diff --git a/src/types.d.ts b/src/types.d.ts
index 5ebe0d8..be81bab 100644
--- a/src/types.d.ts
+++ b/src/types.d.ts
@@ -68,6 +68,10 @@ declare global {
 	interface Window {
 		globalThis: typeof globalThis;
 	}
+
+	type Writable<T> = {
+		-readonly [P in keyof T]: T[P];
+	}
 }
 
 /** Token interface */