From 29994ae4cdfea7ca2842a542e7e4579263b0651e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Dudak?= <michal@mui.com>
Date: Mon, 7 Oct 2024 11:05:10 +0200
Subject: [PATCH 1/4] v1.0.0-alpha.3 (#709)

---
 CHANGELOG.md                   | 78 ++++++++++++++++++++++++++++++++++
 package.json                   |  2 +-
 packages/mui-base/package.json |  2 +-
 3 files changed, 80 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index bb7912268f..3fd8ded130 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,83 @@
 # Versions
 
+## v1.0.0-alpha.3
+
+_Oct 7, 2024_
+
+A big thanks to the 7 contributors who made this release possible. Here are some highlights ✨:
+
+- ⭐ We added several new components: CheckboxGroup, RadioGroup, Form, Separator
+- ⭐ Menu has new parts: CheckboxItem, RadioItem, and Group
+
+### `@base_ui/react@1.0.0-alpha.3`
+
+- [AlertDialog] Move types to namespaces (#591) @michaldudak
+- [Checkbox] Modernize implementation (#594) @atomiks
+- [CheckboxGroup] Implement components and hooks (#458) @atomiks
+- [Collapsible] Add Collapsible components and hooks (#481) @mj12albert
+- [Dialog] Move types to namespaces (#697) @michaldudak
+- [Dialog][Collapsible] Fix style prop merging (#641) @michaldudak
+- [Form] Create new `Form` component (#589) @atomiks
+- [Menu] CheckboxItem component (#533) @michaldudak
+- [Menu] Do not select an item when space is pressed during typeahead (#542) @michaldudak
+- [Menu] Fix custom anchor positioning (#609) @michaldudak
+- [Menu] Group and Separator components (#535) @michaldudak
+- [Menu] Increase test timeout (#592) @michaldudak
+- [Menu] RadioItem component (#534) @michaldudak
+- [Menu] Remove the unused prop (#647) @michaldudak
+- [Menu] Remove wrong default value from docs (#549) @sai6855
+- [Menu][Popover][PreviewCard][Tooltip] Add default value as `clippingAncestors` to collisionBoundary prop (#580) @sai6855
+- [NumberField] Modernize implementation (#590) @atomiks
+- [Popover] Modernize implementation (#607) @atomiks
+- [PreviewCard] Modernize implementation (#626) @atomiks
+- [RadioGroup] Create new `RadioGroup` component (#487) @atomiks
+- [Slider] Fix Home / End regression (#526) @sai6855
+- [Tooltip] Modernize implementation (#606) @atomiks
+- [useButton] Modernize implementation (#643) @michaldudak
+- [useScrollLock] Avoid scrollbar layout shift issues (#604) @atomiks
+
+### Docs
+
+- [docs] Fix 301 redirections in docs @oliviertassinari
+- [docs] Make the readme specific to @base_ui/react (#633) @michaldudak
+- [docs] Copy vale-action.yml from main repo @oliviertassinari
+- [docs] Fix 301 to chromium (#636) @oliviertassinari
+- [docs] Avoid dead links in demos (#610) @oliviertassinari
+- [docs] Fix rel attribute on edit GitHub links (#614) @oliviertassinari
+- [docs] Fix pnpm docs:link-check script (#552) @oliviertassinari
+- [docs] Fix Stack Overflow issue canned response @oliviertassinari
+- [docs] Fix outdated link to support page @oliviertassinari
+- [docs] Clarify contribution guide references @oliviertassinari
+
+### Core
+
+- [code-infra] Remove custom playwright installation steps (#646) @Janpot
+- [core] Fix 301 link to Next.js and git diff @oliviertassinari
+- [core] Fix package.json repository rule @oliviertassinari
+- [core] MUI X repository moved to a new location @oliviertassinari
+- [core] React 19 compatibility (#605) @michaldudak
+- [core] Reference `ownerDocument` (#660) @atomiks
+- [core] Remove 'use client' from index files (#331) @michaldudak
+- [core] Remove /.yarn (#596) @oliviertassinari
+- [core] Remove Material UI dependency (#585) @michaldudak
+- [core] Remove the legacy components from the repo (#584) @michaldudak
