diff --git a/packages/material-ui-styles/src/defaultTheme/defaultTheme.spec.ts b/packages/material-ui-styles/src/defaultTheme/defaultTheme.spec.ts
index 96a7b2142e5237..6bc4c5ddd2eb4c 100644
--- a/packages/material-ui-styles/src/defaultTheme/defaultTheme.spec.ts
+++ b/packages/material-ui-styles/src/defaultTheme/defaultTheme.spec.ts
@@ -13,7 +13,7 @@ declare module '@material-ui/styles' {
 }
 
 {
-  makeStyles(theme => {
+  makeStyles((theme) => {
     // $ExpectType string
     const value = theme.myProperty;
 
diff --git a/packages/material-ui/src/styles/createMixins.spec.ts b/packages/material-ui/src/styles/createMixins.spec.ts
index 91e3e0292cb6fe..0564d0fdab7ae1 100644
--- a/packages/material-ui/src/styles/createMixins.spec.ts
+++ b/packages/material-ui/src/styles/createMixins.spec.ts
@@ -1,29 +1,29 @@
 import { createMuiTheme, makeStyles } from '@material-ui/core/styles';
 
 {
-   const theme = createMuiTheme({
-        mixins: {
-            toolbar: {
-                background: '#fff',
-                minHeight: 36,
-                '@media (min-width:0px) and (orientation: landscape)': {
-                    minHeight: 24
-                },
-                '@media (min-width:600px)': {
-                    minHeight: 48
-                }
-            },
-        }
-    });
-
-    const useStyles = makeStyles(theme => ({
-        appBarSpacer: theme.mixins.toolbar,
-        toolbarIcon: {
-            display: 'flex',
-            alignItems: 'center',
-            justifyContent: 'flex-end',
-            padding: '0 8px',
-            ...theme.mixins.toolbar,
+  const theme = createMuiTheme({
+    mixins: {
+      toolbar: {
+        background: '#fff',
+        minHeight: 36,
+        '@media (min-width:0px) and (orientation: landscape)': {
+          minHeight: 24,
+        },
+        '@media (min-width:600px)': {
+          minHeight: 48,
         },
-    }));
+      },
+    },
+  });
+
+  const useStyles = makeStyles((theme) => ({
+    appBarSpacer: theme.mixins.toolbar,
+    toolbarIcon: {
+      display: 'flex',
+      alignItems: 'center',
+      justifyContent: 'flex-end',
+      padding: '0 8px',
+      ...theme.mixins.toolbar,
+    },
+  }));
 }
diff --git a/packages/material-ui/test/typescript/colors.spec.ts b/packages/material-ui/test/typescript/colors.spec.ts
index 8c24ba74d1c59b..45058f5bc42022 100644
--- a/packages/material-ui/test/typescript/colors.spec.ts
+++ b/packages/material-ui/test/typescript/colors.spec.ts
@@ -1,13 +1,26 @@
 import { colors, Color } from '@material-ui/core';
 
 const {
-  amber, blue, blueGrey,
-  brown, cyan, deepOrange,
-  deepPurple, green, grey,
-  indigo, lightBlue, lightGreen,
-  lime, orange, pink,
-  purple, red, teal,
-  yellow, common
+  amber,
+  blue,
+  blueGrey,
+  brown,
+  cyan,
+  deepOrange,
+  deepPurple,
+  green,
+  grey,
+  indigo,
+  lightBlue,
+  lightGreen,
+  lime,
+  orange,
+  pink,
+  purple,
+  red,
+  teal,
+  yellow,
+  common,
 } = colors;
 
 const colorList: Color[] = [
diff --git a/scripts/generateProptypes.ts b/scripts/generateProptypes.ts
index e92ac892467e7b..7926bafad120c8 100644
--- a/scripts/generateProptypes.ts
+++ b/scripts/generateProptypes.ts
@@ -43,8 +43,8 @@ async function generateProptypes(
     return GenerateResult.NoComponent;
   }
 
-  proptypes.body.forEach(component => {
-    component.types.forEach(prop => {
+  proptypes.body.forEach((component) => {
+    component.types.forEach((prop) => {
       if (prop.name === 'classes' && prop.jsDoc) {
         prop.jsDoc += '\nSee [CSS API](#css) below for more details.';
       } else if (prop.name === 'children' && !prop.jsDoc) {
@@ -100,7 +100,7 @@ async function run() {
     [
       path.resolve(__dirname, '../packages/material-ui/src'),
       path.resolve(__dirname, '../packages/material-ui-lab/src'),
-    ].map(folderPath =>
+    ].map((folderPath) =>
       glob('+([A-Z])*/+([A-Z])*.d.ts', {
         absolute: true,
         cwd: folderPath,
@@ -111,7 +111,7 @@ async function run() {
   const files = _.flatten(allFiles)
     // Filter out files where the directory name and filename doesn't match
     // Example: Modal/ModalManager.d.ts
-    .filter(filePath => {
+    .filter((filePath) => {
       const folderName = path.basename(path.dirname(filePath));
       const fileName = path.basename(filePath, '.d.ts');
 
@@ -120,7 +120,7 @@ async function run() {
 
   const program = ttp.createProgram(files, tsconfig);
 
-  const promises = files.map<Promise<GenerateResult>>(async tsFile => {
+  const promises = files.map<Promise<GenerateResult>>(async (tsFile) => {
     const jsFile = tsFile.replace('.d.ts', '.js');
 
     if (!ignoreCache && (await fse.stat(jsFile)).mtimeMs > (await fse.stat(tsFile)).mtimeMs) {
@@ -140,7 +140,7 @@ async function run() {
   }
 
   console.log('--- Summary ---');
-  const groups = _.groupBy(results, x => x);
+  const groups = _.groupBy(results, (x) => x);
 
   _.forOwn(groups, (count, key) => {
     console.log('%s: %d', GenerateResult[(key as unknown) as GenerateResult], count.length);
@@ -149,7 +149,7 @@ async function run() {
   console.log('Total: %d', results.length);
 }
 
-run().catch(error => {
+run().catch((error) => {
   console.error(error);
   process.exit(1);
 });
diff --git a/scripts/prettier.js b/scripts/prettier.js
index 2b38897360fe7e..37beae02144615 100644
--- a/scripts/prettier.js
+++ b/scripts/prettier.js
@@ -24,7 +24,7 @@ function runPrettier(options) {
     .filter((notEmpty) => notEmpty);
 
   const files = glob
-    .sync('**/*.{js,tsx,d.ts}', { ignore: ['**/node_modules/**', ...ignoredFiles] })
+    .sync('**/*.{js,tsx,ts}', { ignore: ['**/node_modules/**', ...ignoredFiles] })
     .filter((f) => !changedFiles || changedFiles.has(f));
 
   if (!files.length) {