diff --git a/src/utils/Member.ts b/src/utils/Member.ts
new file mode 100644
index 000000000..6f4d96ad6
--- /dev/null
+++ b/src/utils/Member.ts
@@ -0,0 +1,3 @@
+type Member<Opts, Res> = (opts: Opts) => Promise<Res>;
+
+export default Member;