diff --git a/cmd/testapi/main.go b/cmd/testapi/main.go
index a7f89c0..a832b26 100644
--- a/cmd/testapi/main.go
+++ b/cmd/testapi/main.go
@@ -124,6 +124,11 @@ func (s *S) injectContext(w http.ResponseWriter, r *http.Request) error {
 	return nil
 }
 
+func (s *S) Session(ctx context.Context) Session {
+	v, _ := ctx.Value("session").(Session)
+	return v
+}
+
 func (s *S) serveWS(w http.ResponseWriter, r *http.Request) error {
 	ctx := r.Context()
 
@@ -167,5 +172,11 @@ func (s *S) serveWS(w http.ResponseWriter, r *http.Request) error {
 }
 
 func (s *S) serveV1(w http.ResponseWriter, r *http.Request) error {
-	return fmt.Errorf("not impl: v1")
+	ctx := r.Context()
+	switch r.Method + r.URL.Path {
+	case "PUT/v1/state/" + s.Session(ctx).ID + "/party":
+		return nil
+	}
+	http.NotFound(w, r)
+	return nil
 }