diff --git a/__tests__/index.test.js b/__tests__/index.test.js
index 4ae1ace..91a49e8 100644
--- a/__tests__/index.test.js
+++ b/__tests__/index.test.js
@@ -7,6 +7,7 @@ const flushPromises = () => new Promise(setImmediate);
 
 Platform.OS = 'android';
 
+// @ts-ignore
 AppRegistry.registerHeadlessTask = jest.fn(async (taskName, task) => task()());
 
 const defaultOptions = {
@@ -33,9 +34,11 @@ test('stop-empty', async () => {
 test('start-android', async () => {
     let promiseFinish = () => {};
     const defaultTask = jest.fn(
+        // @ts-ignore
         async () => await new Promise((resolve) => (promiseFinish = resolve))
     );
     Platform.OS = 'android';
+    // @ts-ignore
     AppRegistry.registerHeadlessTask.mockClear();
     RNBackgroundActionsModule.start.mockClear();
     await BackgroundActions.start(defaultTask, defaultOptions);
@@ -52,8 +55,10 @@ test('start-android', async () => {
 test('start-ios', async () => {
     let promiseFinish = () => {};
     const defaultTask = jest.fn(
+        // @ts-ignore
         async () => await new Promise((resolve) => (promiseFinish = resolve))
     );
+    // @ts-ignore
     AppRegistry.registerHeadlessTask.mockClear();
     Platform.OS = 'ios';
     RNBackgroundActionsModule.start.mockClear();
@@ -71,6 +76,7 @@ test('start-ios', async () => {
 test('stop', async () => {
     let promiseFinish = () => {};
     const defaultTask = jest.fn(
+        // @ts-ignore
         async () => await new Promise((resolve) => (promiseFinish = resolve))
     );
     await BackgroundActions.start(defaultTask, defaultOptions);
@@ -85,6 +91,7 @@ test('updateNotification-ios', async () => {
     Platform.OS = 'ios';
     let promiseFinish = () => {};
     const defaultTask = jest.fn(
+        // @ts-ignore
         async () => await new Promise((resolve) => (promiseFinish = resolve))
     );
     await BackgroundActions.start(defaultTask, defaultOptions);
@@ -98,6 +105,7 @@ test('updateNotification-android', async () => {
     Platform.OS = 'android';
     let promiseFinish = () => {};
     const defaultTask = jest.fn(
+        // @ts-ignore
         async () => await new Promise((resolve) => (promiseFinish = resolve))
     );
     await BackgroundActions.start(defaultTask, defaultOptions);
diff --git a/package.json b/package.json
index be5a69c..fd03541 100644
--- a/package.json
+++ b/package.json
@@ -69,7 +69,7 @@
     "react": "16.9.0",
     "react-native": "^0.61.4",
     "semantic-release": "^17.0.1",
-    "typescript": "^3.8.2"
+    "typescript": "4.0.3"
   },
   "dependencies": {}
 }
diff --git a/yarn.lock b/yarn.lock
index 2c247b2..e167532 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -8876,10 +8876,10 @@ typedarray@^0.0.6:
   resolved "https://registry.yarnpkg.com/typedarray/-/typedarray-0.0.6.tgz#867ac74e3864187b1d3d47d996a78ec5c8830777"
   integrity sha1-hnrHTjhkGHsdPUfZlqeOxciDB3c=
 
-typescript@^3.8.2:
-  version "3.8.2"
-  resolved "https://registry.yarnpkg.com/typescript/-/typescript-3.8.2.tgz#91d6868aaead7da74f493c553aeff76c0c0b1d5a"
-  integrity sha512-EgOVgL/4xfVrCMbhYKUQTdF37SQn4Iw73H5BgCrF1Abdun7Kwy/QZsE/ssAy0y4LxBbvua3PIbFsbRczWWnDdQ==
+typescript@4.0.3:
+  version "4.0.3"
+  resolved "https://registry.yarnpkg.com/typescript/-/typescript-4.0.3.tgz#153bbd468ef07725c1df9c77e8b453f8d36abba5"
+  integrity sha512-tEu6DGxGgRJPb/mVPIZ48e69xCn2yRmCgYmDugAVwmJ6o+0u1RI18eO7E7WBTLYLaEVVOhwQmcdhQHweux/WPg==
 
 ua-parser-js@^0.7.18:
   version "0.7.21"