diff --git a/.vscode/settings.json b/.vscode/settings.json
index 7fef8b16..2c1653d3 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -2,6 +2,7 @@
   "chat.tools.terminal.autoApprove": {
     "npm run build": true,
     "npm run esbuild": true,
+    "npm run dev": true,
     "npm run lint": true,
     "npm run lint-fix": true,
     "npm run lint-api": true,
diff --git a/bin/esbuild.mjs b/bin/esbuild.mjs
index 1727defe..b1e9e88f 100644
--- a/bin/esbuild.mjs
+++ b/bin/esbuild.mjs
@@ -12,6 +12,7 @@ const config = {
   isProd: argv.includes('--prod'),
   isWatch: argv.includes('--watch'),
   isDemoClient: argv.includes('--demo-client'),
+  isDemoServer: argv.includes('--demo-server'),
   isHeadless: argv.includes('--headless'),
   addon: argv.find(e => e.startsWith('--addon='))?.replace(/^--addon=/, ''),
 };
@@ -126,7 +127,7 @@ if (config.addon) {
 } else if (config.isDemoClient) {
   bundleConfig = {
     ...bundleConfig,
-    entryPoints: [`demo/client.ts`],
+    entryPoints: [`demo/client/client.ts`],
     outfile: 'demo/dist/client-bundle.js',
     external: ['util', 'os', 'fs', 'path', 'stream', 'Terminal'],
     alias: {
@@ -152,6 +153,19 @@ if (config.addon) {
       "@xterm/addon-ligatures": "./addons/addon-ligatures/out-esbuild/LigaturesAddon",
     }
   }
+  skipOut = true;
+  skipOutTest = true;
+} else if (config.isDemoServer) {
+  bundleConfig = {
+    ...bundleConfig,
+    entryPoints: [`demo/server/server.ts`],
+    outfile: 'demo/dist/server-bundle.js',
+    format: 'cjs',
+    platform: 'node',
+    external: ['node-pty'],
+  }
+  skipOut = true;
+  skipOutTest = true;
 } else if (config.isHeadless) {
   bundleConfig = {
     ...bundleConfig,
diff --git a/demo/client.ts b/demo/client/client.ts
similarity index 100%
rename from demo/client.ts
rename to demo/client/client.ts
diff --git a/demo/components/controlBar.ts b/demo/client/components/controlBar.ts
similarity index 100%
rename from demo/components/controlBar.ts
rename to demo/client/components/controlBar.ts
diff --git a/demo/components/window/addonsWindow.ts b/demo/client/components/window/addonsWindow.ts
similarity index 100%
rename from demo/components/window/addonsWindow.ts
rename to demo/client/components/window/addonsWindow.ts
diff --git a/demo/components/window/baseWindow.ts b/demo/client/components/window/baseWindow.ts
similarity index 100%
rename from demo/components/window/baseWindow.ts
rename to demo/client/components/window/baseWindow.ts
diff --git a/demo/components/window/gpuWindow.ts b/demo/client/components/window/gpuWindow.ts
similarity index 100%
rename from demo/components/window/gpuWindow.ts
rename to demo/client/components/window/gpuWindow.ts
diff --git a/demo/components/window/optionsWindow.ts b/demo/client/components/window/optionsWindow.ts
similarity index 100%
rename from demo/components/window/optionsWindow.ts
rename to demo/client/components/window/optionsWindow.ts
diff --git a/demo/components/window/styleWindow.ts b/demo/client/components/window/styleWindow.ts
similarity index 100%
rename from demo/components/window/styleWindow.ts
rename to demo/client/components/window/styleWindow.ts
diff --git a/demo/components/window/testWindow.ts b/demo/client/components/window/testWindow.ts
similarity index 99%
rename from demo/components/window/testWindow.ts
rename to demo/client/components/window/testWindow.ts
index 99efbad4..bb542595 100644
--- a/demo/components/window/testWindow.ts
+++ b/demo/client/components/window/testWindow.ts
@@ -3,9 +3,9 @@
  * @license MIT
  */
 
-/// <reference path="../../../typings/xterm.d.ts"/>
+/// <reference path="../../../../typings/xterm.d.ts"/>
 
