diff --git a/manifests/service.pp b/manifests/service.pp
index a72575d..78c3fde 100644
--- a/manifests/service.pp
+++ b/manifests/service.pp
@@ -72,41 +72,21 @@
                           $allow_isolate               = undef,
                         ) {
 
-  if($type!=undef and $forking==true)
+  if($type != undef and $forking == true)
   {
     fail('Incompatible options: type / forking')
   }
 
-  if($type != 'oneshot' and is_array($execstart) and count($execstart) > 1)
+  if($type != 'oneshot' and $execstart.is_a(Array) and count($execstart) > 1)
   {
     fail('Incompatible options: There are multiple execstart values and Type is not "oneshot"')
   }
 
-  if($type != 'oneshot' and is_array($execstop) and count($execstop) > 1)
+  if($type != 'oneshot' and $execstop.is_a(Array) and count($execstop) > 1)
   {
     fail('Incompatible options: There are multiple execstop values and Type is not "oneshot"')
   }
 
-  # TODO: puppet4 / puppet 6 compatibility
-  # if(size($unset_env_vars)>0)
-  # {
-  #   if(defined($::eyp_systemd_release))
-  #   {
-  #     $systemd_release=0+$::eyp_systemd_release
-  #
-  #     if($systemd_release < 235)
-  #     {
-  #       fail("ERROR: UnsetEnvironment is not available for systemd < 235 - current release: ${systemd_release}")
-  #     }
-  #   }
-  # }
-
-  # if($restart!=undef)
-  # {
-  #   # Takes one of no, on-success, on-failure, on-abnormal, on-watchdog, on-abort, or always.
-  #   validate_re($restart, [ '^no$', '^on-success$', '^on-failure$', '^on-abnormal$', '^on-watchdog$', '^on-abort$', '^always$'], "Not a supported restart type: ${restart} - Takes one of no, on-success, on-failure, on-abnormal, on-watchdog, on-abort, or always")
-  # }
-
   include ::systemd
 
   concat { "/etc/systemd/system/${servicename}.service":
diff --git a/metadata.json b/metadata.json
index 3da19dd..53a1d96 100644
--- a/metadata.json
+++ b/metadata.json
@@ -58,7 +58,7 @@
   "requirements": [
     {
       "name": "puppet",
-      "version_requirement": ">= 3.8.0"
+      "version_requirement": ">= 4.0.0"
     }
   ]
 }