diff --git a/pkg/urlutil/urlutil.go b/pkg/urlutil/urlutil.go
index 272907de0..a8cf7398c 100644
--- a/pkg/urlutil/urlutil.go
+++ b/pkg/urlutil/urlutil.go
@@ -20,7 +20,6 @@ import (
 	"net/url"
 	"path"
 	"path/filepath"
-	"strings"
 )
 
 // URLJoin joins a base URL to one or more path components.
@@ -70,18 +69,5 @@ func ExtractHostname(addr string) (string, error) {
 	if err != nil {
 		return "", err
 	}
-	return stripPort(u.Host), nil
-}
-
-// Backported from Go 1.8 because Circle is still on 1.7
-func stripPort(hostport string) string {
-	colon := strings.IndexByte(hostport, ':')
-	if colon == -1 {
-		return hostport
-	}
-	if i := strings.IndexByte(hostport, ']'); i != -1 {
-		return strings.TrimPrefix(hostport[:i], "[")
-	}
-	return hostport[:colon]
-
+	return u.Hostname(), nil
 }