Use @AnthonyMastrean's is_admin from issue #5

sudo.ps1

@@ -1,10 +1,7 @@
 if(!$args) { "usage: sudo <cmd...>"; exit 1 }
 
 function is_admin {
-	$id = [security.principal.windowsidentity]::getcurrent()
-	$name = $id.name -replace '^[^\\]*\\', ''
-	$admin_group = (gwmi win32_group -filter "LocalAccount=True AND SID='S-1-5-32-544'").name # be language-agnostic
-	$res = gwmi win32_groupuser | ? { $_.groupcomponent -match "name=`"$admin_group`"" -and $_.partcomponent -match "name=`"$name`"" }
+	$res = net localgroup administrators |? { $_ -match $env:username }
 	if($res) { $true }
 }