diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 5d93fd1..9805e7e 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -26,5 +26,6 @@ jobs:
 
       - run: pnpm install --frozen-lockfile
       - run: pnpm compile
+      - run: pnpm typecheck
       - run: pnpm lint
       - run: pnpm test
diff --git a/package.json b/package.json
index 95f0e17..228ad3b 100644
--- a/package.json
+++ b/package.json
@@ -149,6 +149,7 @@
     "compile": "tsup ./src/extension.ts --external vscode --minify",
     "watch": "tsup ./src/extension.ts --external vscode --watch --sourcemap",
     "test": "vitest run --config vite.global-config.ts",
+    "typecheck": "tsc --noEmit",
     "lint": "eslint --cache .",
     "lint:fix": "eslint --cache --fix ."
   },
diff --git a/src/pure/watch/ws-client.ts b/src/pure/watch/ws-client.ts
index 1ec1301..e65d529 100644
--- a/src/pure/watch/ws-client.ts
+++ b/src/pure/watch/ws-client.ts
@@ -4,6 +4,7 @@ import { shallowReactive } from '@vue/reactivity'
 import type { BirpcReturn } from 'birpc'
 import { createBirpc } from 'birpc'
 import { parse, stringify } from 'flatted'
+import WebSocket from 'ws'
 
 import type {
   File,
@@ -114,7 +115,7 @@ export function createClient(url: string, options: VitestClientOptions = {}) {
     reconnectInterval = 2000,
     reconnectTries = 10,
     reactive = v => v,
-    WebSocketConstructor = globalThis.WebSocket,
+    WebSocketConstructor = WebSocket,
     onFailedConnection,
   } = options
 
diff --git a/tsconfig.json b/tsconfig.json
index 6e34250..f161b0b 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -1,18 +1,15 @@
 {
   "compilerOptions": {
     "target": "ES2020",
-    "lib": ["ES2020", "ESNext.Disposable", "DOM"],
+    "lib": ["ES2020", "ESNext.Disposable"],
     "rootDir": "src",
     "module": "commonJS",
+    "types": ["node"],
     "strict": true,
     "outDir": "out",
     "sourceMap": true,
     "esModuleInterop": true,
-    "skipLibCheck": true /* enable all strict type-checking options */
-    /* Additional Checks */
-    // "noImplicitReturns": true, /* Report error when not all code paths in function return a value. */
-    // "noFallthroughCasesInSwitch": true, /* Report errors for fallthrough cases in switch statement. */
-    // "noUnusedParameters": true,  /* Report errors on unused parameters. */
+    "skipLibCheck": true
   },
   "include": ["src/**/*.ts"],
   "exclude": ["samples/**/*"]