diff --git a/modules/caddyhttp/reverseproxy/httptransport.go b/modules/caddyhttp/reverseproxy/httptransport.go
index 9dd7a29a..6f4bd406 100644
--- a/modules/caddyhttp/reverseproxy/httptransport.go
+++ b/modules/caddyhttp/reverseproxy/httptransport.go
@@ -26,6 +26,7 @@ import (
 	"time"
 
 	"github.com/caddyserver/caddy/v2"
+	"golang.org/x/net/http2"
 )
 
 func init() {