diff --git a/src/resolvers/create.ts b/src/resolvers/create.ts
index fc771012a..c74871891 100644
--- a/src/resolvers/create.ts
+++ b/src/resolvers/create.ts
@@ -9,7 +9,7 @@ import { getParams, applyMiddlewares, applyAuthChecker } from "./helpers";
 import { convertToType } from "../helpers/types";
 import { BuildContext } from "../schema/build-context";
 import { ResolverData } from "../interfaces";
-import { isPromise } from "../utils";
+import isPromiseLike from "../utils/isPromiseLike";
 
 export function createHandlerResolver(
   resolverMetadata: BaseResolverMetadata,
@@ -35,7 +35,7 @@ export function createHandlerResolver(
         globalValidate,
         pubSub,
       );
-      if (isPromise(params)) {
+      if (isPromiseLike(params)) {
         return params.then(resolvedParams =>
           targetInstance[resolverMetadata.methodName].apply(targetInstance, resolvedParams),
         );
diff --git a/src/resolvers/helpers.ts b/src/resolvers/helpers.ts
index 7bdf5e767..b3893e0ba 100644
--- a/src/resolvers/helpers.ts
+++ b/src/resolvers/helpers.ts
@@ -9,7 +9,7 @@ import { Middleware, MiddlewareFn, MiddlewareClass } from "../interfaces/Middlew
 import { IOCContainer } from "../utils/container";
 import { AuthMiddleware } from "../helpers/auth-middleware";
 import { convertArgsToInstance, convertArgToInstance } from "./convert-args";
-import { isPromise } from "../utils/isPromise";
+import isPromiseLike from "../utils/isPromiseLike";
 
 export function getParams(
   params: ParamMetadata[],
@@ -57,7 +57,7 @@ export function getParams(
           return paramInfo.resolver(resolverData);
       }
     });
-  if (paramValues.some(isPromise)) {
+  if (paramValues.some(isPromiseLike)) {
     return Promise.all(paramValues);
   } else {
     return paramValues;
diff --git a/src/utils/index.ts b/src/utils/index.ts
index 5b89e41fc..ae0474d9b 100644
--- a/src/utils/index.ts
+++ b/src/utils/index.ts
@@ -7,4 +7,3 @@ export {
   defaultPrintSchemaOptions,
 } from "./emitSchemaDefinitionFile";
 export { ContainerType, ContainerGetter } from "./container";
-export { isPromise } from "./isPromise";
diff --git a/src/utils/isPromise.ts b/src/utils/isPromise.ts
deleted file mode 100644
index a97644669..000000000
--- a/src/utils/isPromise.ts
+++ /dev/null
@@ -1,3 +0,0 @@
-export function isPromise<T>(value: PromiseLike<T> | T): value is PromiseLike<T> {
-  return Boolean(value && typeof (value as any).then === "function");
-}
diff --git a/src/utils/isPromiseLike.ts b/src/utils/isPromiseLike.ts
new file mode 100644
index 000000000..1a9743f3b
--- /dev/null
+++ b/src/utils/isPromiseLike.ts
@@ -0,0 +1,5 @@
+export default function isPromiseLike<TValue>(
+  value: PromiseLike<TValue> | TValue,
+): value is PromiseLike<TValue> {
+  return value != null && typeof (value as PromiseLike<TValue>).then === "function";
+}