diff --git a/src/index.ts b/src/index.ts
index 5636e659..6e071406 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,4 +1,10 @@
-import { Class, JSONValue, SuperJSONResult, SuperJSONValue } from './types.js';
+import {
+  Class,
+  JSONValue,
+  SerializableJSONValue,
+  SuperJSONResult,
+  SuperJSONValue,
+} from './types.js';
 import { ClassRegistry, RegisterOptions } from './class-registry.js';
 import { Registry } from './registry.js';
 import {
@@ -13,6 +19,14 @@ import {
 } from './plainer.js';
 import { copy } from 'copy-anything';
 
+export {
+  CustomTransfomer,
+  CustomTransformerRegistry,
+  JSONValue,
+  SerializableJSONValue,
+  SuperJSONValue,
+};
+
 export default class SuperJSON {
   /**
    * If true, SuperJSON will make sure only one instance of referentially equal objects are serialized and the rest are replaced with `null`.