesystem).
-#mmap_disable = no
+# filesystems (NFS or clustered filesystem) or for some operating systems
+# which use a separate cache for mmap, such as OpenBSD.
+mmap_disable = yes
 
 # Rely on O_EXCL to work when creating dotlock files. NFS supports O_EXCL
 # since version 3, so this should be safe to use nowadays by default.
@@ -175,7 +176,7 @@ namespace inbox {
 # to make sure that users can't log in as daemons or other system users.
 # Note that denying root logins is hardcoded to dovecot binary and can't
 # be done even if first_valid_uid is set to 0.
-#first_valid_uid = 500
+first_valid_uid = 1000
 #last_valid_uid = 0
 
 # Valid GID range for users, defaults to non-root/wheel. Users having
@@ -208,10 +209,10 @@ namespace inbox {
 
 # UNIX socket path to master authentication server to find users.
 # This is used by imap (for shared users) and lda.
-#auth_socket_path = /var/run/dovecot/auth-userdb
+#auth_socket_path = /var/dovecot/auth-userdb
 
 # Directory where to look up mail plugins.
-#mail_plugin_dir = /usr/lib/dovecot
+mail_plugin_dir = ${PREFIX}/lib/dovecot
 
 # Space separated list of plugins to load for all services. Plugins specific to
 # IMAP, LDA, etc. are added to this list in their own .conf files.
@@ -321,7 +322,7 @@ protocol !indexer-worker {
 # locking methods as well. Some operating systems don't allow using some of
 # them simultaneously.
 #mbox_read_locks = fcntl
-#mbox_write_locks = dotlock fcntl
+mbox_write_locks = fcntl
 
 # Maximum time to wait for lock (all of them) before aborting.
 #mbox_lock_timeout = 5 mins
