diff --git a/.eslintrc.js b/.eslintrc.js
index 8167affbdb..993d1d1e19 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -90,6 +90,7 @@ module.exports = {
     ],
     'no-unused-vars': OFF,
     'no-nested-ternary': WARNING,
+    '@typescript-eslint/no-empty-function': OFF,
     '@typescript-eslint/no-unused-vars': [ERROR, {argsIgnorePattern: '^_'}],
     '@typescript-eslint/ban-ts-comment': [
       ERROR,
@@ -108,7 +109,6 @@ module.exports = {
     camelcase: WARNING,
     'no-restricted-syntax': WARNING,
     'no-unused-expressions': WARNING,
-    '@typescript-eslint/no-empty-function': WARNING,
     'global-require': WARNING,
     'prefer-destructuring': WARNING,
     yoda: WARNING,
diff --git a/packages/docusaurus-migrate/src/__tests__/migrationConfig.test.ts b/packages/docusaurus-migrate/src/__tests__/migrationConfig.test.ts
index 9acf2f5abc..abbbd38488 100644
--- a/packages/docusaurus-migrate/src/__tests__/migrationConfig.test.ts
+++ b/packages/docusaurus-migrate/src/__tests__/migrationConfig.test.ts
@@ -13,7 +13,7 @@ describe('create config', () => {
   test('simple test', () => {
     const v1Config: VersionOneConfig = importFresh(
       `${__dirname}/__fixtures__/sourceSiteConfig.js`,
-    ) as any;
+    );
     const siteDir = 'website';
     const newDir = 'websiteMigrated';
 
diff --git a/packages/docusaurus-migrate/src/types.ts b/packages/docusaurus-migrate/src/types.ts
index 0f18ae25d1..2aee8990ec 100644
--- a/packages/docusaurus-migrate/src/types.ts
+++ b/packages/docusaurus-migrate/src/types.ts
@@ -16,9 +16,9 @@ export type Data = {
 };
 
 export type ClassicPresetEntries = {
-  docs: {[key: string]: any};
-  blog: {[key: string]: any};
-  theme: {[key: string]: any};
+  docs: {[key: string]: unknown};
+  blog: {[key: string]: unknown};
+  theme: {[key: string]: unknown};
 };
 
 export type SidebarEntries = {
@@ -39,7 +39,7 @@ export interface VersionTwoConfig {
   githubHost?: string;
   onBrokenLinks: string;
   onBrokenMarkdownLinks: string;
-  plugins: Array<[string, {[key: string]: any}]>;
+  plugins: Array<[string, {[key: string]: unknown}]>;
   themes?: [];
   presets: [[string, ClassicPresetEntries]];
   themeConfig: {
@@ -114,8 +114,8 @@ export type VersionOneConfig = {
   gaTrackingId?: string;
   highlight?: Record<string, unknown>;
   markdownPlugins?: Array<() => void>;
-  scripts?: Array<{src: string; [key: string]: any} | string>;
-  stylesheets?: Array<{href: string; [key: string]: any} | string>;
+  scripts?: Array<{src: string; [key: string]: unknown} | string>;
+  stylesheets?: Array<{href: string; [key: string]: unknown} | string>;
   facebookAppId?: string;
   facebookComments?: true;
   facebookPixelId?: string;
diff --git a/packages/docusaurus-module-type-aliases/src/index.d.ts b/packages/docusaurus-module-type-aliases/src/index.d.ts
index 0b36d70594..112b45660f 100644
--- a/packages/docusaurus-module-type-aliases/src/index.d.ts
+++ b/packages/docusaurus-module-type-aliases/src/index.d.ts
@@ -43,7 +43,7 @@ declare module '@generated/routesChunkNames' {
 }
 
 declare module '@generated/globalData' {
-  const globalData: any;
+  const globalData: Record<string, unknown>;
   export default globalData;
 }
 
diff --git a/packages/docusaurus-plugin-content-docs/src/docs.ts b/packages/docusaurus-plugin-content-docs/src/docs.ts
index 2aac56b618..4902c08f9b 100644
--- a/packages/docusaurus-plugin-content-docs/src/docs.ts
+++ b/packages/docusaurus-plugin-content-docs/src/docs.ts
@@ -120,7 +120,10 @@ export function processDocMetadata({
   const docsFileDirName = path.dirname(source);
 
   const {frontMatter = {}, excerpt} = parseMarkdownString(content);
-  const {sidebar_label, custom_edit_url} = frontMatter;
+  const {
+    sidebar_label: sidebarLabel,
+    custom_edit_url: customEditURL,
+  } = frontMatter;
 
