diff --git a/package-lock.json b/package-lock.json
index 2edad6ea8..f9c160dbf 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,6 +1,6 @@
 {
   "name": "gentype",
-  "version": "3.50.0",
+  "version": "4.0.0",
   "lockfileVersion": 2,
   "requires": true,
   "packages": {
diff --git a/package.json b/package.json
index 0c0299c72..ccc8959fa 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "gentype",
-  "version": "3.50.0",
+  "version": "4.0.0",
   "private": true,
   "description": "Use Reason values from Javascript: vanilla, or TypeScript/FlowType-annotated",
   "license": "MIT",
diff --git a/src/Version.ml b/src/Version.ml
index 0007f3d98..0b70e0206 100644
--- a/src/Version.ml
+++ b/src/Version.ml
@@ -1,4 +1,4 @@
 
 (* CREATED BY genType/scripts/bump_version_module.js *)
 (* DO NOT MODIFY BY HAND, WILL BE AUTOMATICALLY UPDATED BY npm version *)
-let version = "3.50.0";
+let version = "4.0.0";