diff --git a/templates/start.d/setup_main b/templates/start.d/setup_main
index abac0b0..01fc04a 100644
--- a/templates/start.d/setup_main
+++ b/templates/start.d/setup_main
@@ -1,95 +1,68 @@
 #!/bin/bash
 set -e
 
+# Managing main.cf:
+#     postconf [-dfhHnopvx] [-c config_dir] [-C class,...] [parameter ...]
+#     postconf [-epv] [-c config_dir] parameter=value ...
+#     postconf -# [-pv] [-c config_dir] parameter ...
+#     postconf -X [-pv] [-c config_dir] parameter ...
+
+# Managing master.cf service entries:
+#     postconf -M [-fovx] [-c config_dir] [service[/type] ...]
+#     postconf -M [-ev] [-c config_dir] service/type=value ...
+#     postconf -M# [-v] [-c config_dir] service/type ...
+#     postconf -MX [-v] [-c config_dir] service/type ...
+
+# Managing master.cf service fields:
+#     postconf -F [-fhHovx] [-c config_dir] [service[/type[/field]] ...]
+#     postconf -F [-ev] [-c config_dir] service/type/field=value ...
+
+# Managing master.cf service parameters:
+#     postconf -P [-fhHovx] [-c config_dir] [service[/type[/parameter]] ...]
+#     postconf -P [-ev] [-c config_dir] service/type/parameter=value ...
+#     postconf -PX [-v] [-c config_dir] service/type/parameter ...
+
+# Managing bounce message templates:
+#     postconf -b [-v] [-c config_dir] [template_file]
+#     postconf -t [-v] [-c config_dir] [template_file]
+
+# Managing TLS features:
+#     postconf -T mode [-v] [-c config_dir]
+
+# Managing other configuration:
+#     postconf -a|-A|-l|-m [-v] [-c config_dir]
+
 postconf maillog_file=/dev/stdout
 postconf alias_maps=hash:/etc/aliases
-{{- if getenv "BIFF" }}
-postconf biff='{{ getenv "BIFF" }}'
-{{- end }}
-{{- if getenv "MESSAGE_SIZE_LIMIT" }}
-postconf message_size_limit='{{ getenv "MESSAGE_SIZE_LIMIT" }}'
-{{- end }}
-{{- if getenv "MYDESTINATION" }}
-postconf mydestination='{{ getenv "MYDESTINATION" }}'
-{{- end }}
-{{- if getenv "MYDOMAIN" }}
-postconf mydomain='{{ getenv "MYDOMAIN" }}'
-{{- end }}
-{{- if getenv "MYHOSTNAME" }}
-postconf myhostname='{{ getenv "MYHOSTNAME" }}'
-{{- end }}
-{{- if getenv "MYNETWORKS" }}
-postconf mynetworks='{{ getenv "MYNETWORKS" }}'
-{{- end }}
-{{- if getenv "MYNETWORKS_STYLE" }}
-postconf mynetworks_style='{{ getenv "MYNETWORKS_STYLE" }}'
-{{- end }}
-{{- if getenv "PROPAGATE_UNMATCHED_EXTENSIONS" }}
-postconf propagate_unmatched_extensions='{{ getenv "PROPAGATE_UNMATCHED_EXTENSIONS" }}'
-{{- end }}
-{{- if getenv "RECIPIENT_DELIMITER" }}
-postconf recipient_delimiter='{{ getenv "RECIPIENT_DELIMITER" }}'
-{{- end }}