   const baseID: string =
     frontMatter.id || path.basename(source, path.extname(source));
@@ -206,7 +209,7 @@ export function processDocMetadata({
     source: aliasedSitePath(filePath, siteDir),
     slug: docSlug,
     permalink,
-    editUrl: custom_edit_url !== undefined ? custom_edit_url : getDocEditUrl(),
+    editUrl: customEditURL !== undefined ? customEditURL : getDocEditUrl(),
     version: versionMetadata.versionName,
     lastUpdatedBy: lastUpdate.lastUpdatedBy,
     lastUpdatedAt: lastUpdate.lastUpdatedAt,
@@ -215,6 +218,6 @@ export function processDocMetadata({
           lastUpdate.lastUpdatedAt * 1000,
         )
       : undefined,
-    sidebar_label,
+    sidebar_label: sidebarLabel,
   };
 }
diff --git a/packages/docusaurus-plugin-content-docs/src/plugin-content-docs.d.ts b/packages/docusaurus-plugin-content-docs/src/plugin-content-docs.d.ts
index 5ca68ee3a3..9d398b5dca 100644
--- a/packages/docusaurus-plugin-content-docs/src/plugin-content-docs.d.ts
+++ b/packages/docusaurus-plugin-content-docs/src/plugin-content-docs.d.ts
@@ -22,7 +22,7 @@ declare module '@docusaurus/plugin-content-docs-types' {
   };
 
   type PropsSidebarItemBase = {
-    customProps?: object;
+    customProps?: Record<string, unknown>;
   };
 
   export type PropSidebarItemLink = PropsSidebarItemBase & {
diff --git a/packages/docusaurus-plugin-content-docs/src/props.ts b/packages/docusaurus-plugin-content-docs/src/props.ts
index b0c512c191..994fe17013 100644
--- a/packages/docusaurus-plugin-content-docs/src/props.ts
+++ b/packages/docusaurus-plugin-content-docs/src/props.ts
@@ -33,11 +33,11 @@ Available document ids=
       );
     }
 
-    const {title, permalink, sidebar_label} = docMetadata;
+    const {title, permalink, sidebar_label: sidebarLabel} = docMetadata;
 
     return {
       type: 'link',
-      label: sidebar_label || title,
+      label: sidebarLabel || title,
       href: permalink,
       customProps: item.customProps,
     };
diff --git a/packages/docusaurus-plugin-content-docs/src/sidebars.ts b/packages/docusaurus-plugin-content-docs/src/sidebars.ts
index 53b0e35e4b..058791d58b 100644
--- a/packages/docusaurus-plugin-content-docs/src/sidebars.ts
+++ b/packages/docusaurus-plugin-content-docs/src/sidebars.ts
@@ -76,7 +76,7 @@ function normalizeCategoryShorthand(
  * Check that item contains only allowed keys.
  */
 function assertItem<K extends string>(
-  item: any,
+  item: Record<string, unknown>,
   keys: K[],
 ): asserts item is Record<K, any> {
   const unknownKeys = Object.keys(item).filter(
@@ -94,7 +94,7 @@ function assertItem<K extends string>(
 }
 
 function assertIsCategory(
-  item: unknown,
+  item: Record<string, unknown>,
 ): asserts item is SidebarItemCategoryJSON {
   assertItem(item, ['items', 'label', 'collapsed', 'customProps']);
   if (typeof item.label !== 'string') {
@@ -115,7 +115,9 @@ function assertIsCategory(
   }
 }
 
-function assertIsDoc(item: unknown): asserts item is SidebarItemDoc {
+function assertIsDoc(
+  item: Record<string, unknown>,
+): asserts item is SidebarItemDoc {
   assertItem(item, ['id', 'customProps']);
   if (typeof item.id !== 'string') {
     throw new Error(
@@ -124,7 +126,9 @@ function assertIsDoc(item: unknown): asserts item is SidebarItemDoc {
   }
 }
 
-function assertIsLink(item: unknown): asserts item is SidebarItemLink {
+function assertIsLink(
+  item: Record<string, unknown>,
+): asserts item is SidebarItemLink {
   assertItem(item, ['href', 'label', 'customProps']);
   if (typeof item.href !== 'string') {
     throw new Error(
diff --git a/packages/docusaurus-plugin-content-docs/src/theme/hooks/useDocs.ts b/packages/docusaurus-plugin-content-docs/src/theme/hooks/useDocs.ts
index fbf0d21155..9c9e2b7884 100644
--- a/packages/docusaurus-plugin-content-docs/src/theme/hooks/useDocs.ts
+++ b/packages/docusaurus-plugin-content-docs/src/theme/hooks/useDocs.ts
@@ -27,7 +27,7 @@ import {
 export const useAllDocsData = (): Record<string, GlobalPluginData> =>
   useAllPluginInstancesData('docusaurus-plugin-content-docs');
 