-import { writeUnicodeTable } from 'unicodeTable';
+import { writeUnicodeTable } from '../../unicodeTable';
 import type { IControlWindow } from '../controlBar';
 import { BaseWindow } from './baseWindow';
 import type { IDisposable, Terminal } from '@xterm/xterm';
diff --git a/demo/components/window/vtWindow.ts b/demo/client/components/window/vtWindow.ts
similarity index 100%
rename from demo/components/window/vtWindow.ts
rename to demo/client/components/window/vtWindow.ts
diff --git a/demo/client/tsconfig.json b/demo/client/tsconfig.json
new file mode 100644
index 00000000..7676cd37
--- /dev/null
+++ b/demo/client/tsconfig.json
@@ -0,0 +1,27 @@
+{
+  "compilerOptions": {
+    "module": "commonjs",
+    "target": "es2021",
+    "rootDir": ".",
+    "sourceMap": true,
+    "baseUrl": ".",
+    "paths": {
+      "@xterm/addon-attach": ["../../addons/addon-attach"],
+      "@xterm/addon-clipboard": ["../../addons/addon-clipboard"],
+      "@xterm/addon-fit": ["../../addons/addon-fit"],
+      "@xterm/addon-image": ["../../addons/addon-image"],
+      "@xterm/addon-progress": ["../../addons/addon-progress"],
+      "@xterm/addon-search": ["../../addons/addon-search"],
+      "@xterm/addon-serialize": ["../../addons/addon-serialize"],
+      "@xterm/addon-web-links": ["../../addons/addon-web-links"],
+      "@xterm/addon-webgl": ["../../addons/addon-webgl"],
+      "@xterm/addon-unicode11": ["../../addons/addon-unicode11"],
+      "@xterm/addon-unicode-graphemes": ["../../addons/addon-unicode-graphemes"],
+      "@xterm/addon-ligatures": ["../../addons/addon-ligatures"]
+    }
+  },
+  "include": [
+    "client.ts",
+    "../../typings/xterm.d.ts"
+  ]
+}
diff --git a/demo/unicodeTable.ts b/demo/client/unicodeTable.ts
similarity index 100%
rename from demo/unicodeTable.ts
rename to demo/client/unicodeTable.ts
diff --git a/demo/server.js b/demo/server/server.ts
similarity index 78%
rename from demo/server.js
rename to demo/server/server.ts
index 4537d501..cefb343e 100644
--- a/demo/server.js
+++ b/demo/server/server.ts
@@ -4,54 +4,58 @@
  * demo to the public as is would introduce security risks for the host.
  **/
 
-// @ts-check
+import * as express from 'express';
+import * as expressWs from 'express-ws';
+import * as os from 'os';
+import * as pty from 'node-pty';
+import * as path from 'path';
+import type { IPty } from 'node-pty';
 
-const express = require('express');
-const expressWs = require('express-ws');
-const os = require('os');
-const pty = require('node-pty');
+interface IDisposable {
+  dispose(): void;
+}
 
 /** Whether to use binary transport. */
 const USE_BINARY = os.platform() !== "win32";
 
-function startServer() {
+const demoRoot = path.join(__dirname, '..');
+
+function startServer(): void {
   const app = express();
   const appWs = expressWs(app).app;
 
-  const terminals = {};
-  const unsentOutput = {};
-  const temporaryDisposable = {};
+  const terminals: { [pid: number]: IPty } = {};
+  const unsentOutput: { [pid: number]: string } = {};
+  const temporaryDisposable: { [pid: number]: IDisposable } = {};
 
-  app.use('/xterm.css', express.static(__dirname + '/../css/xterm.css'));
+  app.use('/xterm.css', express.static(demoRoot + '/../css/xterm.css'));
   app.get('/logo.png', (req, res) => {
-    res.sendFile(__dirname + '/logo.png');
+    res.sendFile(demoRoot + '/logo.png');
   });
 
   app.get('/', (req, res) => {
-    res.sendFile(__dirname + '/index.html');
+    res.sendFile(demoRoot + '/index.html');
   });
 
   app.get('/test', (req, res) => {
-    res.sendFile(__dirname + '/test.html');
+    res.sendFile(demoRoot + '/test.html');
   });
 
   app.get('/index.css', (req, res) => {
-    res.sendFile(__dirname + '/index.css');
+    res.sendFile(demoRoot + '/index.css');
   });
 