-{{- if getenv "SMTP_TLS_SECURITY_LEVEL" }}
-postconf smtp_tls_security_level='{{ getenv "SMTP_TLS_SECURITY_LEVEL" }}'
-{{- end }}
-{{- if getenv "SMTPD_CLIENT_RESTRICTIONS" }}
-postconf smtpd_client_restrictions='{{ getenv "SMTPD_CLIENT_RESTRICTIONS" }}'
-{{- end }}
-{{- if getenv "SMTPD_DATA_RESTRICTIONS" }}
-postconf smtpd_data_restrictions='{{ getenv "SMTPD_DATA_RESTRICTIONS" }}'
-{{- end }}
-{{- if getenv "SMTPD_HELO_REQUIRED" }}
-postconf smtpd_helo_required='{{ getenv "SMTPD_HELO_REQUIRED" }}'
-{{- end }}
-{{- if getenv "SMTPD_HELO_RESTRICTIONS" }}
-postconf smtpd_helo_restrictions='{{ getenv "SMTPD_HELO_RESTRICTIONS" }}'
-{{- end }}
-{{- if getenv "SMTPD_RECIPIENT_RESTRICTIONS" }}
-postconf smtpd_recipient_restrictions='{{ getenv "SMTPD_RECIPIENT_RESTRICTIONS" }}'
-{{- end }}
-{{- if getenv "SMTPD_RELAY_RESTRICTIONS" }}
-postconf smtpd_relay_restrictions='{{ getenv "SMTPD_RELAY_RESTRICTIONS" }}'
-{{- end }}
-{{- if getenv "SMTPD_SASL_AUTH_ENABLE" }}
-postconf smtpd_sasl_auth_enable='{{ getenv "SMTPD_SASL_AUTH_ENABLE" }}'
-{{- end }}
-{{- if getenv "SMTPD_SASL_PATH" }}
-postconf smtpd_sasl_path='{{ getenv "SMTPD_SASL_PATH" }}'
-{{- end }}
-{{- if getenv "SMTPD_SASL_TYPE" }}
-postconf smtpd_sasl_type='{{ getenv "SMTPD_SASL_TYPE" }}'
-{{- end }}
-{{- if getenv "SMTPD_TLS_AUTH_ONLY" }}
-postconf smtpd_tls_auth_only='{{ getenv "SMTPD_TLS_AUTH_ONLY" }}'
-{{- end }}
-{{- if getenv "SMTPD_TLS_CERT_FILE" }}
-postconf smtpd_tls_cert_file='{{ getenv "SMTPD_TLS_CERT_FILE" }}'
-{{- end }}
-{{- if getenv "SMTPD_TLS_KEY_FILE" }}
-postconf smtpd_tls_key_file='{{ getenv "SMTPD_TLS_KEY_FILE" }}'
-{{- end }}
-{{- if getenv "SMTPD_TLS_SECURITY_LEVEL" }}
-postconf smtpd_tls_security_level='{{ getenv "SMTPD_TLS_SECURITY_LEVEL" }}'
-{{- end }}
-{{- if getenv "SMTPD_TLS_SESSION_CACHE_DATABASE" }}
-postconf smtpd_tls_session_cache_database='{{ getenv "SMTPD_TLS_SESSION_CACHE_DATABASE" }}'
-{{- end }}
-{{- if getenv "SMTPUTF8_ENABLE" }}
-postconf smtputf8_enable='{{ getenv "SMTPUTF8_ENABLE" }}'
-{{- end }}
-{{- if getenv "VIRTUAL_ALIAS_MAPS" }}
-postconf virtual_alias_maps='{{ getenv "VIRTUAL_ALIAS_MAPS" }}'
-{{- end }}
-{{- if getenv "VIRTUAL_MAILBOX_DOMAINS" }}
-postconf virtual_mailbox_domains='{{ getenv "VIRTUAL_MAILBOX_DOMAINS" }}'
-{{- end }}
-{{- if getenv "VIRTUAL_MAILBOX_MAPS" }}
-postconf virtual_mailbox_maps='{{ getenv "VIRTUAL_MAILBOX_MAPS" }}'
-{{- end }}
-{{- if getenv "VIRTUAL_TRANSPORT" }}
-postconf virtual_transport='{{ getenv "VIRTUAL_TRANSPORT" }}'
-{{- end }}
+{{ with getenv "BIFF" }}postconf biff='{{.}}'{{ end }}