-export const useDocsData = (pluginId: string | undefined) =>
+export const useDocsData = (pluginId: string | undefined): GlobalPluginData =>
   usePluginData('docusaurus-plugin-content-docs', pluginId) as GlobalPluginData;
 
 export const useActivePlugin = (
diff --git a/packages/docusaurus-plugin-content-docs/src/types.ts b/packages/docusaurus-plugin-content-docs/src/types.ts
index 25261ad0b9..730f7da883 100644
--- a/packages/docusaurus-plugin-content-docs/src/types.ts
+++ b/packages/docusaurus-plugin-content-docs/src/types.ts
@@ -94,7 +94,7 @@ export type PluginOptions = MetadataOptions &
   };
 
 export type SidebarItemBase = {
-  customProps?: object;
+  customProps?: Record<string, unknown>;
 };
 
 export type SidebarItemDoc = SidebarItemBase & {
@@ -147,6 +147,7 @@ export type DocMetadataBase = LastUpdateData & {
   source: string;
   slug: string;
   permalink: string;
+  // eslint-disable-next-line camelcase
   sidebar_label?: string;
   editUrl?: string | null;
 };
diff --git a/packages/docusaurus-plugin-content-docs/src/versions.ts b/packages/docusaurus-plugin-content-docs/src/versions.ts
index 2131c3c628..732d9eecd7 100644
--- a/packages/docusaurus-plugin-content-docs/src/versions.ts
+++ b/packages/docusaurus-plugin-content-docs/src/versions.ts
@@ -427,7 +427,7 @@ function filterVersions(
 ) {
   if (options.onlyIncludeVersions) {
     return versionNamesUnfiltered.filter((name) =>
-      options.onlyIncludeVersions!.includes(name),
+      (options.onlyIncludeVersions || []).includes(name),
     );
   } else {
     return versionNamesUnfiltered;
diff --git a/packages/docusaurus-plugin-content-pages/src/__tests__/index.test.ts b/packages/docusaurus-plugin-content-pages/src/__tests__/index.test.ts
index cedd171041..717a82e38b 100644
--- a/packages/docusaurus-plugin-content-pages/src/__tests__/index.test.ts
+++ b/packages/docusaurus-plugin-content-pages/src/__tests__/index.test.ts
@@ -22,7 +22,7 @@ describe('docusaurus-plugin-content-pages', () => {
         path: pluginPath,
       }),
     );
-    const pagesMetadatas = (await plugin.loadContent?.())!;
+    const pagesMetadatas = await plugin.loadContent?.();
 
     expect(pagesMetadatas).toEqual([
       {
@@ -89,7 +89,7 @@ describe('docusaurus-plugin-content-pages', () => {
         path: pluginPath,
       }),
     );
-    const pagesMetadatas = (await plugin.loadContent?.())!;
+    const pagesMetadatas = await plugin.loadContent?.();
 
     const frTranslationsPath = path.posix.join(
       '@site',
diff --git a/packages/docusaurus-plugin-content-pages/src/plugin-content-pages.d.ts b/packages/docusaurus-plugin-content-pages/src/plugin-content-pages.d.ts
index 4bc3a58094..0b3ba8e6ff 100644
--- a/packages/docusaurus-plugin-content-pages/src/plugin-content-pages.d.ts
+++ b/packages/docusaurus-plugin-content-pages/src/plugin-content-pages.d.ts
@@ -14,6 +14,7 @@ declare module '@theme/MDXPage' {
         readonly title: string;
         readonly description: string;
         readonly wrapperClassName?: string;
+        // eslint-disable-next-line camelcase
         readonly hide_table_of_contents?: string;
       };
       readonly metadata: {readonly permalink: string};
diff --git a/packages/docusaurus-plugin-debug/src/theme/DebugJsonView/index.js b/packages/docusaurus-plugin-debug/src/theme/DebugJsonView/index.js
index f8ec854d97..d0a02ffeae 100644
--- a/packages/docusaurus-plugin-debug/src/theme/DebugJsonView/index.js
+++ b/packages/docusaurus-plugin-debug/src/theme/DebugJsonView/index.js
@@ -18,6 +18,7 @@ const BrowserOnlyReactJson = (props) => {
   return (
     <BrowserOnly>
       {() => {
+        // eslint-disable-next-line global-require
         const ReactJson = require('react-json-view').default;
         return <ReactJson {...props} />;
       }}
diff --git a/packages/docusaurus-theme-bootstrap/src/theme/CodeBlock/index.tsx b/packages/docusaurus-theme-bootstrap/src/theme/CodeBlock/index.tsx
index 0873494ffb..4775f1706a 100644
--- a/packages/docusaurus-theme-bootstrap/src/theme/CodeBlock/index.tsx
+++ b/packages/docusaurus-theme-bootstrap/src/theme/CodeBlock/index.tsx
@@ -6,10 +6,11 @@
  */
 
 import React from 'react';
-import Highlight, {defaultProps} from 'prism-react-renderer';
+import Highlight, {defaultProps, Language} from 'prism-react-renderer';
 import theme from 'prism-react-renderer/themes/nightOwl';
+import type {Props} from '@theme/CodeBlock';
 
