diff --git a/packages/react-art/src/ReactARTHostConfig.js b/packages/react-art/src/ReactARTHostConfig.js
index ad2d73062240e..703d2c21c679d 100644
--- a/packages/react-art/src/ReactARTHostConfig.js
+++ b/packages/react-art/src/ReactARTHostConfig.js
@@ -330,7 +330,7 @@ export function getChildHostContext() {
 export const scheduleTimeout = setTimeout;
 export const cancelTimeout = clearTimeout;
 export const noTimeout = -1;
-export function queueMicrotask() {
+export function queueMicrotask(callback: Function) {
   invariant(false, 'Not implemented.');
 }
 
diff --git a/packages/react-dom/src/client/ReactDOMHostConfig.js b/packages/react-dom/src/client/ReactDOMHostConfig.js
index c0f0c52fdbb86..969f6f88b02a6 100644
--- a/packages/react-dom/src/client/ReactDOMHostConfig.js
+++ b/packages/react-dom/src/client/ReactDOMHostConfig.js
@@ -384,9 +384,9 @@ export const scheduleTimeout: any =
 export const cancelTimeout: any =
   typeof clearTimeout === 'function' ? clearTimeout : (undefined: any);
 export const noTimeout = -1;
-export const queueMicrotask: (Function => void) | undefined =
-  typeof queueMicrotask === 'function'
-    ? queueMicrotask
+export const queueMicrotask: any =
+  typeof global.queueMicrotask === 'function'
+    ? global.queueMicrotask
     : typeof Promise !== 'undefined'
     ? callback =>
         Promise.resolve(null)
diff --git a/packages/react-native-renderer/src/ReactFabricHostConfig.js b/packages/react-native-renderer/src/ReactFabricHostConfig.js
index a960f26c5fd0a..7329a5f04a043 100644
--- a/packages/react-native-renderer/src/ReactFabricHostConfig.js
+++ b/packages/react-native-renderer/src/ReactFabricHostConfig.js
@@ -348,7 +348,7 @@ export const warnsIfNotActing = false;
 export const scheduleTimeout = setTimeout;
 export const cancelTimeout = clearTimeout;
 export const noTimeout = -1;
-export function queueMicrotask() {
+export function queueMicrotask(callback: Function) {
   invariant(false, 'Not implemented.');
 }
 
diff --git a/packages/react-native-renderer/src/ReactNativeHostConfig.js b/packages/react-native-renderer/src/ReactNativeHostConfig.js
index 69cb665d26d03..5f64845f31421 100644
--- a/packages/react-native-renderer/src/ReactNativeHostConfig.js
+++ b/packages/react-native-renderer/src/ReactNativeHostConfig.js
@@ -247,7 +247,7 @@ export const warnsIfNotActing = true;
 export const scheduleTimeout = setTimeout;
 export const cancelTimeout = clearTimeout;
 export const noTimeout = -1;
-export function queueMicrotask() {
+export function queueMicrotask(callback: Function) {
   invariant(false, 'Not implemented.');
 }