diff --git a/package.json b/package.json
index 0ee01277..4af547d9 100644
--- a/package.json
+++ b/package.json
@@ -2,7 +2,7 @@
   "name": "@phillips/seldon",
   "version": "1.8.0",
   "type": "module",
-  "main": "./dist/index.js",
+  "main": "./dist/index.cjs",
   "module": "./dist/index.js",
   "types": "./dist/index.d.ts",
   "exports": {
diff --git a/vite.config.ts b/vite.config.ts
index 5109d20e..b02384b4 100644
--- a/vite.config.ts
+++ b/vite.config.ts
@@ -54,18 +54,28 @@ export default defineConfig({
       // Could also be a dictionary or array of multiple entry points
       entry: ['index.ts'],
       name: 'seldon',
-      formats: ['es'],
+      formats: ['es', 'cjs'],
     },
 
     rollupOptions: {
       input: 'src/index.ts',
-      output: {
+      output: [
+        {
         dir: 'dist',
+        format: 'es',
         preserveModules: true,
         preserveModulesRoot: 'src',
         chunkFileNames: '[name].js',
         entryFileNames: '[name].js',
       },
+      {
+        dir: 'dist',
+        format: 'cjs',
+        preserveModulesRoot: 'src',
+        chunkFileNames: '[name].cjs',
+        entryFileNames: '[name].cjs',
+      },
+    ],
       // make sure to externalize deps that shouldn't be bundled
       // into your library
       external: [...Object.keys(packageJson.peerDependencies)],