-export default ({children, className}): JSX.Element => {
+export default ({children, className}: Props): JSX.Element => {
   const language = className && className.replace(/language-/, '');
 
   return (
@@ -17,7 +18,7 @@ export default ({children, className}): JSX.Element => {
       {...defaultProps}
       theme={theme}
       code={children}
-      language={language}>
+      language={language as Language}>
       {({style, tokens, getLineProps, getTokenProps}) => (
         <pre className={className} style={{...style, padding: '20px'}}>
           {tokens.map((line, i) => (
diff --git a/packages/docusaurus-theme-bootstrap/src/theme/Footer/index.tsx b/packages/docusaurus-theme-bootstrap/src/theme/Footer/index.tsx
index 90a210a25b..196df050aa 100644
--- a/packages/docusaurus-theme-bootstrap/src/theme/Footer/index.tsx
+++ b/packages/docusaurus-theme-bootstrap/src/theme/Footer/index.tsx
@@ -30,7 +30,7 @@ function FooterLink({to, href, label, ...props}) {
   );
 }
 
-function Footer() {
+function Footer(): JSX.Element {
   const context = useDocusaurusContext();
   const {siteConfig = {}} = context;
   const {themeConfig = {}} = siteConfig;
diff --git a/packages/docusaurus-theme-bootstrap/src/theme/MDXComponents/index.tsx b/packages/docusaurus-theme-bootstrap/src/theme/MDXComponents/index.tsx
index 08a45cf4eb..b5d3cd1b77 100644
--- a/packages/docusaurus-theme-bootstrap/src/theme/MDXComponents/index.tsx
+++ b/packages/docusaurus-theme-bootstrap/src/theme/MDXComponents/index.tsx
@@ -6,7 +6,7 @@
  */
 
 import React, {ReactNode} from 'react';
-import CodeBlock from '@theme/CodeBlock';
+import CodeBlock, {Props} from '@theme/CodeBlock';
 import {Table} from 'reactstrap';
 
 const Heading = (tag: string): ReactNode => {
@@ -22,7 +22,7 @@ export default {
   h4: Heading('h4'),
   h5: Heading('h5'),
   h6: Heading('h6'),
-  code: (props) => {
+  code: (props: Props): JSX.Element => {
     const {children} = props;
     if (typeof children === 'string') {
       return <CodeBlock {...props} />;
@@ -30,8 +30,10 @@ export default {
     return children;
   },
   table: Table,
-  blockquote: (props) => (
+  blockquote: (props: {children: ReactNode}): JSX.Element => (
     <blockquote className="blockquote-footer">{props.children}</blockquote>
   ),
-  p: (props) => <div className="font-weight-light">{props.children}</div>,
+  p: (props: {children: ReactNode}): JSX.Element => (
+    <div className="font-weight-light">{props.children}</div>
+  ),
 };
diff --git a/packages/docusaurus-theme-bootstrap/src/theme/Navbar/index.tsx b/packages/docusaurus-theme-bootstrap/src/theme/Navbar/index.tsx
index e36ce9546b..6e27f1a3d5 100644
--- a/packages/docusaurus-theme-bootstrap/src/theme/Navbar/index.tsx
+++ b/packages/docusaurus-theme-bootstrap/src/theme/Navbar/index.tsx
@@ -62,7 +62,7 @@ function NavItem({
   );
 }
 
-function Navbar() {
+function Navbar(): JSX.Element {
   const {
     siteConfig: {
       themeConfig: {navbar: {title = '', items: links = []} = {}},
diff --git a/packages/docusaurus-theme-bootstrap/src/theme/TOCInline/index.tsx b/packages/docusaurus-theme-bootstrap/src/theme/TOCInline/index.tsx
index e231482602..84cb984ac3 100644
--- a/packages/docusaurus-theme-bootstrap/src/theme/TOCInline/index.tsx
+++ b/packages/docusaurus-theme-bootstrap/src/theme/TOCInline/index.tsx
@@ -7,7 +7,7 @@
 
 import React from 'react';
 
-function TOCInline(_props: any): JSX.Element {
+function TOCInline(_props: Record<string, unknown>): JSX.Element {
   return <div>TODO bootstrap toc</div>;
 }
 
diff --git a/packages/docusaurus-theme-classic/src/__tests__/validateThemeConfig.test.js b/packages/docusaurus-theme-classic/src/__tests__/validateThemeConfig.test.js
index a7d1a78397..d21adbfc72 100644
--- a/packages/docusaurus-theme-classic/src/__tests__/validateThemeConfig.test.js
+++ b/packages/docusaurus-theme-classic/src/__tests__/validateThemeConfig.test.js
@@ -10,6 +10,8 @@ import {merge} from 'lodash';
 const {ThemeConfigSchema, DEFAULT_CONFIG} = require('../validateThemeConfig');
 
 const {normalizeThemeConfig} = require('@docusaurus/utils-validation');
+const theme = require('prism-react-renderer/themes/github');
+const darkTheme = require('prism-react-renderer/themes/dracula');
 
 function testValidateThemeConfig(partialThemeConfig) {
   return normalizeThemeConfig(ThemeConfigSchema, {
@@ -31,8 +33,8 @@ describe('themeConfig', () => {
   test('should accept valid theme config', () => {
     const userConfig = {
       prism: {
-        theme: require('prism-react-renderer/themes/github'),
-        darkTheme: require('prism-react-renderer/themes/dracula'),
+        theme,
+        darkTheme,
         defaultLanguage: 'javascript',
         additionalLanguages: ['kotlin', 'java'],
       },
diff --git a/packages/docusaurus-theme-classic/src/theme/Footer/index.tsx b/packages/docusaurus-theme-classic/src/theme/Footer/index.tsx
index 0c1ebe6749..bd96e8a5e0 100644
--- a/packages/docusaurus-theme-classic/src/theme/Footer/index.tsx
+++ b/packages/docusaurus-theme-classic/src/theme/Footer/index.tsx
@@ -9,12 +9,18 @@ import React from 'react';
 import clsx from 'clsx';
 
 import Link from '@docusaurus/Link';
-import {useThemeConfig} from '@docusaurus/theme-common';
+import {FooterLinkItem, useThemeConfig} from '@docusaurus/theme-common';
 import useBaseUrl from '@docusaurus/useBaseUrl';
 import styles from './styles.module.css';
 import ThemedImage, {Props as ThemedImageProps} from '@theme/ThemedImage';
 
-function FooterLink({to, href, label, prependBaseUrlToHref, ...props}: any) {
+function FooterLink({
+  to,
+  href,
+  label,
+  prependBaseUrlToHref,
+  ...props
+}: FooterLinkItem) {
   const toUrl = useBaseUrl(to);
   const normalizedHref = useBaseUrl(href, {forcePrependBaseUrl: true});
 
diff --git a/packages/docusaurus-theme-classic/src/theme/MDXComponents/index.tsx b/packages/docusaurus-theme-classic/src/theme/MDXComponents/index.tsx
index e121958d4d..8d51e334a5 100644
--- a/packages/docusaurus-theme-classic/src/theme/MDXComponents/index.tsx
+++ b/packages/docusaurus-theme-classic/src/theme/MDXComponents/index.tsx
@@ -23,7 +23,7 @@ const MDXComponents: MDXComponentsObject = {
     return children;
   },
   a: (props) => <Link {...props} />,
-  pre: (props: any) => {
+  pre: (props) => {
     const {children} = props;
     return (
       <CodeBlock
diff --git a/packages/docusaurus-theme-classic/src/theme/NavbarItem/index.tsx b/packages/docusaurus-theme-classic/src/theme/NavbarItem/index.tsx
index 70451c855c..f1ed6f5a44 100644
--- a/packages/docusaurus-theme-classic/src/theme/NavbarItem/index.tsx
+++ b/packages/docusaurus-theme-classic/src/theme/NavbarItem/index.tsx
@@ -19,13 +19,13 @@ const NavbarItemComponents = {
   // Need to lazy load these items as we don't know for sure the docs plugin is loaded
   // See https://github.com/facebook/docusaurus/issues/3360
   docsVersion: () =>
-    // eslint-disable-next-line @typescript-eslint/no-var-requires
+    // eslint-disable-next-line @typescript-eslint/no-var-requires, global-require
     require('@theme/NavbarItem/DocsVersionNavbarItem').default,
   docsVersionDropdown: () =>
-    // eslint-disable-next-line @typescript-eslint/no-var-requires
+    // eslint-disable-next-line @typescript-eslint/no-var-requires, global-require
     require('@theme/NavbarItem/DocsVersionDropdownNavbarItem').default,
   doc: () =>
-    // eslint-disable-next-line @typescript-eslint/no-var-requires
+    // eslint-disable-next-line @typescript-eslint/no-var-requires, global-require
     require('@theme/NavbarItem/DocNavbarItem').default,
 } as const;
 
diff --git a/packages/docusaurus-theme-classic/src/theme/hooks/useDocs.ts b/packages/docusaurus-theme-classic/src/theme/hooks/useDocs.ts
index e0b1552d50..985ab8a040 100644
--- a/packages/docusaurus-theme-classic/src/theme/hooks/useDocs.ts
+++ b/packages/docusaurus-theme-classic/src/theme/hooks/useDocs.ts
@@ -12,6 +12,7 @@
 // see https://github.com/webpack/webpack/issues/7713#issuecomment-467888437
 // note: warning can be filtered: https://github.com/facebook/docusaurus/pull/3382#issuecomment-684966924
 try {
+  // eslint-disable-next-line global-require
   module.exports = require('@theme-init/hooks/useDocs');
 } catch (e) {
   // In case the docs plugin is not available, might be useful to stub some methods here
diff --git a/packages/docusaurus-theme-common/package.json b/packages/docusaurus-theme-common/package.json
index 8ac4ffd07e..75de705826 100644
--- a/packages/docusaurus-theme-common/package.json
+++ b/packages/docusaurus-theme-common/package.json
@@ -29,6 +29,7 @@
     "@docusaurus/module-type-aliases": "2.0.0-alpha.72"
   },
   "peerDependencies": {
+    "prism-react-renderer": "^1.1.1",
     "react": "^16.8.4 || ^17.0.0",
     "react-dom": "^16.8.4 || ^17.0.0"
   },
diff --git a/packages/docusaurus-theme-common/src/utils/docsPreferredVersion/useDocsPreferredVersion.ts b/packages/docusaurus-theme-common/src/utils/docsPreferredVersion/useDocsPreferredVersion.ts
index c9df4cbc8c..d4d0ef4cd2 100644
--- a/packages/docusaurus-theme-common/src/utils/docsPreferredVersion/useDocsPreferredVersion.ts
+++ b/packages/docusaurus-theme-common/src/utils/docsPreferredVersion/useDocsPreferredVersion.ts
@@ -37,7 +37,7 @@ export function useDocsPreferredVersion(
   return {preferredVersion, savePreferredVersionName} as const;
 }
 
-export function useDocsPreferredVersionByPluginId() {
+export function useDocsPreferredVersionByPluginId(): Record<string, any> {
   const allDocsData = useAllDocsData();
   const [state] = useDocsPreferredVersionContext();
 
diff --git a/packages/docusaurus-theme-common/src/utils/useThemeConfig.ts b/packages/docusaurus-theme-common/src/utils/useThemeConfig.ts
index 84e2895b44..5289da2cf4 100644
--- a/packages/docusaurus-theme-common/src/utils/useThemeConfig.ts
+++ b/packages/docusaurus-theme-common/src/utils/useThemeConfig.ts
@@ -5,6 +5,8 @@
  * LICENSE file in the root directory of this source tree.
  */
 import useDocusaurusContext from '@docusaurus/useDocusaurusContext';
+import {PrismTheme} from 'prism-react-renderer';
+import {CSSProperties} from 'react';
 
 export type DocsVersionPersistence = 'localStorage' | 'none';
 
@@ -32,11 +34,39 @@ export type Navbar = {
   logo?: NavbarLogo;
 };
 
+export type ColorModeConfig = {
+  defaultMode: 'light' | 'dark';
+  disableSwitch: boolean;
+  respectPrefersColorScheme: boolean;
+  switchConfig: {
+    darkIcon: string;
+    darkIconStyle: CSSProperties;
+    lightIcon: string;
+    lightIconStyle: CSSProperties;
+  };
+};
+
+export type AnnouncementBarConfig = {
+  id: string;
+  content: string;
+  backgroundColor: string;
+  textColor: string;
+  isCloseable: boolean;
+};
+
+export type PrismConfig = {
+  theme?: PrismTheme;
+  darkTheme?: PrismTheme;
+  defaultLanguage?: string;
+  additionalLanguages?: string[];
+};
+
 export type FooterLinkItem = {
   label?: string;
   to?: string;
   href?: string;
   html?: string;
+  prependBaseUrlToHref?: string;
 };
 export type FooterLinks = {
   title?: string;
@@ -65,11 +95,11 @@ export type ThemeConfig = {
 
   // TODO temporary types
   navbar: Navbar;
-  colorMode: any;
-  announcementBar: any;
-  prism: any;
-  footer: Footer | undefined;
-  hideableSidebar: any;
+  colorMode: ColorModeConfig;
+  announcementBar?: AnnouncementBarConfig;
+  prism: PrismConfig;
+  footer?: Footer;
+  hideableSidebar: boolean;
 };
 
 export function useThemeConfig(): ThemeConfig {
diff --git a/packages/docusaurus-utils/src/index.ts b/packages/docusaurus-utils/src/index.ts
index 8a78a87a5b..1f60936877 100644
--- a/packages/docusaurus-utils/src/index.ts
+++ b/packages/docusaurus-utils/src/index.ts
@@ -26,7 +26,7 @@ const fileHash = new Map();
 export async function generate(
   generatedFilesDir: string,
   file: string,
-  content: any,
+  content: string,
   skipCache: boolean = process.env.NODE_ENV === 'production',
 ): Promise<void> {
   const filepath = path.join(generatedFilesDir, file);
@@ -57,11 +57,13 @@ export async function generate(
   }
 }
 
-export function objectWithKeySorted(obj: {[index: string]: any}) {
+export function objectWithKeySorted<T>(
+  obj: Record<string, T>,
+): Record<string, T> {
   // https://github.com/lodash/lodash/issues/1459#issuecomment-460941233
   return Object.keys(obj)
     .sort()
-    .reduce((acc: any, key: string) => {
+    .reduce((acc: Record<string, T>, key: string) => {
       acc[key] = obj[key];
       return acc;
     }, {});
diff --git a/packages/docusaurus/bin/docusaurus.js b/packages/docusaurus/bin/docusaurus.js
index 57fbf4429e..cb153e8f1b 100755
--- a/packages/docusaurus/bin/docusaurus.js
+++ b/packages/docusaurus/bin/docusaurus.js
@@ -45,7 +45,7 @@ if (notifier.lastUpdateCheck === Date.now()) {
 }
 
