diff --git a/package.json b/package.json
index 6813193..daa5646 100644
--- a/package.json
+++ b/package.json
@@ -5,8 +5,8 @@
   "type": "commonjs",
   "main": "dist/src/index.js",
   "scripts": {
-    "build": "tsc -p tsconfig.json && mkdir -p dist/web && cp web/index.html web/style.css dist/web/",
-    "typecheck": "tsc -p tsconfig.json --noEmit",
+    "build": "tsc -p tsconfig.json && tsc -p tsconfig.web.json && mkdir -p dist/web && cp web/index.html web/style.css dist/web/",
+    "typecheck": "tsc -p tsconfig.json --noEmit && tsc -p tsconfig.web.json --noEmit",
     "start": "npm run build && node dist/src/index.js",
     "test": "npm run build && STEAM_CHAT_DISABLE_AUTOSTART=1 node --test dist/test/*.test.js"
   },
diff --git a/test/web-build.test.ts b/test/web-build.test.ts
new file mode 100644
index 0000000..380253f
--- /dev/null
+++ b/test/web-build.test.ts
@@ -0,0 +1,13 @@
+'use strict';
+
+const assert = require('node:assert/strict');
+const fs = require('node:fs');
+const path = require('node:path');
+const test = require('node:test');
+
+test('web app build emits a browser-compatible script', () => {
+  const appPath = path.resolve(__dirname, '../web/app.js');
+  const appSource = fs.readFileSync(appPath, 'utf8');
+
+  assert.doesNotMatch(appSource, /\bexports\b|module\.exports|require\(/);
+});
diff --git a/tsconfig.json b/tsconfig.json
index 63eaa0a..b5deac7 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -13,5 +13,5 @@
     "noImplicitAny": true,
     "strict": false
   },
-  "include": ["src/**/*.ts", "test/**/*.ts", "web/**/*.ts"]
+  "include": ["src/**/*.ts", "test/**/*.ts"]
 }
diff --git a/tsconfig.web.json b/tsconfig.web.json
new file mode 100644
index 0000000..4eab0df
--- /dev/null
+++ b/tsconfig.web.json
@@ -0,0 +1,15 @@
+{
+  "compilerOptions": {
+    "target": "ES2022",
+    "module": "ES2022",
+    "rootDir": "web",
+    "outDir": "dist/web",
+    "lib": ["ES2022", "DOM", "DOM.Iterable"],
+    "types": [],
+    "forceConsistentCasingInFileNames": true,
+    "skipLibCheck": true,
+    "noImplicitAny": true,
+    "strict": false
+  },
+  "include": ["web/**/*.ts"]
+}