diff --git a/types/p-defer/index.d.ts b/types/p-defer/index.d.ts
index 2b5e1ce56e..54ba6dd98b 100644
--- a/types/p-defer/index.d.ts
+++ b/types/p-defer/index.d.ts
@@ -3,12 +3,14 @@
 // Definitions by: Sam Verschueren <https://github.com/SamVerschueren>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 
-interface DeferredPromise<T> {
-	resolve<U>(value: U | PromiseLike<U>): Promise<U>;
-	reject(reason: any): Promise<never>;
-	promise: Promise<T>;
+declare namespace pDefer {
+	interface DeferredPromise<T> {
+		resolve<U>(value: U | PromiseLike<U>): Promise<U>;
+		reject(reason: any): Promise<never>;
+		promise: Promise<T>;
+	}
 }
 
-declare function pDefer<T>(): DeferredPromise<T>;
+declare function pDefer<T>(): pDefer.DeferredPromise<T>;
 
 export = pDefer;
diff --git a/types/p-defer/p-defer-tests.ts b/types/p-defer/p-defer-tests.ts
index 565c50e9dd..ad6c771590 100644
--- a/types/p-defer/p-defer-tests.ts
+++ b/types/p-defer/p-defer-tests.ts
@@ -1,10 +1,9 @@
 import pDefer = require('p-defer');
 
-function delay(ms: number) {
-    const deferred = pDefer<string>();
+function delay(deferred: pDefer.DeferredPromise<string>,  ms: number) {
     setTimeout(deferred.resolve, ms, '🦄');
     return deferred.promise;
 }
 
 let s: string;
-async function f() { s = await delay(100); }
+async function f() { s = await delay(pDefer<string>(), 100); }