-  app.use('/dist', express.static(__dirname + '/dist'));
-  app.use('/src', express.static(__dirname + '/src'));
+  app.use('/dist', express.static(demoRoot + '/dist'));
+  app.use('/src', express.static(demoRoot + '/src'));
 
   app.post('/terminals', (req, res) => {
-    /** @type {{ [key: string]: string }} */
-    const env = {};
+    const env: { [key: string]: string } = {};
     for (const k of Object.keys(process.env)) {
       const v = process.env[k];
       if (v) {
         env[k] = v;
       }
     }
-    // const env = Object.assign({}, process.env);
     env['COLORTERM'] = 'truecolor';
     if (typeof req.query.cols !== 'string' || typeof req.query.rows !== 'string') {
       console.error({ req });
@@ -108,10 +112,10 @@ function startServer() {
     let userInput = false;
 
     // string message buffering
-    function buffer(socket, timeout, maxSize) {
+    function buffer(socket: typeof ws, timeout: number, maxSize: number) {
       let s = '';
-      let sender = null;
-      return (data) => {
+      let sender: ReturnType<typeof setTimeout> | null = null;
+      return (data: string) => {
         s += data;
         if (s.length > maxSize || userInput) {
           userInput = false;
@@ -131,11 +135,11 @@ function startServer() {
       };
     }
     // binary message buffering
-    function bufferUtf8(socket, timeout, maxSize) {
-      const chunks = [];
+    function bufferUtf8(socket: typeof ws, timeout: number, maxSize: number) {
+      const chunks: Buffer[] = [];
       let length = 0;
-      let sender = null;
-      return (data) => {
+      let sender: ReturnType<typeof setTimeout> | null = null;
+      return (data: Buffer) => {
         chunks.push(data);
         length += data.length;
         if (length > maxSize || userInput) {
@@ -164,13 +168,13 @@ function startServer() {
     // the problem and how to implement flow control at https://xtermjs.org/docs/guides/flowcontrol/
     term.onData(function(data) {
       try {
-        send(data);
+        send(data as string & Buffer);
       } catch (ex) {
         // The WebSocket is not open, ignore
       }
     });
     ws.on('message', function(msg) {
-      term.write(msg);
+      term.write(msg.toString());
       userInput = true;
     });
     ws.on('close', function () {
@@ -196,4 +200,4 @@ process.on('uncaughtException', (error) => {
   }
 });
 
-module.exports = startServer;
+export default startServer;
diff --git a/demo/server/tsconfig.json b/demo/server/tsconfig.json
new file mode 100644
index 00000000..ed5c6a90
--- /dev/null
+++ b/demo/server/tsconfig.json
@@ -0,0 +1,11 @@
+{
+  "compilerOptions": {
+    "module": "commonjs",
+    "target": "es2021",
+    "rootDir": ".",
+    "sourceMap": true
+  },
+  "include": [
+    "server.ts"
+  ]
+}
diff --git a/demo/start.js b/demo/start.js
index b240966f..08f9c059 100644
--- a/demo/start.js
+++ b/demo/start.js
@@ -5,6 +5,6 @@
 
 // @ts-check
 
-const startServer = require('./server.js');
+const startServer = require('./dist/server-bundle.js').default;
 
 startServer();
diff --git a/demo/tsconfig.json b/demo/tsconfig.json
index 405dbf0f..e9e26053 100644
--- a/demo/tsconfig.json
+++ b/demo/tsconfig.json
@@ -1,27 +1,7 @@
 {
-  "compilerOptions": {
-    "module": "commonjs",
-    "target": "es2021",
-    "rootDir": ".",
-    "sourceMap": true,
-    "baseUrl": ".",
-    "paths": {
-      "@xterm/addon-attach": ["../addons/addon-attach"],
-      "@xterm/addon-clipboard": ["../addons/addon-clipboard"],
-      "@xterm/addon-fit": ["../addons/addon-fit"],
-      "@xterm/addon-image": ["../addons/addon-image"],
-      "@xterm/addon-progress": ["../addons/addon-progress"],
-      "@xterm/addon-search": ["../addons/addon-search"],
-      "@xterm/addon-serialize": ["../addons/addon-serialize"],
-      "@xterm/addon-web-links": ["../addons/addon-web-links"],
-      "@xterm/addon-webgl": ["../addons/addon-webgl"],
-      "@xterm/addon-unicode11": ["../addons/addon-unicode11"],
-      "@xterm/addon-unicode-graphemes": ["../addons/addon-unicode-graphemes"],
-      "@xterm/addon-ligatures": ["../addons/addon-ligatures"]
-    }
-  },
-  "include": [
-    "client.ts",
-    "../typings/xterm.d.ts"
-  ]
+  "references": [
+    { "path": "./client" },
+    { "path": "./server" }
+  ],
+  "files": []
 }