+- [core] Rename positionStrategy to positionMethod (#704) @michaldudak
+- [docs-infra] Fix double // (#613) @oliviertassinari
+- [docs-infra] Strengthen CSP (#595) @oliviertassinari
+- [infra] Adds reusable workflow for closing message on issues (#598) @michelengelen
+- [infra] Adds reusable workflow for issue cleanup (#597) @michelengelen
+- [infra] Fix line break in Stack Overflow message @oliviertassinari
+- [test] Fix tests on Safari (#546) @michaldudak
+- [test] Fix the test_types_next CI job (#703) @michaldudak
+- [test] Improve visual screenshot canva (#708)
+- [test] Point Istanbul to correct URL (#657) @sai6855
+- [test] Run Browserstack tests on master only (#578) @michaldudak
+- [test] Use `waitFor` instead of fixed timeout in tests (#632) @michaldudak
+- [website] Improve utm_source strategy @oliviertassinari
+- [website] Modernize the Base UI website (#538) @michaldudak
+
+All contributors of this release in alphabetical order: @atomiks, @Janpot, @michaldudak, @michelengelen, @mj12albert, @oliviertassinari, @sai6855
+
 ## v1.0.0-alpha.2
 
 _Aug 19, 2024_
diff --git a/package.json b/package.json
index 7fdca89621..d25331dc22 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@base_ui/monorepo",
-  "version": "1.0.0-alpha.2",
+  "version": "1.0.0-alpha.3",
   "private": true,
   "scripts": {
     "preinstall": "npx only-allow pnpm",
diff --git a/packages/mui-base/package.json b/packages/mui-base/package.json
index e922305204..e936c416a3 100644
--- a/packages/mui-base/package.json
+++ b/packages/mui-base/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@base_ui/react",
-  "version": "1.0.0-alpha.2",
+  "version": "1.0.0-alpha.3",
   "private": false,
   "author": "MUI Team",
   "description": "Base UI is a library of headless ('unstyled') React components and low-level hooks. You gain complete control over your app's CSS and accessibility features.",

From 2d712572504248528ed0ea352624b92c2dac74eb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Dudak?= <michal@mui.com>
Date: Mon, 7 Oct 2024 11:22:48 +0200
Subject: [PATCH 2/4] [Switch] Modernize implementation (#640)

---
 docs/data/api/switch-root.json                |   1 -
 .../css-modules/index.js                      | 127 ++----------------
 .../css-modules/index.tsx                     | 127 ++----------------
 .../css-modules/styles.module.css             |  80 +++++++++++
 .../tailwind/index.tsx                        |   6 +-
 .../api-docs/switch-root/switch-root.json     |   1 -
 .../mui-base/src/Switch/Root/SwitchContext.ts |   5 -
 .../mui-base/src/Switch/Root/SwitchRoot.tsx   |  64 ++++-----
 .../src/Switch/Root/SwitchRoot.types.ts       |  87 ------------
 .../src/Switch/Root/SwitchRootContext.ts      |  15 +++
 .../mui-base/src/Switch/Root/useSwitchRoot.ts |  88 ++++++++++--
 .../src/Switch/Root/useSwitchStyleHooks.ts    |  14 --
 .../src/Switch/Thumb/SwitchThumb.test.tsx     |   8 +-
 .../mui-base/src/Switch/Thumb/SwitchThumb.tsx |  50 +++----
 .../src/Switch/Thumb/SwitchThumb.types.ts     |   4 -
 packages/mui-base/src/Switch/index.barrel.ts  |  11 --
 packages/mui-base/src/Switch/index.ts         |  11 --
 packages/mui-base/src/Switch/styleHooks.ts    |   6 +
 18 files changed, 257 insertions(+), 448 deletions(-)
 create mode 100644 docs/data/components/switch/UnstyledSwitchIntroduction/css-modules/styles.module.css
 delete mode 100644 packages/mui-base/src/Switch/Root/SwitchContext.ts
 delete mode 100644 packages/mui-base/src/Switch/Root/SwitchRoot.types.ts
 create mode 100644 packages/mui-base/src/Switch/Root/SwitchRootContext.ts
