diff --git a/cloudbender/stack.py b/cloudbender/stack.py
index b5b1a25..b514a21 100644
--- a/cloudbender/stack.py
+++ b/cloudbender/stack.py
@@ -1059,11 +1059,18 @@ class Stack(object):
 
             if "parameters" not in settings:
                 settings["parameters"] = {}
+
             # hack for bug above, we support one level of nested values for now
             _val = pulumi_settings["config"]["{}:{}".format(
                 self.parameters["Conglomerate"], key)]
             if '.' in key:
-                (root, leaf) = key.split('.')
+                try:
+                    (root, leaf) = key.split('.')
+                except ValueError as e:
+                    raise ParameterIllegalValue(
+                      "Currently only one level hierachies within parameters are supported!"
+                    )
+
                 if root not in settings["parameters"]:
                     settings["parameters"][root] = {}
 
diff --git a/pyproject.toml b/pyproject.toml
index f994a47..3dd7abe 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -26,6 +26,7 @@ dependencies = [
         "pulumi-aws-native==0.103.0",
         "pulumi-policy==1.11.0",
         "pulumi-command==0.10.0",
+        "pulumi_random==4.16.6",
         ]
 
 classifiers = [