diff --git a/manifests/init.pp b/manifests/init.pp
index f0e2a44..19cf69b 100644
--- a/manifests/init.pp
+++ b/manifests/init.pp
@@ -91,7 +91,7 @@ class zaqar(
   $management_store       = 'mongodb',
   $package_name           = $::zaqar::params::package_name,
   $package_ensure         = 'present',
-  $purge_config           = false,
+  Boolean $purge_config   = false,
 ) inherits zaqar::params {
 
   include zaqar::deps
diff --git a/manifests/policy.pp b/manifests/policy.pp
index 2ae26be..fbb5c48 100644
--- a/manifests/policy.pp
+++ b/manifests/policy.pp
@@ -52,7 +52,7 @@ class zaqar::policy (
   $policy_path          = '/etc/zaqar/policy.yaml',
   $policy_default_rule  = $facts['os_service_default'],
   $policy_dirs          = $facts['os_service_default'],
-  $purge_config         = false,
+  Boolean $purge_config = false,
 ) {
 
   include zaqar::deps