 delete mode 100644 packages/mui-base/src/Switch/Root/useSwitchStyleHooks.ts
 delete mode 100644 packages/mui-base/src/Switch/Thumb/SwitchThumb.types.ts
 create mode 100644 packages/mui-base/src/Switch/styleHooks.ts

diff --git a/docs/data/api/switch-root.json b/docs/data/api/switch-root.json
index b63432c278..ab1c15cd36 100644
--- a/docs/data/api/switch-root.json
+++ b/docs/data/api/switch-root.json
@@ -4,7 +4,6 @@
     "className": { "type": { "name": "union", "description": "func<br>&#124;&nbsp;string" } },
     "defaultChecked": { "type": { "name": "bool" } },
     "disabled": { "type": { "name": "bool" }, "default": "false" },
-    "id": { "type": { "name": "string" } },
     "inputRef": { "type": { "name": "custom", "description": "ref" } },
     "name": { "type": { "name": "string" } },
     "onCheckedChange": {
diff --git a/docs/data/components/switch/UnstyledSwitchIntroduction/css-modules/index.js b/docs/data/components/switch/UnstyledSwitchIntroduction/css-modules/index.js
index ca04551ec5..d48f24dbea 100644
--- a/docs/data/components/switch/UnstyledSwitchIntroduction/css-modules/index.js
+++ b/docs/data/components/switch/UnstyledSwitchIntroduction/css-modules/index.js
@@ -1,148 +1,39 @@
 'use client';
 import * as React from 'react';
 import * as Switch from '@base_ui/react/Switch';
-import { useTheme } from '@mui/system';
+import classes from './styles.module.css';
 
 export default function UnstyledSwitchIntroduction() {
   return (
     <div>
       <Switch.Root
-        className="CustomSwitchIntroduction"
+        className={classes.root}
         aria-label="Basic switch, on by default"
         defaultChecked
       >
-        <Switch.Thumb className="CustomSwitchIntroduction-thumb" />
+        <Switch.Thumb className={classes.thumb} />
       </Switch.Root>
       <Switch.Root
-        className="CustomSwitchIntroduction"
+        className={classes.root}
         aria-label="Basic switch, off by default"
       >
-        <Switch.Thumb className="CustomSwitchIntroduction-thumb" />
+        <Switch.Thumb className={classes.thumb} />
       </Switch.Root>
       <Switch.Root
-        className="CustomSwitchIntroduction"
+        className={classes.root}
         aria-label="Disabled switch, on by default"
         defaultChecked
         disabled
       >
-        <Switch.Thumb className="CustomSwitchIntroduction-thumb" />
+        <Switch.Thumb className={classes.thumb} />
       </Switch.Root>
       <Switch.Root
-        className="CustomSwitchIntroduction"
+        className={classes.root}
         aria-label="Disabled switch, off by default"
         disabled
       >
-        <Switch.Thumb className="CustomSwitchIntroduction-thumb" />
+        <Switch.Thumb className={classes.thumb} />
       </Switch.Root>
-      <Styles />
     </div>
   );
 }
-
-const cyan = {
-  50: '#E9F8FC',
-  100: '#BDEBF4',
-  200: '#99D8E5',
-  300: '#66BACC',
-  400: '#1F94AD',
-  500: '#0D5463',
-  600: '#094855',
-  700: '#063C47',
-  800: '#043039',
-  900: '#022127',
-};
-
-const grey = {
-  50: '#F3F6F9',
-  100: '#E5EAF2',
-  200: '#DAE2ED',
-  300: '#C7D0DD',
-  400: '#B0B8C4',
-  500: '#9DA8B7',
-  600: '#6B7A90',
-  700: '#434D5B',
-  800: '#303740',
-  900: '#1C2025',
-};
-
-function useIsDarkMode() {
-  const theme = useTheme();
-  return theme.palette.mode === 'dark';
-}
-
-function Styles() {
-  // Replace this with your app logic for determining dark modes
-  const isDarkMode = useIsDarkMode();
-
-  return (
-    <style>
-      {`
-      .CustomSwitchIntroduction {
-        width: 38px;
-        height: 24px;
-        margin: 10px;
-        padding: 0;
-        box-sizing: border-box;
