diff --git a/index.d.ts b/index.d.ts
index 721a1db..ac3debe 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1,3 +1,5 @@
+/// <reference types="jest" />
+
 declare namespace jest {
   interface Matchers<R> {
     toMatchJSON(expected: Record<string, unknown>): R;