diff --git a/rowan/components/scripts/deploymentPostLoad.st b/rowan/components/scripts/deploymentPostLoad.st
index 348fd66..aaf19a3 100644
--- a/rowan/components/scripts/deploymentPostLoad.st
+++ b/rowan/components/scripts/deploymentPostLoad.st
@@ -5,7 +5,10 @@ symbolDictionary := Rowan image
 	ifAbsent: [Error signal: 'Kepler symbol dictionary missing' ].
 
 "Global variables definition"
-symbolDictionary at: #SystemInterfaces put: Namespace new.
+symbolDictionary
+	at: #SystemInterfaces
+	ifPresent: [:namespace | namespace ifNil: [symbolDictionary at: #SystemInterfaces put: Namespace new]]
+	ifAbsentPut: [Namespace new "anyway, should never happen because preload script defines it"].
 
 "Register Kepler's built-in system interfaces"
 (OrderedCollection new
diff --git a/rowan/components/scripts/developmentPostLoad.st b/rowan/components/scripts/developmentPostLoad.st
index fb641b7..344cb43 100644
--- a/rowan/components/scripts/developmentPostLoad.st
+++ b/rowan/components/scripts/developmentPostLoad.st
@@ -5,7 +5,10 @@ symbolDictionary := Rowan image
 	ifAbsent: [Error signal: 'Kepler symbol dictionary missing' ].
 
 "Global variables definition"
-symbolDictionary at: #SystemInterfaces put: Namespace new.
+symbolDictionary
+	at: #SystemInterfaces
+	ifPresent: [:namespace | namespace ifNil: [symbolDictionary at: #SystemInterfaces put: Namespace new]]
+	ifAbsentPut: [Namespace new "anyway, should never happen because preload script defines it"].
 
 "Register Kepler's built-in system interfaces"
 (OrderedCollection new