+{{ with getenv "MESSAGE_SIZE_LIMIT" }}postconf message_size_limit='{{.}}'{{ end }}
+{{ with getenv "MYDESTINATION" }}postconf mydestination='{{.}}'{{ end }}
+{{ with getenv "MYDOMAIN" }}postconf mydomain='{{.}}'{{ end }}
+{{ with getenv "MYHOSTNAME" }}postconf myhostname='{{.}}'{{ end }}
+{{ with getenv "MYNETWORKS" }}postconf mynetworks='{{.}}'{{ end }}
+{{ with getenv "MYNETWORKS_STYLE" }}postconf mynetworks_style='{{.}}'{{ end }}
+{{ with getenv "PROPAGATE_UNMATCHED_EXTENSIONS" }}postconf propagate_unmatched_extensions='{{.}}'{{ end }}
+{{ with getenv "RECIPIENT_DELIMITER" }}postconf recipient_delimiter='{{.}}'{{ end }}
+{{ with getenv "SMTP_TLS_SECURITY_LEVEL" }}postconf smtp_tls_security_level='{{.}}'{{ end }}
+{{ with getenv "SMTPD_CLIENT_RESTRICTIONS" }}postconf smtpd_client_restrictions='{{.}}'{{ end }}
+{{ with getenv "SMTPD_DATA_RESTRICTIONS" }}postconf smtpd_data_restrictions='{{.}}'{{ end }}
+{{ with getenv "SMTPD_HELO_REQUIRED" }}postconf smtpd_helo_required='{{.}}'{{ end }}
+{{ with getenv "SMTPD_HELO_RESTRICTIONS" }}postconf smtpd_helo_restrictions='{{.}}'{{ end }}
+{{ with getenv "SMTPD_RECIPIENT_RESTRICTIONS" }}postconf smtpd_recipient_restrictions='{{.}}'{{ end }}
+{{ with getenv "SMTPD_RELAY_RESTRICTIONS" }}postconf smtpd_relay_restrictions='{{.}}'{{ end }}
+{{ with getenv "SMTPD_SASL_AUTH_ENABLE" }}postconf smtpd_sasl_auth_enable='{{.}}'{{ end }}
+{{ with getenv "SMTPD_SASL_PATH" }}postconf smtpd_sasl_path='{{.}}'{{ end }}
+{{ with getenv "SMTPD_SASL_TYPE" }}postconf smtpd_sasl_type='{{.}}'{{ end }}
+{{ with getenv "SMTPD_TLS_AUTH_ONLY" }}postconf smtpd_tls_auth_only='{{.}}'{{ end }}
+{{ with getenv "SMTPD_TLS_CERT_FILE" }}postconf smtpd_tls_cert_file='{{.}}'{{ end }}
+{{ with getenv "SMTPD_TLS_KEY_FILE" }}postconf smtpd_tls_key_file='{{.}}'{{ end }}
+{{ with getenv "SMTPD_TLS_SECURITY_LEVEL" }}postconf smtpd_tls_security_level='{{.}}'{{ end }}
+{{ with getenv "SMTPD_TLS_SESSION_CACHE_DATABASE" }}postconf smtpd_tls_session_cache_database='{{.}}'{{ end }}
+{{ with getenv "SMTPUTF8_ENABLE" }}postconf smtputf8_enable='{{.}}'{{ end }}
+{{ with getenv "VIRTUAL_ALIAS_MAPS" }}postconf virtual_alias_maps='{{.}}'{{ end }}
+{{ with getenv "VIRTUAL_MAILBOX_DOMAINS" }}postconf virtual_mailbox_domains='{{.}}'{{ end }}
+{{ with getenv "VIRTUAL_MAILBOX_MAPS" }}postconf virtual_mailbox_maps='{{.}}'{{ end }}
+{{ with getenv "VIRTUAL_TRANSPORT" }}postconf virtual_transport='{{.}}'{{ end }}
 
 postconf -M spamfilter/unix | grep -q spamfilter || {
     postconf -M spamfilter/unix="spamfilter unix - n n - - pipe"