diff --git a/.templates/ha_entrypoint.sh b/.templates/ha_entrypoint.sh
index 0260d0149..2dc14b5a9 100755
--- a/.templates/ha_entrypoint.sh
+++ b/.templates/ha_entrypoint.sh
@@ -32,8 +32,14 @@ for SCRIPTS in /etc/cont-init.d/*; do
     fi
 
     # Start the script
-    # shellcheck source=/dev/null
-    source "$SCRIPTS" || echo -e "\033[0;31mError\033[0m : $SCRIPTS exiting $?"
+    if command -v "source" &>/dev/null; then
+        # Use source to share env variables
+        # shellcheck source=/dev/null
+        source "$SCRIPTS" || echo -e "\033[0;31mError\033[0m : $SCRIPTS exiting $?"
+    else
+        # Support for posix only shell
+        /."$SCRIPTS" || echo -e "\033[0;31mError\033[0m : $SCRIPTS exiting $?"
+    fi
 
     # Cleanup
     rm "$SCRIPTS"