diff --git a/src/puter-js/package.json b/src/puter-js/package.json
index 3fac79ee9..7451ae763 100644
--- a/src/puter-js/package.json
+++ b/src/puter-js/package.json
@@ -3,6 +3,7 @@
   "version": "1.0.0",
   "description": "",
   "main": "index.js",
+  "type": "module",
   "scripts": {
     "start-server": "npx http-server --cors -c-1",
     "start-webpack": "webpack && webpack --output-filename puter.dev.js --watch --devtool source-map",
diff --git a/src/puter-js/src/clitest.js b/src/puter-js/src/clitest.js
new file mode 100644
index 000000000..10ce2935c
--- /dev/null
+++ b/src/puter-js/src/clitest.js
@@ -0,0 +1 @@
+import puter from './index.js';
diff --git a/src/puter-js/src/index.js b/src/puter-js/src/index.js
index 7a241f0e0..e4014f2df 100644
--- a/src/puter-js/src/index.js
+++ b/src/puter-js/src/index.js
@@ -33,7 +33,7 @@ import Perms from './modules/Perms.js';
 //       (using defaultGUIOrigin breaks locally-hosted apps)
 const PROD_ORIGIN = 'https://puter.com';
 
-window.puter = (function() {
+export default window.puter = (function() {
     'use strict';
 
     class Puter{
diff --git a/src/puter-js/src/lib/filesystem/APIFS.js b/src/puter-js/src/lib/filesystem/APIFS.js
index 308a99eb8..baea88b1c 100644
--- a/src/puter-js/src/lib/filesystem/APIFS.js
+++ b/src/puter-js/src/lib/filesystem/APIFS.js
@@ -1,6 +1,6 @@
 import * as utils from '../utils.js';
 import putility from "@heyputer/putility";
-import { TeePromise } from "@heyputer/putility/src/libs/promise";
+import { TeePromise } from "@heyputer/putility/src/libs/promise.js";
 import getAbsolutePathForApp from '../../modules/FileSystem/utils/getAbsolutePathForApp.js';
 import { TFilesystem } from './definitions.js';
 
diff --git a/src/puter-js/src/lib/filesystem/CacheFS.js b/src/puter-js/src/lib/filesystem/CacheFS.js
index 9e90b88cc..f2541d0e1 100644
--- a/src/puter-js/src/lib/filesystem/CacheFS.js
+++ b/src/puter-js/src/lib/filesystem/CacheFS.js
@@ -1,7 +1,7 @@
 import putility from "@heyputer/putility";
-import { RWLock } from "@heyputer/putility/src/libs/promise";
-import { ProxyFilesystem, TFilesystem } from "./definitions";
-import { uuidv4 } from "../utils";
+import { RWLock } from "@heyputer/putility/src/libs/promise.js";
+import { ProxyFilesystem, TFilesystem } from "./definitions.js";
+import { uuidv4 } from "../utils.js";
 
 export const ROOT_UUID = '00000000-0000-0000-0000-000000000000';
 const TTL = 5 * 1000;
diff --git a/src/puter-js/src/lib/filesystem/PostMessageFS.js b/src/puter-js/src/lib/filesystem/PostMessageFS.js
index 74e995b44..00e974d1f 100644
--- a/src/puter-js/src/lib/filesystem/PostMessageFS.js
+++ b/src/puter-js/src/lib/filesystem/PostMessageFS.js
@@ -1,5 +1,5 @@
 import putility from "@heyputer/putility";
-import { TFilesystem } from "./definitions";
+import { TFilesystem } from "./definitions.js";
 
 const example =     {
         "id": "f485f1ba-de07-422c-8c4b-c2da057d4a44",
diff --git a/src/puter-js/src/lib/http.js b/src/puter-js/src/lib/http.js
index 935f6d810..ec3ac2bb0 100644
--- a/src/puter-js/src/lib/http.js
+++ b/src/puter-js/src/lib/http.js
@@ -1,5 +1,5 @@
 import putility from "@heyputer/putility";
-import EventListener from "./EventListener";
+import EventListener from "./EventListener.js";
 
 // TODO: this inheritance is an anti-pattern; we should use
 //       a trait or mixin for event emitters.
diff --git a/src/puter-js/src/modules/PuterDialog.js b/src/puter-js/src/modules/PuterDialog.js
index 1c1790318..00a337f9f 100644
--- a/src/puter-js/src/modules/PuterDialog.js
+++ b/src/puter-js/src/modules/PuterDialog.js
@@ -417,4 +417,4 @@ class PuterDialog extends HTMLElement {
 }
 customElements.define('puter-dialog', PuterDialog);
 
-module.exports = PuterDialog;
\ No newline at end of file
+export default PuterDialog;
diff --git a/src/puter-js/src/modules/Util.js b/src/puter-js/src/modules/Util.js
index ef7b3e594..f3c5aa525 100644
--- a/src/puter-js/src/modules/Util.js
+++ b/src/puter-js/src/modules/Util.js
@@ -1,4 +1,4 @@
-import { $SCOPE, CallbackManager, Dehydrator, Hydrator } from "../lib/xdrpc";
+import { $SCOPE, CallbackManager, Dehydrator, Hydrator } from "../lib/xdrpc.js";
 
 /**
  * The Util module exposes utilities within puter.js itself.
diff --git a/src/puter-js/src/modules/networking/PTLS.js b/src/puter-js/src/modules/networking/PTLS.js
index ed90cafc5..526a9c5de 100644
--- a/src/puter-js/src/modules/networking/PTLS.js
+++ b/src/puter-js/src/modules/networking/PTLS.js
@@ -2,7 +2,7 @@
  * This file uses https://github.com/MercuryWorkshop/rustls-wasm authored by GitHub:@r58Playz under the MIT License
  */
 
-import { PSocket } from "./PSocket";
+import { PSocket } from "./PSocket.js";
 
 let rustls = undefined;
 
diff --git a/src/puter-js/src/services/Filesystem.js b/src/puter-js/src/services/Filesystem.js
index 699dc9abe..7b9832ac1 100644
--- a/src/puter-js/src/services/Filesystem.js
+++ b/src/puter-js/src/services/Filesystem.js
@@ -1,7 +1,7 @@
 import putility from "@heyputer/putility";
-import { PuterAPIFilesystem } from "../lib/filesystem/APIFS";
-import { CachedFilesystem } from "../lib/filesystem/CacheFS";
-import { ProxyFilesystem, TFilesystem } from "../lib/filesystem/definitions";
+import { PuterAPIFilesystem } from "../lib/filesystem/APIFS.js";
+import { CachedFilesystem } from "../lib/filesystem/CacheFS.js";
+import { ProxyFilesystem, TFilesystem } from "../lib/filesystem/definitions.js";
 import io from '../lib/socket.io/socket.io.esm.min.js';
 import { PostMessageFilesystem } from "../lib/filesystem/PostMessageFS.js";
 
diff --git a/src/puter-js/webpack.config.js b/src/puter-js/webpack.config.js
index 4f160a0a0..8cd71caf3 100644
--- a/src/puter-js/webpack.config.js
+++ b/src/puter-js/webpack.config.js
@@ -1,9 +1,18 @@
-const path = require('path');
-const webpack = require('webpack');
+import path from 'node:path';
+import webpack from 'webpack';
+
+// '__dirname' isn't defined by default in ES modules.
+// We didn't really want to migrate this file to ESM because
+// it's config for tooling that only runs in node, but alas
+// if package.json says "type": "module" then we have to use
+// ESM syntax everywhere unless we rename this to a .cjs file
+// and add an extra flag everywhere we use webpack.
+import { fileURLToPath } from 'url';
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
 
 console.log('ENV CHECK!!!', process.env.PUTER_ORIGIN, process.env.PUTER_API_ORIGIN);
 
-module.exports = {
+export default {
   entry: './src/index.js',
   output: {
     filename: 'puter.js',