diff --git a/prototype.go b/prototype.go
index 798e012..3692ce3 100644
--- a/prototype.go
+++ b/prototype.go
@@ -3,6 +3,7 @@ package router
 import "io"
 
 type RequestBuilder interface {
+	Prototype() (req PrototypeRequestBuilder)
 	Allowed(method string) (errRes ErrorResponse)
 	Header(header Header) (errRes ErrorResponse)
 	ReadBody(body io.ReadCloser) (errRes ErrorResponse)
@@ -14,6 +15,7 @@ type PrototypeRequestBuilder interface {
 }
 
 type Response interface {
+	Prototype() (req PrototypeResponse)
 	Header() (header Header)
 	BodyBytes() (body []byte)
 }
diff --git a/server.go b/server.go
index 602cf98..57fb453 100644
--- a/server.go
+++ b/server.go
@@ -23,13 +23,19 @@ type server struct {
 	serve     [numStages][]ServeFunc
 }
 
-func NewServer(prototype Prototype, logger log.Logger, serve ServeFunc) (srv *server) {
+func NewServer[RB RequestBuilder, R Response](requestBuilder RB, response R, logger log.Logger, serve func(RB) (R, ErrorResponse)) (srv *server) {
 	srv = &server{
-		prototype: prototype,
-		logger:    logger,
-		serve:     [numStages][]ServeFunc{},
+		prototype: Prototype{
+			PrototypeRequestBuilder: requestBuilder.Prototype(),
+			PrototypeResponse:       response.Prototype(),
+		},
+		logger: logger,
+		serve:  [numStages][]ServeFunc{},
 	}
-	srv.serve[main] = append(srv.serve[main], serve)
+	srv.serve[main] = append(srv.serve[main], func(req RequestBuilder, res Response) (errRes ErrorResponse) {
+		res, errRes = serve(req.(RB))
+		return
+	})
 	return srv
 }