diff --git a/package.json b/package.json
index 8f9420fb2..c3c12149e 100644
--- a/package.json
+++ b/package.json
@@ -41,7 +41,6 @@
   ],
   "dependencies": {
     "@babel/runtime": "^7.8.4",
-    "@sheerun/mutationobserver-shim": "^0.3.2",
     "@types/testing-library__dom": "^6.12.1",
     "aria-query": "^4.0.2",
     "dom-accessibility-api": "^0.3.0",
diff --git a/src/__tests__/helpers.js b/src/__tests__/helpers.js
index cbf6e6282..109fe1896 100644
--- a/src/__tests__/helpers.js
+++ b/src/__tests__/helpers.js
@@ -1,30 +1,5 @@
-import {getDocument, newMutationObserver} from '../helpers'
+import {getDocument} from '../helpers'
 
 test('returns global document if exists', () => {
   expect(getDocument()).toBe(document)
 })
-
-class DummyClass {
-  constructor(args) {
-    this.args = args
-  }
-}
-
-describe('newMutationObserver', () => {
-  if (typeof window === 'undefined') {
-    it('instantiates mock MutationObserver if not availble on window', () => {
-      expect(newMutationObserver(() => {}).observe).toBeDefined()
-    })
-  } else {
-    it('instantiates from global MutationObserver if available', () => {
-      const oldMutationObserver = window.MutationObserver
-      window.MutationObserver = DummyClass
-
-      try {
-        expect(newMutationObserver('foobar').args).toEqual('foobar')
-      } finally {
-        window.MutationObserver = oldMutationObserver
-      }
-    })
-  }
-})
diff --git a/src/events.js b/src/events.js
index 1bc3c6ffd..f6896c3c8 100644
--- a/src/events.js
+++ b/src/events.js
@@ -1,3 +1,4 @@
+import {getWindowFromNode} from './helpers'
 const eventMap = {
   // Clipboard Events
   copy: {
@@ -410,25 +411,6 @@ Object.keys(eventMap).forEach(key => {
   fireEvent[key] = (node, init) => fireEvent(node, createEvent[key](node, init))
 })
 
-function getWindowFromNode(node) {
-  // istanbul ignore next I'm not sure what could cause the final else so we'll leave it uncovered.
-  if (node.defaultView) {
-    // node is document
-    return node.defaultView
-  } else if (node.ownerDocument && node.ownerDocument.defaultView) {
-    // node is a DOM node
-    return node.ownerDocument.defaultView
-  } else if (node.window) {
-    // node is window
-    return node.window
-  } else {
-    // no idea...
-    throw new Error(
-      `Unable to find the "window" object for the given node. fireEvent currently supports firing events on DOM nodes, document, and window. Please file an issue with the code that's causing you to see this error: https://github.com/testing-library/dom-testing-library/issues/new`,
-    )
-  }
-}
-
 // function written after some investigation here:
 // https://github.com/facebook/react/issues/10135#issuecomment-401496776
 function setNativeValue(element, value) {
diff --git a/src/helpers.js b/src/helpers.js
index d12e5e85a..cc2321b33 100644
--- a/src/helpers.js
+++ b/src/helpers.js
@@ -1,5 +1,3 @@
-import MutationObserver from '@sheerun/mutationobserver-shim'
-
 const globalObj = typeof window === 'undefined' ? global : window
 
 // Currently this fn only supports jest timers, but it could support other test runners in the future.
@@ -41,16 +39,6 @@ const {clearTimeoutFn, setImmediateFn, setTimeoutFn} = runWithRealTimers(
   getTimeFunctions,
 )
 
-function newMutationObserver(onMutation) {
-  const MutationObserverConstructor =
-    typeof window !== 'undefined' &&
-    typeof window.MutationObserver !== 'undefined'
-      ? window.MutationObserver
-      : MutationObserver
-
-  return new MutationObserverConstructor(onMutation)
-}
-
 function getDocument() {
   /* istanbul ignore if */
   if (typeof window === 'undefined') {
@@ -58,10 +46,28 @@ function getDocument() {
   }
   return window.document
 }
+function getWindowFromNode(node) {
+  // istanbul ignore next I'm not sure what could cause the final else so we'll leave it uncovered.
+  if (node.defaultView) {
+    // node is document
+    return node.defaultView
+  } else if (node.ownerDocument && node.ownerDocument.defaultView) {
+    // node is a DOM node
+    return node.ownerDocument.defaultView
+  } else if (node.window) {
+    // node is window
+    return node.window
+  } else {
+    // no idea...
+    throw new Error(
+      `Unable to find the "window" object for the given node. Please file an issue with the code that's causing you to see this error: https://github.com/testing-library/dom-testing-library/issues/new`,
+    )
+  }
+}
 
 export {
+  getWindowFromNode,
   getDocument,
-  newMutationObserver,
   clearTimeoutFn as clearTimeout,
   setImmediateFn as setImmediate,
   setTimeoutFn as setTimeout,
diff --git a/src/wait-for-dom-change.js b/src/wait-for-dom-change.js
index 566746e1e..c3eec4cc4 100644
--- a/src/wait-for-dom-change.js
+++ b/src/wait-for-dom-change.js
@@ -1,5 +1,5 @@
 import {
-  newMutationObserver,
+  getWindowFromNode,
   getDocument,
   setImmediate,
   setTimeout,
@@ -31,7 +31,8 @@ function waitForDomChange({
   }
   return new Promise((resolve, reject) => {
     const timer = setTimeout(onTimeout, timeout)
-    const observer = newMutationObserver(onMutation)
+    const {MutationObserver} = getWindowFromNode(container)
+    const observer = new MutationObserver(onMutation)
     runWithRealTimers(() =>
       observer.observe(container, mutationObserverOptions),
     )
diff --git a/src/wait.js b/src/wait.js
index 86c7596d5..197ee1fb0 100644
--- a/src/wait.js
+++ b/src/wait.js
@@ -1,5 +1,5 @@
 import {
-  newMutationObserver,
+  getWindowFromNode,
   getDocument,
   setImmediate,
   setTimeout,
@@ -28,7 +28,8 @@ function wait(
     const overallTimeoutTimer = setTimeout(onTimeout, timeout)
     const intervalId = setInterval(checkCallback, interval)
 
-    const observer = newMutationObserver(checkCallback)
+    const {MutationObserver} = getWindowFromNode(container)
+    const observer = new MutationObserver(checkCallback)
     runWithRealTimers(() =>
       observer.observe(container, mutationObserverOptions),
     )