diff --git a/readme.md b/readme.md
index b781b2f..9708c45 100644
--- a/readme.md
+++ b/readme.md
@@ -89,7 +89,7 @@ TypedJSON.mapType(Decimal, {
 class MappedTypes {
 
     @jsonMember
-    cryptoKey: BigInt;
+    cryptoKey: bigint;
 
     @jsonMember
     money: Decimal;