diff --git a/lib/Hyperlink-Redirect/Helpers.rakumod b/lib/Hyperlink-Redirect/Helpers.rakumod
index a835b8f..f393233 100644
--- a/lib/Hyperlink-Redirect/Helpers.rakumod
+++ b/lib/Hyperlink-Redirect/Helpers.rakumod
@@ -3,7 +3,7 @@ use Libarchive::Filter :gzip;
 
 my $starts-with-protocol = rx:i/ ^https? '://'/;
 
-sub fix-protocol($url) is export {
+sub fix-protocol(Str $url) is export {
     return "http://" ~ $url unless $url ~~ $starts-with-protocol;
 
     return $url;
diff --git a/t/01-basic.rakutest b/t/01-basic.rakutest
index ac6b24f..8a98458 100644
--- a/t/01-basic.rakutest
+++ b/t/01-basic.rakutest
@@ -1,8 +1,17 @@
 use v6.d;
 use Humming-Bird::Core;
-
+use Test;
 # Local libs
 use lib 'lib';
 use Hyperlink-Redirect;
+use Hyperlink-Redirect::Helpers;
 
+plan 2;
 
+ok fix-protocol("seriousbusiness.international") eq  "http://seriousbusiness.international", \
+"fix-protocol fixes bare domains correctly"\
+or diag "\nfix-protocol should return the same string with 'http://' prefixed if protocol isn't specified";
+
+ok fix-protocol("https://www.seriousbusiness.international") eq "https://www.seriousbusiness.international",\
+"fix-protocol does not mangle correctly formatted domains"\
+or diag "\nThe URL should remain unchanged when the protocol is specified";
\ No newline at end of file