-        background: ${isDarkMode ? grey[900] : grey[50]};
-        border: 1px solid ${isDarkMode ? grey[800] : grey[200]};
-        border-radius: 24px;
-        display: inline-block;
-        transition-property: all;
-        transition-timing-function: cubic-bezier(0.4, 0, 0.2, 1);
-        transition-duration: 120ms;
-        box-shadow: inset 0px 1px 1px ${
-          isDarkMode ? 'rgba(0, 0, 0, 0.5)' : 'rgba(0, 0, 0, 0.05)'
-        };
-      }
-
-      .CustomSwitchIntroduction[data-disabled] {
-        opacity: 0.4;
-        cursor: not-allowed;
-      }
-
-      .CustomSwitchIntroduction:hover:not([data-disabled]) {
-        background: ${isDarkMode ? grey[800] : grey[100]};
-        border-color: ${isDarkMode ? grey[600] : grey[300]};
-      }
-    
-      .CustomSwitchIntroduction:focus-visible {
-        box-shadow: 0 0 0 3px ${isDarkMode ? cyan[700] : cyan[200]};
-      }
-    
-      .CustomSwitchIntroduction[data-state="checked"] {
-        border: none;
-        background: ${cyan[500]};
-      }
-    
-      .CustomSwitchIntroduction[data-state="checked"]:not([data-disabled]):hover {
-        background: ${cyan[700]};
-      }
-
-
-      .CustomSwitchIntroduction-thumb {
-        box-sizing: border-box;
-        border: 1px solid ${isDarkMode ? grey[800] : grey[200]};
-        display: block;
-        width: 16px;
-        height: 16px;
-        left: 4px;
-        border-radius: 16px;
-        background-color: #FFF;
-        position: relative;
-        transition-property: all;
-        transition-timing-function: cubic-bezier(0.4, 0, 0.2, 1);
-        transition-duration: 120ms;
-        box-shadow: 0px 1px 2px ${
-          isDarkMode ? 'rgba(0, 0, 0, 0.25)' : 'rgba(0, 0, 0, 0.1)'
-        };
-      }
-
-      .CustomSwitchIntroduction-thumb[data-state="checked"] {
-        left: 18px;
-        background-color: #fff;
-        box-shadow: 0px 1px 2px rgba(0, 0, 0, 0.3);
-      }
-    `}
-    </style>
-  );
-}
diff --git a/docs/data/components/switch/UnstyledSwitchIntroduction/css-modules/index.tsx b/docs/data/components/switch/UnstyledSwitchIntroduction/css-modules/index.tsx
index ca04551ec5..d48f24dbea 100644
--- a/docs/data/components/switch/UnstyledSwitchIntroduction/css-modules/index.tsx
+++ b/docs/data/components/switch/UnstyledSwitchIntroduction/css-modules/index.tsx
@@ -1,148 +1,39 @@
 'use client';
 import * as React from 'react';
 import * as Switch from '@base_ui/react/Switch';
-import { useTheme } from '@mui/system';
+import classes from './styles.module.css';
 
 export default function UnstyledSwitchIntroduction() {
   return (
     <div>
       <Switch.Root
-        className="CustomSwitchIntroduction"
+        className={classes.root}
         aria-label="Basic switch, on by default"
         defaultChecked
       >
-        <Switch.Thumb className="CustomSwitchIntroduction-thumb" />
+        <Switch.Thumb className={classes.thumb} />
       </Switch.Root>
       <Switch.Root
-        className="CustomSwitchIntroduction"
+        className={classes.root}
         aria-label="Basic switch, off by default"
       >
-        <Switch.Thumb className="CustomSwitchIntroduction-thumb" />
+        <Switch.Thumb className={classes.thumb} />
       </Switch.Root>
       <Switch.Root
-        className="CustomSwitchIntroduction"
+        className={classes.root}
         aria-label="Disabled switch, on by default"
         defaultChecked
         disabled
       >
-        <Switch.Thumb className="CustomSwitchIntroduction-thumb" />
+        <Switch.Thumb className={classes.thumb} />
       </Switch.Root>
       <Switch.Root
-        className="CustomSwitchIntroduction"
