diff --git a/build/index.js b/build/index.js
index 9bbf73d..e03558e 100644
--- a/build/index.js
+++ b/build/index.js
@@ -10,6 +10,9 @@ const common = {
 esbuild.build({
   ...common,
   outdir: 'dist/esm',
+  outExtension: {
+    '.js': '.mjs'
+  },
   bundle: true,
   format: 'esm',
 })
@@ -17,6 +20,9 @@ esbuild.build({
 esbuild.build({
   ...common,
   outdir: 'dist/cjs',
+  outExtension: {
+    '.js': '.cjs'
+  },
   bundle: true,
   format: 'cjs',
 })
diff --git a/package-lock.json b/package-lock.json
index ce95605..0231e11 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,15 +1,15 @@
 {
   "name": "serializable-bptree",
-  "version": "3.2.4",
+  "version": "3.3.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "serializable-bptree",
-      "version": "3.2.4",
+      "version": "3.3.0",
       "license": "MIT",
       "dependencies": {
-        "cachebranch": "^1.1.0"
+        "cachebranch": "^1.2.0"
       },
       "devDependencies": {
         "@types/jest": "^29.5.8",
@@ -1756,9 +1756,9 @@
       "dev": true
     },
     "node_modules/cachebranch": {
-      "version": "1.1.0",
-      "resolved": "https://registry.npmjs.org/cachebranch/-/cachebranch-1.1.0.tgz",
-      "integrity": "sha512-YoHzz/1v6iyJD332FmKYI5ozluAyTguHF3bldmv3Me+kWd4BDpdk/ak1bwymS+Emb/roM7TYLKmT1WOFKi4rug==",
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/cachebranch/-/cachebranch-1.2.0.tgz",
+      "integrity": "sha512-P1FS2TILnv4wiZMtcm1zEmvjRSvpPvz8rk+Mes5jPdRJdssEFaGnMVZkOoikDM+eCQP01kN8+BCc1/LssidBoA==",
       "dependencies": {
         "@ungap/structured-clone": "^1.2.0"
       }
diff --git a/package.json b/package.json
index 02fc55b..b587bac 100644
--- a/package.json
+++ b/package.json
@@ -1,14 +1,14 @@
 {
   "name": "serializable-bptree",
-  "version": "3.2.4",
+  "version": "3.3.0",
   "description": "Store the B+tree flexibly, not only in-memory.",
-  "main": "dist/cjs/index.js",
-  "module": "dist/esm/index.js",
+  "main": "dist/cjs/index.cjs",
+  "module": "dist/esm/index.mjs",
   "typings": "dist/typings/index.d.ts",
   "exports": {
     ".": {
-      "import": "./dist/esm/index.js",
-      "require": "./dist/cjs/index.js",
+      "import": "./dist/esm/index.mjs",
+      "require": "./dist/cjs/index.cjs",
       "types": "./dist/typings/index.d.ts"
     }
   },
@@ -43,6 +43,6 @@
     "typescript": "^5.2.2"
   },
   "dependencies": {
-    "cachebranch": "^1.1.0"
+    "cachebranch": "^1.2.0"
   }
 }