diff --git a/docker/Dockerfile.go_build b/docker/Dockerfile.go_build
index a80a3cdef..051831dd7 100644
--- a/docker/Dockerfile.go_build
+++ b/docker/Dockerfile.go_build
@@ -89,3 +89,8 @@ WORKDIR /data
 
 # Entrypoint will handle permission fixes and user switching
 ENTRYPOINT ["/entrypoint.sh"]
+# Default to a complete single-process cluster (master+volume+filer+S3+admin)
+# so the image is usable out of the box — including in environments like
+# GitHub Actions service containers that cannot pass arguments to the entrypoint.
+# Override with any other subcommand at `docker run` / compose time.
+CMD ["mini", "-dir=/data"]
diff --git a/docker/Dockerfile.local b/docker/Dockerfile.local
index c37e5f78a..a275cc639 100644
--- a/docker/Dockerfile.local
+++ b/docker/Dockerfile.local
@@ -40,3 +40,8 @@ WORKDIR /data
 
 # Entrypoint will handle permission fixes and user switching
 ENTRYPOINT ["/entrypoint.sh"]
+# Default to a complete single-process cluster (master+volume+filer+S3+admin)
+# so the image is usable out of the box — including in environments like
+# GitHub Actions service containers that cannot pass arguments to the entrypoint.
+# Override with any other subcommand at `docker run` / compose time.
+CMD ["mini", "-dir=/data"]
diff --git a/docker/Dockerfile.rocksdb_large b/docker/Dockerfile.rocksdb_large
index 6013aacf9..0274d2940 100644
--- a/docker/Dockerfile.rocksdb_large
+++ b/docker/Dockerfile.rocksdb_large
@@ -68,3 +68,8 @@ WORKDIR /data
 
 # Entrypoint will handle permission fixes and user switching
 ENTRYPOINT ["/entrypoint.sh"]
+# Default to a complete single-process cluster (master+volume+filer+S3+admin)
+# so the image is usable out of the box — including in environments like
+# GitHub Actions service containers that cannot pass arguments to the entrypoint.
+# Override with any other subcommand at `docker run` / compose time.
+CMD ["mini", "-dir=/data"]
diff --git a/docker/entrypoint.sh b/docker/entrypoint.sh
index 6632f6645..7ce0595ec 100755
--- a/docker/entrypoint.sh
+++ b/docker/entrypoint.sh
@@ -37,17 +37,21 @@ if [ "$(id -u)" = "0" ]; then
 fi
 
 isArgPassed() {
+  # Match both `-flag` and `--flag` (and their `=value` forms): the Go fla9
+  # library accepts both, and users may pick either form on the CLI.
   arg="$1"
   argWithEqualSign="$1="
+  argDouble="-$1"
+  argDoubleWithEqualSign="-$1="
   shift
   while [ $# -gt 0 ]; do
     passedArg="$1"
     shift
     case $passedArg in
-    "$arg")
+    "$arg"|"$argDouble")
       return 0
       ;;
-    "$argWithEqualSign"*)
+    "$argWithEqualSign"*|"$argDoubleWithEqualSign"*)
       return 0
       ;;
     esac
@@ -95,6 +99,15 @@ case "$1" in
   	exec /usr/bin/weed -logtostderr=true server $ARGS $@
   	;;
 
+  'mini')
+  	ARGS="-dir=/data"
+  	if isArgPassed "-dir" "$@"; then
+  	  ARGS=""
+  	fi
+  	shift
+  	exec /usr/bin/weed -logtostderr=true mini $ARGS $@
+  	;;
+
   'filer')
   	ARGS=""
   	shift