+        className={classes.root}
         aria-label="Disabled switch, off by default"
         disabled
       >
-        <Switch.Thumb className="CustomSwitchIntroduction-thumb" />
+        <Switch.Thumb className={classes.thumb} />
       </Switch.Root>
-      <Styles />
     </div>
   );
 }
-
-const cyan = {
-  50: '#E9F8FC',
-  100: '#BDEBF4',
-  200: '#99D8E5',
-  300: '#66BACC',
-  400: '#1F94AD',
-  500: '#0D5463',
-  600: '#094855',
-  700: '#063C47',
-  800: '#043039',
-  900: '#022127',
-};
-
-const grey = {
-  50: '#F3F6F9',
-  100: '#E5EAF2',
-  200: '#DAE2ED',
-  300: '#C7D0DD',
-  400: '#B0B8C4',
-  500: '#9DA8B7',
-  600: '#6B7A90',
-  700: '#434D5B',
-  800: '#303740',
-  900: '#1C2025',
-};
-
-function useIsDarkMode() {
-  const theme = useTheme();
-  return theme.palette.mode === 'dark';
-}
-
-function Styles() {
-  // Replace this with your app logic for determining dark modes
-  const isDarkMode = useIsDarkMode();
-
-  return (
-    <style>
-      {`
-      .CustomSwitchIntroduction {
-        width: 38px;
-        height: 24px;
-        margin: 10px;
-        padding: 0;
-        box-sizing: border-box;
-        background: ${isDarkMode ? grey[900] : grey[50]};
-        border: 1px solid ${isDarkMode ? grey[800] : grey[200]};
-        border-radius: 24px;
-        display: inline-block;
-        transition-property: all;
-        transition-timing-function: cubic-bezier(0.4, 0, 0.2, 1);
-        transition-duration: 120ms;
-        box-shadow: inset 0px 1px 1px ${
-          isDarkMode ? 'rgba(0, 0, 0, 0.5)' : 'rgba(0, 0, 0, 0.05)'
-        };
-      }
-
-      .CustomSwitchIntroduction[data-disabled] {
-        opacity: 0.4;
-        cursor: not-allowed;
-      }
-
-      .CustomSwitchIntroduction:hover:not([data-disabled]) {
-        background: ${isDarkMode ? grey[800] : grey[100]};
-        border-color: ${isDarkMode ? grey[600] : grey[300]};
-      }
-    
-      .CustomSwitchIntroduction:focus-visible {
-        box-shadow: 0 0 0 3px ${isDarkMode ? cyan[700] : cyan[200]};
-      }
-    
-      .CustomSwitchIntroduction[data-state="checked"] {
-        border: none;
-        background: ${cyan[500]};
-      }
-    
-      .CustomSwitchIntroduction[data-state="checked"]:not([data-disabled]):hover {
-        background: ${cyan[700]};
-      }
-
-
-      .CustomSwitchIntroduction-thumb {
-        box-sizing: border-box;
-        border: 1px solid ${isDarkMode ? grey[800] : grey[200]};
-        display: block;
-        width: 16px;
-        height: 16px;
-        left: 4px;
-        border-radius: 16px;
-        background-color: #FFF;
-        position: relative;
-        transition-property: all;
-        transition-timing-function: cubic-bezier(0.4, 0, 0.2, 1);
-        transition-duration: 120ms;
-        box-shadow: 0px 1px 2px ${
-          isDarkMode ? 'rgba(0, 0, 0, 0.25)' : 'rgba(0, 0, 0, 0.1)'
-        };
-      }
-
-      .CustomSwitchIntroduction-thumb[data-state="checked"] {
-        left: 18px;
-        background-color: #fff;
-        box-shadow: 0px 1px 2px rgba(0, 0, 0, 0.3);
-      }
-    `}
-    </style>
-  );
-}
diff --git a/docs/data/components/switch/UnstyledSwitchIntroduction/css-modules/styles.module.css b/docs/data/components/switch/UnstyledSwitchIntroduction/css-modules/styles.module.css
new file mode 100644
index 0000000000..d0b25a5991
--- /dev/null
+++ b/docs/data/components/switch/UnstyledSwitchIntroduction/css-modules/styles.module.css
@@ -0,0 +1,80 @@
+.root {
+  width: 38px;
+  height: 24px;
+  margin: 10px;
+  padding: 0;
+  box-sizing: border-box;
+  background: var(--gray-50);
+  border: 1px solid var(--gray-200);
+  border-radius: 24px;
+  display: inline-block;
+  transition-property: all;
+  transition-timing-function: cubic-bezier(0.4, 0, 0.2, 1);
+  transition-duration: 120ms;
+  box-shadow: inset 0px 1px 1px rgba(0, 0, 0, 0.05);
+
+  :global(.dark) & {
+    background: var(--gray-900);
+    border-color: var(--gray-800);
+    box-shadow: inset 0px 1px 1px rgba(0, 0, 0, 0.5);
+  }
+
+  &[data-disabled] {
+    opacity: 0.4;
+    cursor: not-allowed;
+  }
+
+  &:hover:not([data-disabled]) {
+    background: var(--gray-100);
+    border-color: var(--gray-300);
+
+    :global(.dark) & {
+      background: var(--gray-800);
+      border-color: var(--gray-600);
+    }
+  }
+
+  &:focus-visible {
+    box-shadow: 0 0 0 3px var(--cyan-200);
+
+    :global(.dark) & {
+      box-shadow: 0 0 0 3px var(--cyan-700);
+    }
+  }
+
+  &[data-state='checked'] {
+    border: none;
+    background: var(--cyan-500);
+  }
+
+  &[data-state='checked']:not([data-disabled]):hover {
+    background: var(--cyan-700);
+  }
+}
+
+.thumb {
+  box-sizing: border-box;
+  border: 1px solid var(--gray-200);
+  display: block;
+  width: 16px;
+  height: 16px;
+  left: 4px;
+  border-radius: 16px;
+  background-color: #fff;
+  position: relative;
+  transition-property: all;
+  transition-timing-function: cubic-bezier(0.4, 0, 0.2, 1);
+  transition-duration: 120ms;
+  box-shadow: 0px 1px 2px rgba(0, 0, 0, 0.1);
+
+  :global(.dark) & {
+    border-color: var(--gray-800);
+    box-shadow: 0px 1px 2px rgba(0, 0, 0, 0.25);
+  }
+}
+
+.thumb[data-state='checked'] {
+  left: 18px;
+  background-color: #fff;
+  box-shadow: 0px 1px 2px rgba(0, 0, 0, 0.3);
+}
diff --git a/docs/data/components/switch/UnstyledSwitchIntroduction/tailwind/index.tsx b/docs/data/components/switch/UnstyledSwitchIntroduction/tailwind/index.tsx
index f7443c9756..d3c6a6a13f 100644
--- a/docs/data/components/switch/UnstyledSwitchIntroduction/tailwind/index.tsx
+++ b/docs/data/components/switch/UnstyledSwitchIntroduction/tailwind/index.tsx
@@ -30,9 +30,9 @@ export default function UnstyledSwitchIntroduction() {
   );
 }
 
-const Switch = React.forwardRef<HTMLButtonElement, BaseSwitch.RootProps>(
+const Switch = React.forwardRef<HTMLButtonElement, BaseSwitch.Root.Props>(
   function Switch({ className: classNameProp = '', ...props }, ref) {
-    const className = ({ checked }: BaseSwitch.OwnerState) =>
+    const className = ({ checked }: BaseSwitch.Root.OwnerState) =>
       `group relative inline-block w-[38px] h-[24px] m-2.5 p-0 transition rounded-full
     border border-solid outline-none border-slate-300 dark:border-gray-700
     focus-visible:shadow-outline-switch
@@ -48,7 +48,7 @@ const Thumb = React.forwardRef<
   HTMLSpanElement,
   React.HTMLAttributes<HTMLSpanElement>
 >(function Thumb({ className: classNameProp = '', ...props }, ref) {
-  const className = ({ checked }: BaseSwitch.OwnerState) =>
+  const className = ({ checked }: BaseSwitch.Root.OwnerState) =>
     `block w-4 h-4 rounded-2xl border border-solid outline-none border-slate-300 dark:border-gray-700 transition
   shadow-[0_1px_2px_rgb(0_0_0_/_0.1)] dark:shadow-[0_1px_2px_rgb(0_0_0_/_0.25)]
   relative transition-all
diff --git a/docs/data/translations/api-docs/switch-root/switch-root.json b/docs/data/translations/api-docs/switch-root/switch-root.json
index 36b79335c1..401676fbbc 100644
--- a/docs/data/translations/api-docs/switch-root/switch-root.json
+++ b/docs/data/translations/api-docs/switch-root/switch-root.json
@@ -11,7 +11,6 @@
     "disabled": {
       "description": "If <code>true</code>, the component is disabled and can&#39;t be interacted with."