 if (notifier.update && notifier.update.current !== notifier.update.latest) {
-  // eslint-disable-next-line import/no-dynamic-require
+  // eslint-disable-next-line import/no-dynamic-require, global-require
   const sitePkg = require(path.resolve(process.cwd(), 'package.json'));
   const siteDocusaurusPackagesForUpdate = Object.keys(sitePkg.dependencies)
     .filter((p) => p.startsWith('@docusaurus'))
diff --git a/packages/docusaurus/src/choosePort.ts b/packages/docusaurus/src/choosePort.ts
index b1eee4e9b6..de6879cfec 100644
--- a/packages/docusaurus/src/choosePort.ts
+++ b/packages/docusaurus/src/choosePort.ts
@@ -111,7 +111,7 @@ export default async function choosePort(
             )}\n\nWould you like to run the app on another port instead?`,
             initial: true,
           };
-          prompts(question).then((answer: any) => {
+          prompts(question).then((answer) => {
             if (answer.shouldChangePort === true) {
               resolve(port);
             } else {
diff --git a/packages/docusaurus/src/client/docusaurus.ts b/packages/docusaurus/src/client/docusaurus.ts
index fd6c0365bb..4de063af3c 100644
--- a/packages/docusaurus/src/client/docusaurus.ts
+++ b/packages/docusaurus/src/client/docusaurus.ts
@@ -18,7 +18,7 @@ declare global {
   // eslint-disable-next-line camelcase, @typescript-eslint/no-explicit-any
   const __webpack_require__: {gca: (name: string) => string};
   interface Navigator {
-    connection: any;
+    connection: {effectiveType: string; saveData: boolean};
   }
 }
 
diff --git a/packages/docusaurus/src/client/exports/Interpolate.tsx b/packages/docusaurus/src/client/exports/Interpolate.tsx
index 09ce362bd1..bbb252c240 100644
--- a/packages/docusaurus/src/client/exports/Interpolate.tsx
+++ b/packages/docusaurus/src/client/exports/Interpolate.tsx
@@ -101,6 +101,6 @@ export type InterpolateProps<Str extends string> = {
 export default function Interpolate<Str extends string>({
   children,
   values,
-}: InterpolateProps<Str>) {
+}: InterpolateProps<Str>): ReactNode {
   return interpolate(children, values);
 }
diff --git a/packages/docusaurus/src/client/exports/Link.tsx b/packages/docusaurus/src/client/exports/Link.tsx
index c3ce4fae8b..9c1504507a 100644
--- a/packages/docusaurus/src/client/exports/Link.tsx
+++ b/packages/docusaurus/src/client/exports/Link.tsx
@@ -15,7 +15,10 @@ import {useBaseUrlUtils} from './useBaseUrl';
 
 declare global {
   interface Window {
-    docusaurus: any;
+    docusaurus: {
+      prefetch: (routePath: string) => boolean;
+      preload: (routePath: string) => boolean;
+    };
   }
 }
 
@@ -113,13 +116,15 @@ function Link({
     if (IOSupported && ref && isInternal) {
       // If IO supported and element reference found, setup Observer functionality.
       handleIntersection(ref, () => {
-        window.docusaurus.prefetch(targetLink);
+        if (targetLink != null) {
+          window.docusaurus.prefetch(targetLink);
+        }
       });
     }
   };
 
   const onMouseEnter = () => {
-    if (!preloaded.current) {
+    if (!preloaded.current && targetLink != null) {
       window.docusaurus.preload(targetLink);
       preloaded.current = true;
     }
@@ -128,7 +133,9 @@ function Link({
   useEffect(() => {
     // If IO is not supported. We prefetch by default (only once).
     if (!IOSupported && isInternal) {
-      window.docusaurus.prefetch(targetLink);
+      if (targetLink != null) {
+        window.docusaurus.prefetch(targetLink);
+      }
     }
 
     // When unmounting, stop intersection observer from watching.
diff --git a/packages/docusaurus/src/client/exports/useGlobalData.ts b/packages/docusaurus/src/client/exports/useGlobalData.ts
index b98fc32c35..8ed4a1a284 100644
--- a/packages/docusaurus/src/client/exports/useGlobalData.ts
+++ b/packages/docusaurus/src/client/exports/useGlobalData.ts
@@ -13,7 +13,7 @@ import useDocusaurusContext from './useDocusaurusContext';
 // import {DEFAULT_PLUGIN_ID} from '../../constants';
 const DEFAULT_PLUGIN_ID = 'default';
 
-export default function useGlobalData() {
+export default function useGlobalData(): Record<string, unknown> {
   const {globalData} = useDocusaurusContext();
   if (!globalData) {
     throw new Error('Docusaurus global data not found');
@@ -31,7 +31,7 @@ export function useAllPluginInstancesData<T = unknown>(
       `Docusaurus plugin global data not found for pluginName=${pluginName}`,
     );
   }
-  return pluginGlobalData;
+  return pluginGlobalData as Record<string, T>;
 }
 
 export function usePluginData<T = unknown>(
diff --git a/packages/docusaurus/src/commands/build.ts b/packages/docusaurus/src/commands/build.ts
index 1e28ab4d99..8dbde60280 100644
--- a/packages/docusaurus/src/commands/build.ts
+++ b/packages/docusaurus/src/commands/build.ts
@@ -91,7 +91,7 @@ export default async function build(
         i18n.locales.indexOf(locale) === i18n.locales.length - 1;
       return tryToBuildLocale({locale, isLastLocale});
     });
-    return results[0]!;
+    return results[0];
   }
 }
 
