diff --git a/roles/apps/defaults/main.yml b/roles/apps/defaults/main.yml
index d6be21b..f6420c6 100644
--- a/roles/apps/defaults/main.yml
+++ b/roles/apps/defaults/main.yml
@@ -65,4 +65,5 @@ apps_vars:
 apps_include: "{{ apps_vars | dict2items | map(attribute='key') | list }}"
 apps_backup: "{{ apps_vars | dict2items | selectattr('value.backup', 'true') | map(attribute='key') | list | intersect(apps_include) }}"
 apps_proxied: "{{ apps_vars | dict2items | selectattr('value.domain', 'defined') | map(attribute='key') | list | intersect(apps_include) }}"
-apps_senders: "{{ apps_vars | dict2items | selectattr('value.sender', 'true') | map(attribute='value.domain') | list }}"
+apps_senders: "{{ apps_vars | dict2items | selectattr('value.sender', 'true') | map(attribute='key') | list | intersect(apps_include) }}"
+apps_sender_domains: "{{ apps_vars | dict2items | selectattr('key', 'in', apps_senders) | map(attribute='value.domain') | list }}"
diff --git a/roles/apps/templates/compose-files/postfix.yml.j2 b/roles/apps/templates/compose-files/postfix.yml.j2
index 4d426d4..0f5c019 100644
--- a/roles/apps/templates/compose-files/postfix.yml.j2
+++ b/roles/apps/templates/compose-files/postfix.yml.j2
@@ -8,9 +8,9 @@ services:
     image: boky/postfix:{{ apps_vars.postfix.version }}
     restart: always
     environment:
-      ALLOWED_SENDER_DOMAINS: "{{ apps_senders | join(' ') }}"
-      HOSTNAME: "{{ apps_vars.postfix.hostname }}"
-      DKIM_AUTOGENERATE: "true"
+      ALLOWED_SENDER_DOMAINS: {{ apps_sender_domains | join(' ') }}
+      HOSTNAME: {{ apps_vars.postfix.hostname }}
+      DKIM_AUTOGENERATE: true
     networks:
       {{ apps_postfix_docker_network }}:
         aliases: