Proxy server to inject shim (#178)

things to test: - [x] allow real URL to open in new window - [x] packaging in electron? - [ ] does it work on windows? - [x] make sure it works with older apps - [x] what about cache / reuse? - maybe use a bigger range of ports??

Proxy server to inject shim (#178)
5966dd7f · Will Chen · GitHub · 63e41454 · 5966dd7f · 5966dd7f
--- a/forge.config.ts
+++ b/forge.config.ts
@@ -22,6 +22,9 @@ const ignore = (file: string) => {
  if (file.startsWith("/scaffold")) {
    return false;
  }
+  if (file.startsWith("/worker")) {
+    return false;
+  }
  if (file.startsWith("/node_modules/better-sqlite3")) {
    return false;
  }

--- a/package-lock.json
+++ b/package-lock.json
 {
  "name": "dyad",
-  "version": "0.4.0",
+  "version": "0.5.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "dyad",
-      "version": "0.4.0",
+      "version": "0.5.0",
      "license": "MIT",
      "dependencies": {
        "@ai-sdk/anthropic": "^1.2.8",
@@ -66,6 +66,7 @@
        "shell-env": "^4.0.1",
        "shiki": "^3.2.1",
        "sonner": "^2.0.3",
+        "stacktrace-js": "^2.0.2",
        "tailwind-merge": "^3.1.0",
        "tailwindcss": "^4.1.3",
        "tree-kill": "^1.2.2",
@@ -9657,6 +9658,15 @@
        "is-arrayish": "^0.2.1"
      }
    },
+    "node_modules/error-stack-parser": {
+      "version": "2.1.4",
+      "resolved": "https://registry.npmjs.org/error-stack-parser/-/error-stack-parser-2.1.4.tgz",
+      "integrity": "sha512-Sk5V6wVazPhq5MhpO+AUxJn5x7XSXGl1R93Vn7i+zS15KDVxQijejNCrz8340/2bgLBjR9GtEG8ZVKONDjcqGQ==",
+      "license": "MIT",
+      "dependencies": {
+        "stackframe": "^1.3.4"
+      }
+    },
    "node_modules/es-abstract": {
      "version": "1.23.9",
      "resolved": "https://registry.npmjs.org/es-abstract/-/es-abstract-1.23.9.tgz",
@@ -17564,6 +17574,15 @@
        "node": "^12.13.0 || ^14.15.0 || >=16.0.0"
      }
    },
+    "node_modules/stack-generator": {
+      "version": "2.0.10",
+      "resolved": "https://registry.npmjs.org/stack-generator/-/stack-generator-2.0.10.tgz",
+      "integrity": "sha512-mwnua/hkqM6pF4k8SnmZ2zfETsRUpWXREfA/goT8SLCV4iOFa4bzOX2nDipWAZFPTjLvQB82f5yaodMVhK0yJQ==",
+      "license": "MIT",
+      "dependencies": {
+        "stackframe": "^1.3.4"
+      }
+    },
    "node_modules/stack-utils": {
      "version": "2.0.6",
      "resolved": "https://registry.npmjs.org/stack-utils/-/stack-utils-2.0.6.tgz",
@@ -17592,6 +17611,42 @@
      "dev": true,
      "license": "MIT"
    },
+    "node_modules/stackframe": {
+      "version": "1.3.4",
+      "resolved": "https://registry.npmjs.org/stackframe/-/stackframe-1.3.4.tgz",
+      "integrity": "sha512-oeVtt7eWQS+Na6F//S4kJ2K2VbRlS9D43mAlMyVpVWovy9o+jfgH8O9agzANzaiLjclA0oYzUXEM4PurhSUChw==",
+      "license": "MIT"
+    },
+    "node_modules/stacktrace-gps": {
+      "version": "3.1.2",
+      "resolved": "https://registry.npmjs.org/stacktrace-gps/-/stacktrace-gps-3.1.2.tgz",
+      "integrity": "sha512-GcUgbO4Jsqqg6RxfyTHFiPxdPqF+3LFmQhm7MgCuYQOYuWyqxo5pwRPz5d/u6/WYJdEnWfK4r+jGbyD8TSggXQ==",
+      "license": "MIT",
+      "dependencies": {
+        "source-map": "0.5.6",
+        "stackframe": "^1.3.4"
+      }
+    },
+    "node_modules/stacktrace-gps/node_modules/source-map": {
+      "version": "0.5.6",
+      "resolved": "https://registry.npmjs.org/source-map/-/source-map-0.5.6.tgz",
+      "integrity": "sha512-MjZkVp0NHr5+TPihLcadqnlVoGIoWo4IBHptutGh9wI3ttUYvCG26HkSuDi+K6lsZ25syXJXcctwgyVCt//xqA==",
+      "license": "BSD-3-Clause",
+      "engines": {
+        "node": ">=0.10.0"
+      }
+    },
+    "node_modules/stacktrace-js": {
+      "version": "2.0.2",
+      "resolved": "https://registry.npmjs.org/stacktrace-js/-/stacktrace-js-2.0.2.tgz",
+      "integrity": "sha512-Je5vBeY4S1r/RnLydLl0TBTi3F2qdfWmYsGvtfZgEI+SCprPppaIhQf5nGcal4gI4cGpCV/duLcAzT1np6sQqg==",
+      "license": "MIT",
+      "dependencies": {
+        "error-stack-parser": "^2.0.6",
+        "stack-generator": "^2.0.5",
+        "stacktrace-gps": "^3.0.4"
+      }
+    },
    "node_modules/state-local": {
      "version": "1.0.7",
      "resolved": "https://registry.npmjs.org/state-local/-/state-local-1.0.7.tgz",

--- a/package.json
+++ b/package.json
@@ -131,6 +131,7 @@
    "shell-env": "^4.0.1",
    "shiki": "^3.2.1",
    "sonner": "^2.0.3",
+    "stacktrace-js": "^2.0.2",
    "tailwind-merge": "^3.1.0",
    "tailwindcss": "^4.1.3",
    "tree-kill": "^1.2.2",

--- a/scaffold/package.json
+++ b/scaffold/package.json
@@ -56,7 +56,6 @@
    "react-router-dom": "^6.26.2",
    "recharts": "^2.12.7",
    "sonner": "^1.5.0",
-    "stacktrace-js": "^2.0.2",
    "tailwind-merge": "^2.5.2",
    "tailwindcss-animate": "^1.0.7",
    "vaul": "^0.9.3",

--- a/scaffold/pnpm-lock.yaml
+++ b/scaffold/pnpm-lock.yaml
@@ -143,9 +143,6 @@ importers:
      sonner:
        specifier: ^1.5.0
        version: 1.7.4(react-dom@18.3.1(react@18.3.1))(react@18.3.1)
-      stacktrace-js:
-        specifier: ^2.0.2
-        version: 2.0.2
      tailwind-merge:
        specifier: ^2.5.2
        version: 2.6.0
@@ -1618,9 +1615,6 @@ packages:
  emoji-regex@9.2.2:
    resolution: {integrity: sha512-L18DaJsXSUk2+42pv8mLs5jJT2hqFkFE4j21wOmgbUqsZ2hL72NsUU785g9RXgo3s0ZNgVl42TiHp3ZtOv/Vyg==}
-  error-stack-parser@2.1.4:
-    resolution: {integrity: sha512-Sk5V6wVazPhq5MhpO+AUxJn5x7XSXGl1R93Vn7i+zS15KDVxQijejNCrz8340/2bgLBjR9GtEG8ZVKONDjcqGQ==}
  esbuild@0.25.3:
    resolution: {integrity: sha512-qKA6Pvai73+M2FtftpNKRxJ78GIjmFXFxd/1DVBqGo/qNhLSfv+G12n9pNoWdytJC8U00TrViOwpjT0zgqQS8Q==}
    engines: {node: '>=18'}
@@ -2230,22 +2224,6 @@ packages:
    resolution: {integrity: sha512-UXWMKhLOwVKb728IUtQPXxfYU+usdybtUrK/8uGE8CQMvrhOpwvzDBwj0QhSL7MQc7vIsISBG8VQ8+IDQxpfQA==}
    engines: {node: '>=0.10.0'}
-  source-map@0.5.6:
-    resolution: {integrity: sha512-MjZkVp0NHr5+TPihLcadqnlVoGIoWo4IBHptutGh9wI3ttUYvCG26HkSuDi+K6lsZ25syXJXcctwgyVCt//xqA==}
-    engines: {node: '>=0.10.0'}
-  stack-generator@2.0.10:
-    resolution: {integrity: sha512-mwnua/hkqM6pF4k8SnmZ2zfETsRUpWXREfA/goT8SLCV4iOFa4bzOX2nDipWAZFPTjLvQB82f5yaodMVhK0yJQ==}
-  stackframe@1.3.4:
-    resolution: {integrity: sha512-oeVtt7eWQS+Na6F//S4kJ2K2VbRlS9D43mAlMyVpVWovy9o+jfgH8O9agzANzaiLjclA0oYzUXEM4PurhSUChw==}
-  stacktrace-gps@3.1.2:
-    resolution: {integrity: sha512-GcUgbO4Jsqqg6RxfyTHFiPxdPqF+3LFmQhm7MgCuYQOYuWyqxo5pwRPz5d/u6/WYJdEnWfK4r+jGbyD8TSggXQ==}
-  stacktrace-js@2.0.2:
-    resolution: {integrity: sha512-Je5vBeY4S1r/RnLydLl0TBTi3F2qdfWmYsGvtfZgEI+SCprPppaIhQf5nGcal4gI4cGpCV/duLcAzT1np6sQqg==}
  string-width@4.2.3:
    resolution: {integrity: sha512-wKyQRQpjJ0sIp62ErSZdGsjMJWsap5oRNihHhu6G7JVO/9jIB6UyevL+tXuOqrng8j/cxKTWyWUwvSTriiZz/g==}
    engines: {node: '>=8'}
@@ -3782,10 +3760,6 @@ snapshots:
  emoji-regex@9.2.2: {}
-  error-stack-parser@2.1.4:
-    dependencies:
-      stackframe: 1.3.4
  esbuild@0.25.3:
    optionalDependencies:
      '@esbuild/aix-ppc64': 0.25.3
@@ -4389,25 +4363,6 @@ snapshots:
  source-map-js@1.2.1: {}
-  source-map@0.5.6: {}
-  stack-generator@2.0.10:
-    dependencies:
-      stackframe: 1.3.4
-  stackframe@1.3.4: {}
-  stacktrace-gps@3.1.2:
-    dependencies:
-      source-map: 0.5.6
-      stackframe: 1.3.4
-  stacktrace-js@2.0.2:
-    dependencies:
-      error-stack-parser: 2.1.4
-      stack-generator: 2.0.10
-      stacktrace-gps: 3.1.2
  string-width@4.2.3:
    dependencies:
      emoji-regex: 8.0.0

--- a/scaffold/vite.config.ts
+++ b/scaffold/vite.config.ts
-import { defineConfig, Plugin, HtmlTagDescriptor } from "vite";
+import { defineConfig } from "vite";
 import react from "@vitejs/plugin-react-swc";
 import path from "path";
-import fs from "fs";
-export function devErrorAndNavigationPlugin(): Plugin {
-  let stacktraceJsContent: string | null = null;
-  let dyadShimContent: string | null = null;
-  return {
-    name: "dev-error-and-navigation-handler",
-    apply: "serve",
-    configResolved() {
-      const stackTraceLibPath = path.join(
-        "node_modules",
-        "stacktrace-js",
-        "dist",
-        "stacktrace.min.js",
-      );
-      if (stackTraceLibPath) {
-        try {
-          stacktraceJsContent = fs.readFileSync(stackTraceLibPath, "utf-8");
-        } catch (error) {
-          console.error(
-            `[dyad-shim] Failed to read stacktrace.js from ${stackTraceLibPath}:`,
-            error,
-          );
-          stacktraceJsContent = null;
-        }
-      } else {
-        console.error(`[dyad-shim] stacktrace.js not found.`);
-      }
-      const dyadShimPath = path.join("dyad-shim.js");
-      if (dyadShimPath) {
-        try {
-          dyadShimContent = fs.readFileSync(dyadShimPath, "utf-8");
-        } catch (error) {
-          console.error(
-            `[dyad-shim] Failed to read dyad-shim from ${dyadShimPath}:`,
-            error,
-          );
-          dyadShimContent = null;
-        }
-      } else {
-        console.error(`[dyad-shim] stacktrace.js not found.`);
-      }
-    },
-    transformIndexHtml(html) {
-      const tags: HtmlTagDescriptor[] = [];
-      // 1. Inject stacktrace.js
-      if (stacktraceJsContent) {
-        tags.push({
-          tag: "script",
-          injectTo: "head-prepend",
-          children: stacktraceJsContent,
-        });
-      } else {
-        tags.push({
-          tag: "script",
-          injectTo: "head-prepend",
-          children:
-            "console.warn('[dyad-shim] stacktrace.js library was not injected.');",
-        });
-      }
-      // 2. Inject dyad shim
-      if (dyadShimContent) {
-        tags.push({
-          tag: "script",
-          injectTo: "head-prepend",
-          children: dyadShimContent,
-        });
-      } else {
-        tags.push({
-          tag: "script",
-          injectTo: "head-prepend",
-          children: "console.warn('[dyad-shim] dyad shim was not injected.');",
-        });
-      }
-      return { html, tags };
-    },
-  };
-}
 export default defineConfig(() => ({
  server: {
    host: "::",
    port: 8080,
  },
-  plugins: [react(), devErrorAndNavigationPlugin()],
+  plugins: [react()],
  resolve: {
    alias: {
      "@": path.resolve(__dirname, "./src"),

--- a/src/atoms/appAtoms.ts
+++ b/src/atoms/appAtoms.ts
@@ -11,8 +11,9 @@ export const previewModeAtom = atom<"preview" | "code">("preview");
 export const selectedVersionIdAtom = atom<string | null>(null);
 export const appOutputAtom = atom<AppOutput[]>([]);
 export const appUrlAtom = atom<
-  { appUrl: string; appId: number } | { appUrl: null; appId: null }
+  | { appUrl: string; appId: number; originalUrl: string }
->({ appUrl: null, appId: null });
+  | { appUrl: null; appId: null; originalUrl: null }
+>({ appUrl: null, appId: null, originalUrl: null });
 export const userSettingsAtom = atom<UserSettings | null>(null);
 // Atom for storing allow-listed environment variables

--- a/src/components/preview_panel/PreviewIframe.tsx
+++ b/src/components/preview_panel/PreviewIframe.tsx
@@ -106,7 +106,7 @@ const ErrorBanner = ({ error, onDismiss, onAIFix }: ErrorBannerProps) => {
 // Preview iframe component
 export const PreviewIframe = ({ loading }: { loading: boolean }) => {
  const selectedAppId = useAtomValue(selectedAppIdAtom);
-  const { appUrl } = useAtomValue(appUrlAtom);
+  const { appUrl, originalUrl } = useAtomValue(appUrlAtom);
  const setAppOutput = useSetAtom(appOutputAtom);
  // State to trigger iframe reload
  const [reloadKey, setReloadKey] = useState(0);
@@ -429,8 +429,8 @@ export const PreviewIframe = ({ loading }: { loading: boolean }) => {
        <div className="flex space-x-1">
          <button
            onClick={() => {
-              if (appUrl) {
+              if (originalUrl) {
-                IpcClient.getInstance().openExternalUrl(appUrl);
+                IpcClient.getInstance().openExternalUrl(originalUrl);
              }
            }}
            className="p-1 rounded hover:bg-gray-200 dark:hover:bg-gray-700 disabled:opacity-50 disabled:cursor-not-allowed dark:text-gray-300"

--- a/src/hooks/useRunApp.ts
+++ b/src/hooks/useRunApp.ts
@@ -9,6 +9,7 @@ import {
  selectedAppIdAtom,
 } from "@/atoms/appAtoms";
 import { useAtom, useAtomValue, useSetAtom } from "jotai";
+import { AppOutput } from "@/ipc/ipc_types";
 export function useRunApp() {
  const [loading, setLoading] = useState(false);
@@ -18,6 +19,29 @@ export function useRunApp() {
  const setPreviewPanelKey = useSetAtom(previewPanelKeyAtom);
  const appId = useAtomValue(selectedAppIdAtom);
  const setPreviewErrorMessage = useSetAtom(previewErrorMessageAtom);
+  const processProxyServerOutput = (output: AppOutput) => {
+    const matchesProxyServerStart = output.message.includes(
+      "[dyad-proxy-server]started=[",
+    );
+    if (matchesProxyServerStart) {
+      // Extract both proxy URL and original URL using regex
+      const proxyUrlMatch = output.message.match(
+        /\[dyad-proxy-server\]started=\[(.*?)\]/,
+      );
+      const originalUrlMatch = output.message.match(/original=\[(.*?)\]/);
+      if (proxyUrlMatch && proxyUrlMatch[1]) {
+        const proxyUrl = proxyUrlMatch[1];
+        const originalUrl = originalUrlMatch && originalUrlMatch[1];
+        setAppUrlObj({
+          appUrl: proxyUrl,
+          appId: appId!,
+          originalUrl: originalUrl!,
+        });
+      }
+    }
+  };
  const runApp = useCallback(async (appId: number) => {
    setLoading(true);
    try {
@@ -26,7 +50,7 @@ export function useRunApp() {
      // Clear the URL and add restart message
      if (appUrlObj?.appId !== appId) {
-        setAppUrlObj({ appUrl: null, appId: null });
+        setAppUrlObj({ appUrl: null, appId: null, originalUrl: null });
      }
      setAppOutput((prev) => [
        ...prev,
@@ -41,11 +65,7 @@ export function useRunApp() {
      setApp(app);
      await ipcClient.runApp(appId, (output) => {
        setAppOutput((prev) => [...prev, output]);
-        // Check if the output contains a localhost URL
+        processProxyServerOutput(output);
-        const urlMatch = output.message.match(/(https?:\/\/localhost:\d+\/?)/);
-        if (urlMatch) {
-          setAppUrlObj({ appUrl: urlMatch[1], appId });
-        }
      });
      setPreviewErrorMessage(undefined);
    } catch (error) {
@@ -100,7 +120,7 @@ export function useRunApp() {
        );
        // Clear the URL and add restart message
-        setAppUrlObj({ appUrl: null, appId: null });
+        setAppUrlObj({ appUrl: null, appId: null, originalUrl: null });
        setAppOutput((prev) => [
          ...prev,
          {
@@ -124,13 +144,7 @@ export function useRunApp() {
              onHotModuleReload();
              return;
            }
-            // Check if the output contains a localhost URL
+            processProxyServerOutput(output);
-            const urlMatch = output.message.match(
-              /(https?:\/\/localhost:\d+\/?)/,
-            );
-            if (urlMatch) {
-              setAppUrlObj({ appUrl: urlMatch[1], appId });
-            }
          },
          removeNodeModules,
        );

--- a/src/ipc/handlers/app_handlers.ts
+++ b/src/ipc/handlers/app_handlers.ts
@@ -33,10 +33,14 @@ import log from "electron-log";
 import { getSupabaseProjectName } from "../../supabase_admin/supabase_management_client";
 import { createLoggedHandler } from "./safe_handle";
 import { getLanguageModelProviders } from "../shared/language_model_helpers";
+import { startProxy } from "../utils/start_proxy_server";
+import { Worker } from "worker_threads";
 const logger = log.scope("app_handlers");
 const handle = createLoggedHandler(logger);
+let proxyWorker: Worker | null = null;
 // Needed, otherwise electron in MacOS/Linux will not be able
 // to find node/pnpm.
 fixPath();
@@ -50,8 +54,13 @@ async function executeApp({
  appId: number;
  event: Electron.IpcMainInvokeEvent;
 }): Promise<void> {
+  if (proxyWorker) {
+    proxyWorker.terminate();
+    proxyWorker = null;
+  }
  await executeAppLocalNode({ appPath, appId, event });
 }
 async function executeAppLocalNode({
  appPath,
  appId,
@@ -90,14 +99,27 @@ async function executeAppLocalNode({
  runningApps.set(appId, { process, processId: currentProcessId });
  // Log output
-  process.stdout?.on("data", (data) => {
+  process.stdout?.on("data", async (data) => {
    const message = util.stripVTControlCharacters(data.toString());
    logger.debug(`App ${appId} (PID: ${process.pid}) stdout: ${message}`);
    event.sender.send("app:output", {
      type: "stdout",
      message,
      appId,
    });
+    const urlMatch = message.match(/(https?:\/\/localhost:\d+\/?)/);
+    if (urlMatch) {
+      proxyWorker = await startProxy(urlMatch[1], {
+        onStarted: (proxyUrl) => {
+          event.sender.send("app:output", {
+            type: "stdout",
+            message: `[dyad-proxy-server]started=[${proxyUrl}] original=[${urlMatch[1]}]`,
+            appId,
+          });
+        },
+      });
+    }
  });
  process.stderr?.on("data", (data) => {

--- a/src/ipc/utils/port_utils.ts
+++ b/src/ipc/utils/port_utils.ts
+import net from "net";
+export function findAvailablePort(
+  minPort: number,
+  maxPort: number,
+): Promise<number> {
+  return new Promise((resolve, reject) => {
+    let attempts = 0;
+    const maxAttempts = 3;
+    function tryPort() {
+      if (attempts >= maxAttempts) {
+        reject(
+          new Error(
+            `Failed to find an available port after ${maxAttempts} attempts.`,
+          ),
+        );
+        return;
+      }
+      attempts++;
+      const port =
+        Math.floor(Math.random() * (maxPort - minPort + 1)) + minPort;
+      const server = net.createServer();
+      server.once("error", (err: any) => {
+        if (err.code === "EADDRINUSE") {
+          // Port is in use, try another one
+          console.log(`Port ${port} is in use, trying another...`);
+          server.close(() => tryPort());
+        } else {
+          // Other error
+          server.close(() => reject(err));
+        }
+      });
+      server.once("listening", () => {
+        server.close(() => {
+          resolve(port);
+        });
+      });
+      server.listen(port, "localhost");
+    }
+    tryPort();
+  });
+}
--- a/src/ipc/utils/start_proxy_server.ts
+++ b/src/ipc/utils/start_proxy_server.ts
+// startProxy.js – helper to launch proxy.js as a worker
+import { Worker } from "worker_threads";
+import path from "path";
+import { findAvailablePort } from "./port_utils";
+import log from "electron-log";
+const logger = log.scope("start_proxy_server");
+export async function startProxy(
+  targetOrigin: string,
+  opts: {
+    // host?: string;
+    // port?: number;
+    // env?: Record<string, string>;
+    onStarted?: (proxyUrl: string) => void;
+  } = {},
+) {
+  if (!/^https?:\/\//.test(targetOrigin))
+    throw new Error("startProxy: targetOrigin must be absolute http/https URL");
+  const port = await findAvailablePort(50_000, 60_000);
+  logger.info("Found available port", port);
+  const {
+    // host = "localhost",
+    // env = {}, // additional env vars to pass to the worker
+    onStarted,
+  } = opts;
+  const worker = new Worker(
+    path.resolve(__dirname, "..", "..", "worker", "proxy_server.js"),
+    {
+      env: {
+        ...process.env, // inherit parent env
+        TARGET_URL: targetOrigin,
+      },
+      workerData: {
+        targetOrigin,
+        port,
+      },
+    },
+  );
+  worker.on("message", (m) => {
+    logger.info("[proxy]", m);
+    if (typeof m === "string" && m.startsWith("proxy-server-start url=")) {
+      const url = m.substring("proxy-server-start url=".length);
+      onStarted?.(url);
+    }
+  });
+  worker.on("error", (e) => logger.error("[proxy] error:", e));
+  worker.on("exit", (c) => logger.info("[proxy] exit", c));
+  return worker; // let the caller keep a handle if desired
+}
--- a/src/lib/utils.ts
+++ b/src/lib/utils.ts
@@ -6,7 +6,7 @@ export function cn(...inputs: ClassValue[]) {
 }
 /**
- * Generates a cute app name like "blue-fox" or "jumping-zebra"
+ * Generates a cute app name.
 */
 export function generateCuteAppName(): string {
  const adjectives = [
@@ -144,9 +144,64 @@ export function generateCuteAppName(): string {
    "kraken",
  ];
+  const verbs = [
+    "run",
+    "hop",
+    "dash",
+    "zoom",
+    "skip",
+    "jump",
+    "glow",
+    "play",
+    "chirp",
+    "buzz",
+    "flip",
+    "flit",
+    "soar",
+    "dive",
+    "swim",
+    "climb",
+    "sprint",
+    "wiggle",
+    "twirl",
+    "pounce",
+    "bop",
+    "spin",
+    "hum",
+    "roll",
+    "blink",
+    "skid",
+    "kick",
+    "drift",
+    "bloom",
+    "burst",
+    "slide",
+    "bounce",
+    "crawl",
+    "sniff",
+    "peek",
+    "scurry",
+    "nudge",
+    "snap",
+    "swoop",
+    "roam",
+    "trot",
+    "dart",
+    "yawn",
+    "snore",
+    "hug",
+    "nap",
+    "chase",
+    "rest",
+    "wag",
+    "bob",
+    "beam",
+    "cheer",
+  ];
  const randomAdjective =
    adjectives[Math.floor(Math.random() * adjectives.length)];
  const randomAnimal = animals[Math.floor(Math.random() * animals.length)];
+  const randomVerb = verbs[Math.floor(Math.random() * verbs.length)];
-  return `${randomAdjective}-${randomAnimal}`;
+  return `${randomAdjective}-${randomAnimal}-${randomVerb}`;
 }
--- a/scaffold/dyad-shim.js
+++ b/scaffold/dyad-shim.js
 (function () {
+  console.debug("dyad-shim.js loaded via proxy v0.6.0");
  const isInsideIframe = window.parent !== window;
  if (!isInsideIframe) return;

--- a/worker/proxy_server.js
+++ b/worker/proxy_server.js
+/**
+ * proxy.js – zero-dependency worker-based HTTP/WS forwarder
+ */
+const {
+  Worker,
+  isMainThread,
+  parentPort,
+  workerData,
+} = require("worker_threads");
+const http = require("http");
+const https = require("https");
+const { URL } = require("url");
+const fs = require("fs");
+const path = require("path");
+/* ─────────────────── configuration (main thread only) ─────────────────── */
+const LISTEN_HOST = "localhost";
+if (isMainThread) {
+  // Stand-alone mode: fork the worker and pass through the env as-is
+  const w = new Worker(__filename, {
+    workerData: {
+      targetOrigin: process.env.TARGET_URL, // may be undefined
+    },
+  });
+  w.on("message", (m) => console.log("[proxy-worker]", m));
+  w.on("error", (e) => console.error("[proxy-worker] error:", e));
+  w.on("exit", (c) => console.log("[proxy-worker] exited", c));
+  console.log("proxy worker launching …");
+  return; // do not execute the rest of the file in the main thread
+}
+/* ──────────────────────────── worker code ─────────────────────────────── */
+const LISTEN_PORT = process.env.LISTEN_PORT || workerData.port;
+let rememberedOrigin = null; // e.g. "http://localhost:5173"
+/* ---------- pre-configure rememberedOrigin from env or workerData ------- */
+{
+  const fixed = process.env.TARGET_URL || workerData?.targetOrigin;
+  if (fixed) {
+    try {
+      rememberedOrigin = new URL(fixed).origin;
+      parentPort?.postMessage(
+        `[proxy-worker] fixed upstream: ${rememberedOrigin}`,
+      );
+    } catch {
+      throw new Error(
+        `Invalid TARGET_URL "${fixed}". Must be absolute http/https URL.`,
+      );
+    }
+  }
+}
+/* ---------- optional resources for HTML injection ---------------------- */
+let stacktraceJsContent = null;
+let dyadShimContent = null;
+try {
+  const stackTraceLibPath = path.join(
+    __dirname,
+    "..",
+    "node_modules",
+    "stacktrace-js",
+    "dist",
+    "stacktrace.min.js",
+  );
+  stacktraceJsContent = fs.readFileSync(stackTraceLibPath, "utf-8");
+  parentPort?.postMessage("[proxy-worker] stacktrace.js loaded.");
+} catch (error) {
+  parentPort?.postMessage(
+    `[proxy-worker] Failed to read stacktrace.js: ${error.message}`,
+  );
+}
+try {
+  const dyadShimPath = path.join(__dirname, "dyad-shim.js");
+  dyadShimContent = fs.readFileSync(dyadShimPath, "utf-8");
+  parentPort?.postMessage("[proxy-worker] dyad-shim.js loaded.");
+} catch (error) {
+  parentPort?.postMessage(
+    `[proxy-worker] Failed to read dyad-shim.js: ${error.message}`,
+  );
+}
+/* ---------------------- helper: need to inject? ------------------------ */
+function needsInjection(pathname) {
+  return pathname.endsWith("index.html") || pathname === "/";
+}
+function injectHTML(buf) {
+  let txt = buf.toString("utf8");
+  // These are strings that were used since the first version of the dyad shim.
+  // If the dyad shim is used from legacy apps which came pre-baked with the shim
+  // as a vite plugin, then do not inject the shim twice to avoid weird behaviors.
+  if (txt.includes("window-error") && txt.includes("unhandled-rejection")) {
+    return buf;
+  }
+  const scripts = [];
+  if (stacktraceJsContent)
+    scripts.push(`<script>${stacktraceJsContent}</script>`);
+  else
+    scripts.push(
+      '<script>console.warn("[proxy-worker] stacktrace.js was not injected.");</script>',
+    );
+  if (dyadShimContent) scripts.push(`<script>${dyadShimContent}</script>`);
+  else
+    scripts.push(
+      '<script>console.warn("[proxy-worker] dyad shim was not injected.");</script>',
+    );
+  const allScripts = scripts.join("\n");
+  const headRegex = /<head[^>]*>/i;
+  if (headRegex.test(txt)) {
+    txt = txt.replace(headRegex, `$&\n${allScripts}`);
+  } else {
+    txt = allScripts + "\n" + txt;
+    parentPort?.postMessage(
+      "[proxy-worker] Warning: <head> tag not found – scripts prepended.",
+    );
+  }
+  return Buffer.from(txt, "utf8");
+}
+/* ---------------- helper: build upstream URL from request -------------- */
+function buildTargetURL(clientReq) {
+  // Support the old "?url=" mechanism
+  const parsedLocal = new URL(clientReq.url, `http://${LISTEN_HOST}`);
+  const urlParam = parsedLocal.searchParams.get("url");
+  if (urlParam) {
+    const abs = new URL(urlParam);
+    if (!/^https?:$/.test(abs.protocol))
+      throw new Error("only http/https targets allowed");
+    rememberedOrigin = abs.origin; // remember for later
+    return abs;
+  }
+  if (!rememberedOrigin)
+    throw new Error(
+      "No upstream configured. Use ?url=… once or set TARGET_URL env var.",
+    );
+  // Forward to the remembered origin keeping path & query
+  return new URL(clientReq.url, rememberedOrigin);
+}
+/* ----------------------------------------------------------------------- */
+/* 1. Plain HTTP request / response                                        */
+/* ----------------------------------------------------------------------- */
+const server = http.createServer((clientReq, clientRes) => {
+  let target;
+  try {
+    target = buildTargetURL(clientReq);
+  } catch (err) {
+    clientRes.writeHead(400, { "content-type": "text/plain" });
+    return void clientRes.end("Bad request: " + err.message);
+  }
+  const isTLS = target.protocol === "https:";
+  const lib = isTLS ? https : http;
+  /* Copy request headers but rewrite Host / Origin / Referer */
+  const headers = { ...clientReq.headers, host: target.host };
+  if (headers.origin) headers.origin = target.origin;
+  if (headers.referer) {
+    try {
+      const ref = new URL(headers.referer);
+      headers.referer = target.origin + ref.pathname + ref.search;
+    } catch {
+      delete headers.referer;
+    }
+  }
+  if (headers["if-none-match"] && needsInjection(target.pathname))
+    delete headers["if-none-match"];
+  const upOpts = {
+    protocol: target.protocol,
+    hostname: target.hostname,
+    port: target.port || (isTLS ? 443 : 80),
+    path: target.pathname + target.search,
+    method: clientReq.method,
+    headers,
+  };
+  const upReq = lib.request(upOpts, (upRes) => {
+    const inject = needsInjection(target.pathname);
+    if (!inject) {
+      clientRes.writeHead(upRes.statusCode, upRes.headers);
+      return void upRes.pipe(clientRes);
+    }
+    const chunks = [];
+    upRes.on("data", (c) => chunks.push(c));
+    upRes.on("end", () => {
+      try {
+        const merged = Buffer.concat(chunks);
+        const patched = injectHTML(merged);
+        const hdrs = {
+          ...upRes.headers,
+          "content-length": Buffer.byteLength(patched),
+        };
+        clientRes.writeHead(upRes.statusCode, hdrs);
+        clientRes.end(patched);
+      } catch (e) {
+        clientRes.writeHead(500, { "content-type": "text/plain" });
+        clientRes.end("Injection failed: " + e.message);
+      }
+    });
+  });
+  clientReq.pipe(upReq);
+  upReq.on("error", (e) => {
+    clientRes.writeHead(502, { "content-type": "text/plain" });
+    clientRes.end("Upstream error: " + e.message);
+  });
+});
+/* ----------------------------------------------------------------------- */
+/* 2. WebSocket / generic Upgrade tunnelling                               */
+/* ----------------------------------------------------------------------- */
+server.on("upgrade", (req, socket, _head) => {
+  let target;
+  try {
+    target = buildTargetURL(req);
+  } catch (err) {
+    socket.write("HTTP/1.1 400 Bad Request\r\n\r\n" + err.message);
+    return socket.destroy();
+  }
+  const isTLS = target.protocol === "https:";
+  const headers = { ...req.headers, host: target.host };
+  if (headers.origin) headers.origin = target.origin;
+  const upReq = (isTLS ? https : http).request({
+    protocol: target.protocol,
+    hostname: target.hostname,
+    port: target.port || (isTLS ? 443 : 80),
+    path: target.pathname + target.search,
+    method: "GET",
+    headers,
+  });
+  upReq.on("upgrade", (upRes, upSocket, upHead) => {
+    socket.write(
+      "HTTP/1.1 101 Switching Protocols\r\n" +
+        Object.entries(upRes.headers)
+          .map(([k, v]) => `${k}: ${v}`)
+          .join("\r\n") +
+        "\r\n\r\n",
+    );
+    if (upHead && upHead.length) socket.write(upHead);
+    upSocket.pipe(socket).pipe(upSocket);
+  });
+  upReq.on("error", () => socket.destroy());
+  upReq.end();
+});
+/* ----------------------------------------------------------------------- */
+server.listen(LISTEN_PORT, LISTEN_HOST, () => {
+  parentPort?.postMessage(
+    `proxy-server-start url=http://${LISTEN_HOST}:${LISTEN_PORT}`,
+  );
+});