diff --git a/index.d.ts b/index.d.ts
new file mode 100644
index 0000000..7a834c4
--- /dev/null
+++ b/index.d.ts
@@ -0,0 +1,60 @@
+/// <reference types="node" />
+
+import { IncomingHttpHeaders } from "http";
+
+type StaticOrigin = boolean | string | RegExp | Array<boolean | string | RegExp>;
+
+type CustomOrigin = (
+    requestOrigin: string | undefined,
+    callback: (err: Error | null, origin?: StaticOrigin) => void,
+) => void;
+
+declare namespace e {
+    interface CorsRequest {
+        method?: string | undefined;
+        headers: IncomingHttpHeaders;
+    }
+    interface CorsOptions {
+        /**
+         * @default '*'
+         */
+        origin?: StaticOrigin | CustomOrigin | undefined;
+        /**
+         * @default 'GET,HEAD,PUT,PATCH,POST,DELETE'
+         */
+        methods?: string | string[] | undefined;
+        /**
+         * @deprecated Use `allowedHeaders` instead.
+         */
+        headers?: string | string[] | undefined;
+        allowedHeaders?: string | string[] | undefined;
+        exposedHeaders?: string | string[] | undefined;
+        credentials?: boolean | undefined;
+        maxAge?: number | undefined;
+        /**
+         * @default false
+         */
+        preflightContinue?: boolean | undefined;
+        /**
+         * @default 204
+         */
+        optionsSuccessStatus?: number | undefined;
+    }
+    type CorsOptionsDelegate<T extends CorsRequest = CorsRequest> = (
+        req: T,
+        callback: (err: Error | null, options?: CorsOptions) => void,
+    ) => void;
+}
+
+declare function e<T extends e.CorsRequest = e.CorsRequest>(
+    options?: e.CorsOptions | e.CorsOptionsDelegate<T>,
+): (
+    req: T,
+    res: {
+        statusCode?: number | undefined;
+        setHeader(key: string, value: string): any;
+        end(): any;
+    },
+    next: (err?: any) => any,
+) => void;
+export = e;
diff --git a/package.json b/package.json
index e90bac8..660ab7c 100644
--- a/package.json
+++ b/package.json
@@ -16,6 +16,7 @@
     "url": "https://opencollective.com/express"
   },
   "main": "./lib/index.js",
+  "types": "./index.d.ts",
   "dependencies": {
     "object-assign": "^4",
     "vary": "^1"
@@ -29,6 +30,7 @@
     "supertest": "6.1.3"
   },
   "files": [
+    "index.d.ts",
     "lib/index.js"
   ],
   "engines": {