diff --git a/kscr-core/RuntimeBase.cs b/kscr-core/RuntimeBase.cs
index be24b05..d588e28 100644
--- a/kscr-core/RuntimeBase.cs
+++ b/kscr-core/RuntimeBase.cs
@@ -309,6 +309,8 @@ public Stack Execute(string? mainClassName = null)
             else if (name.EndsWith("double>"))
                 return Class.NumericDoubleType;
             else return Class.NumericType.DefaultInstance;
+        if (name == "bool")
+            return Class.BoolType;
         if (name == "byte")
             return Class.NumericByteType;
         if (name == "short")