diff --git a/images/postfix/Dockerfile b/images/postfix/Dockerfile
index 8291e3651f9c1589de1078390aa0ebff63d7dff1..5f4aa49fa63b7fdc764a883e31222b48aa922846 100644
--- a/images/postfix/Dockerfile
+++ b/images/postfix/Dockerfile
@@ -11,8 +11,10 @@ FROM docker.io/library/alpine:3.17.2
 RUN apk add --no-cache ca-certificates rsyslog supervisor
 RUN update-ca-certificates
 
+# renovate: datasource=repology depName=alpine_3_17/postfix versioning=loose
+ENV POSTFIX_VERSION="3.7.4-r0"
 
-RUN apk add --no-cache postfix cyrus-sasl cyrus-sasl-login
+RUN apk add --no-cache postfix=${POSTFIX_VERSION} cyrus-sasl cyrus-sasl-login
 
 RUN mkdir /var/spool/postfix/etc && echo "smtp		25/tcp		mail		# Simple Mail Transfer" > /var/spool/postfix/etc/services
 
diff --git a/renovate.json b/renovate.json
index b7b7c8fca4bb4b1fc77bab2ca7712582ee21d77b..58190e3170942e20c78027ebdafa8cffb6459343 100644
--- a/renovate.json
+++ b/renovate.json
@@ -38,6 +38,13 @@
       ],
       "datasourceTemplate": "docker",
       "versioningTemplate": "docker"
+    },
+    {
+      "fileMatch": ["Dockerfile$"],
+      "matchStrings": [
+        "#\\s*renovate:\\s*datasource=(?<datasource>.*?) depName=(?<depName>.*?)( versioning=(?<versioning>.*?))?\\sENV .*?_VERSION=\"(?<currentValue>.*)\"\\s"
+      ],
+      "versioningTemplate": "{{#if versioning}}{{{versioning}}}{{else}}semver{{/if}}"
     }
   ],
   "packageRules": [