diff --git a/manifests/init.pp b/manifests/init.pp
index 31c2552a..a61a6d0d 100644
--- a/manifests/init.pp
+++ b/manifests/init.pp
@@ -14,8 +14,8 @@
 #   Defaults to false.
 #
 class barbican(
-  $package_ensure = 'present',
-  $purge_config   = false,
+  $package_ensure       = 'present',
+  Boolean $purge_config = false,
 ) {
 
   include barbican::deps
diff --git a/manifests/policy.pp b/manifests/policy.pp
index 913981be..65f907db 100644
--- a/manifests/policy.pp
+++ b/manifests/policy.pp
@@ -52,7 +52,7 @@ class barbican::policy (
   $policy_path          = '/etc/barbican/policy.yaml',
   $policy_default_rule  = $facts['os_service_default'],
   $policy_dirs          = $facts['os_service_default'],
-  $purge_config         = false,
+  Boolean $purge_config = false,
 ) {
 
   include barbican::deps