diff --git a/packages/docusaurus/src/server/plugins/index.ts b/packages/docusaurus/src/server/plugins/index.ts
index 16ee8867c3..3da9916c5f 100644
--- a/packages/docusaurus/src/server/plugins/index.ts
+++ b/packages/docusaurus/src/server/plugins/index.ts
@@ -69,7 +69,7 @@ export async function loadPlugins({
 }): Promise<{
   plugins: InitPlugin[];
   pluginsRouteConfigs: RouteConfig[];
-  globalData: any;
+  globalData: unknown;
   themeConfigTranslated: ThemeConfig;
 }> {
   // 1. Plugin Lifecycle - Initialization/Constructor.
diff --git a/packages/docusaurus/src/server/presets/index.ts b/packages/docusaurus/src/server/presets/index.ts
index f970f6880d..6e7b6e44ea 100644
--- a/packages/docusaurus/src/server/presets/index.ts
+++ b/packages/docusaurus/src/server/presets/index.ts
@@ -42,9 +42,15 @@ export default function loadPresets(
       throw new Error('Invalid presets format detected in config.');
     }
 
-    const presetModule: any = importFresh(
-      pluginRequire.resolve(presetModuleImport),
-    );
+    type PresetInitializeFunction = (
+      context: LoadContext,
+      presetOptions: Record<string, unknown>,
+    ) => Preset;
+    const presetModule = importFresh<
+      PresetInitializeFunction & {
+        default?: PresetInitializeFunction;
+      }
+    >(pluginRequire.resolve(presetModuleImport));
     const preset: Preset = (presetModule.default || presetModule)(
       context,
       presetOptions,
diff --git a/packages/docusaurus/src/server/translations/__tests__/translations.test.ts b/packages/docusaurus/src/server/translations/__tests__/translations.test.ts
index e18efe3e68..2b816a4acf 100644
--- a/packages/docusaurus/src/server/translations/__tests__/translations.test.ts
+++ b/packages/docusaurus/src/server/translations/__tests__/translations.test.ts
@@ -552,7 +552,7 @@ describe('getPluginsDefaultCodeTranslationMessages', () => {
 });
 
 describe('applyDefaultCodeTranslations', () => {
-  const consoleSpy = jest.spyOn(console, 'warn').mockImplementation() as any;
+  const consoleSpy = jest.spyOn(console, 'warn').mockImplementation();
   beforeEach(() => {
     consoleSpy.mockClear();
   });
diff --git a/packages/docusaurus/src/webpack/utils.ts b/packages/docusaurus/src/webpack/utils.ts
index e19c4a9481..7a959f0c8a 100644
--- a/packages/docusaurus/src/webpack/utils.ts
+++ b/packages/docusaurus/src/webpack/utils.ts
@@ -11,6 +11,7 @@ import merge from 'webpack-merge';
 import webpack, {
   Configuration,
   Loader,
+  NewLoader,
   Plugin,
   RuleSetRule,
   Stats,
@@ -23,7 +24,11 @@ import path from 'path';
 import crypto from 'crypto';
 import chalk from 'chalk';
 import {TransformOptions} from '@babel/core';
-import {ConfigureWebpackFn, ConfigurePostCssFn} from '@docusaurus/types';
+import {
+  ConfigureWebpackFn,
+  ConfigurePostCssFn,
+  PostCssOptions,
+} from '@docusaurus/types';
 import CssNanoPreset from '@docusaurus/cssnano-preset';
 import {version as cacheLoaderVersion} from 'cache-loader/package.json';
 import {
@@ -177,11 +182,13 @@ export function applyConfigurePostCss(
   configurePostCss: NonNullable<ConfigurePostCssFn>,
   config: Configuration,
 ): Configuration {
-  type LocalPostCSSLoader = Loader & {options: {postcssOptions: any}};
+  type LocalPostCSSLoader = Loader & {
+    options: {postcssOptions: PostCssOptions};
+  };
 
   // TODO not ideal heuristic but good enough for our usecase?
   function isPostCssLoader(loader: Loader): loader is LocalPostCSSLoader {
-    return !!(loader as any)?.options?.postcssOptions;
+    return !!(loader as NewLoader)?.options?.postcssOptions;
   }
 
   // Does not handle all edge cases, but good enough for now
@@ -207,7 +214,7 @@ export function applyConfigurePostCss(
 // See https://webpack.js.org/configuration/stats/#statswarningsfilter
 // @slorber: note sure why we have to re-implement this logic
 // just know that legacy had this only partially implemented, so completed it
-type WarningFilter = string | RegExp | Function;
+type WarningFilter = string | RegExp | ((warning: string) => boolean);
 function filterWarnings(
   warningsFilter: WarningFilter[],
   warnings: string[],