diff --git a/package.json b/package.json
index ca9aab1..9daf7e8 100644
--- a/package.json
+++ b/package.json
@@ -1,11 +1,10 @@
 {
   "name": "@datawheel/data-explorer",
-  "version": "0.3.3",
+  "version": "0.3.4",
   "exports": {
     ".": {
       "types": "./dist/main.d.ts",
-      "import": "./dist/main.js",
-      "require": "./dist/main.cjs"
+      "import": "./dist/main.js"
     }
   },
   "types": "./dist/main.d.ts",
diff --git a/tsup.config.js b/tsup.config.js
index fa6f5e5..b28c772 100644
--- a/tsup.config.js
+++ b/tsup.config.js
@@ -1,14 +1,17 @@
+
 //@ts-check
 import {defineConfig} from "tsup"
 
 export default defineConfig(options => ({
   clean: !options.watch,
   entry: ["src/main.ts"],
-  format: ["esm", "cjs"],
+  format: ["esm"],
+  outExtension() {
+    return {js: ".js"}
+  },
   shims: true,
   sourcemap: !!options.watch,
   splitting: false,
   treeshake: true,
-  declaration: true,
-  dts: true,
+  dts: true,  // This enables type declaration file generation
 }));
\ No newline at end of file