diff --git a/server/global.d.ts b/server/global.d.ts
new file mode 100644
index 0000000..ccd989a
--- /dev/null
+++ b/server/global.d.ts
@@ -0,0 +1,8 @@
+/* eslint-disable no-var */
+/* eslint-disable vars-on-top */
+export {};
+
+declare global {
+  var __DEV__: boolean;
+  var __DIFF__: boolean;
+}
\ No newline at end of file
diff --git a/server/src/server.ts b/server/src/server.ts
index c2b57e4..3afca83 100644
--- a/server/src/server.ts
+++ b/server/src/server.ts
@@ -225,7 +225,6 @@ async function lintMD(textDocument: TextDocument, range?: Range) {
 
 	const text = textDocument.getText(range);
 	try {
-		// FIXME: how to add expand globalThis with __DEV__ so that we do not need to set `"noImplicitAny": false` in tsconfig.json
 		// zhlint use globalThis.__DEV__ to control debug mode
 		globalThis.__DEV__ = settings.debug;
 		globalThis.__DIFF__ = settings.experimental.diff;
diff --git a/server/tsconfig.json b/server/tsconfig.json
index ed0ca32..fb5eb5e 100644
--- a/server/tsconfig.json
+++ b/server/tsconfig.json
@@ -8,8 +8,7 @@
 		"strict": true,
 		"outDir": "out",
 		"rootDir": "src",
-		"noImplicitAny": false
 	},
-	"include": ["src"],
+	"include": ["src", "global.d.ts"],
 	"exclude": ["node_modules", ".vscode-test"]
 }