     },
-    "id": { "description": "The id of the switch element." },
     "inputRef": { "description": "Ref to the underlying input element." },
     "name": { "description": "Name of the underlying input element." },
     "onCheckedChange": {
diff --git a/packages/mui-base/src/Switch/Root/SwitchContext.ts b/packages/mui-base/src/Switch/Root/SwitchContext.ts
deleted file mode 100644
index c2366b6127..0000000000
--- a/packages/mui-base/src/Switch/Root/SwitchContext.ts
+++ /dev/null
@@ -1,5 +0,0 @@
-'use client';
-import * as React from 'react';
-import { type SwitchOwnerState } from './SwitchRoot.types';
-
-export const SwitchContext = React.createContext<SwitchOwnerState | null>(null);
diff --git a/packages/mui-base/src/Switch/Root/SwitchRoot.tsx b/packages/mui-base/src/Switch/Root/SwitchRoot.tsx
index f467e55059..0c72e0152d 100644
--- a/packages/mui-base/src/Switch/Root/SwitchRoot.tsx
+++ b/packages/mui-base/src/Switch/Root/SwitchRoot.tsx
@@ -3,17 +3,12 @@ import * as React from 'react';
 import PropTypes from 'prop-types';
 import refType from '@mui/utils/refType';
 import { useSwitchRoot } from './useSwitchRoot';
-import { SwitchContext } from './SwitchContext';
-import type { SwitchRootProps, SwitchOwnerState } from './SwitchRoot.types';
-import { resolveClassName } from '../../utils/resolveClassName';
-import { useSwitchStyleHooks } from './useSwitchStyleHooks';
-import { evaluateRenderProp } from '../../utils/evaluateRenderProp';
-import { useRenderPropForkRef } from '../../utils/useRenderPropForkRef';
+import { SwitchRootContext } from './SwitchRootContext';
+import { styleHookMapping } from '../styleHooks';
+import { useComponentRenderer } from '../../utils/useComponentRenderer';
 import { useFieldRootContext } from '../../Field/Root/FieldRootContext';
-
-function defaultRender(props: React.ComponentPropsWithRef<'button'>) {
-  return <button type="button" {...props} />;
-}
+import type { BaseUIComponentProps } from '../../utils/types';
+import type { FieldRootOwnerState } from '../../Field/Root/FieldRoot.types';
 
 /**
  * The foundation for building custom-styled switches.
@@ -27,29 +22,28 @@ function defaultRender(props: React.ComponentPropsWithRef<'button'>) {
  * - [SwitchRoot API](https://base-ui.netlify.app/components/react-switch/#api-reference-SwitchRoot)
  */
 const SwitchRoot = React.forwardRef(function SwitchRoot(
-  props: SwitchRootProps,
+  props: SwitchRoot.Props,
   forwardedRef: React.ForwardedRef<HTMLButtonElement>,
 ) {
   const {
     checked: checkedProp,
-    className: classNameProp,
+    className,
     defaultChecked,
     inputRef,
     onCheckedChange,
     readOnly = false,
     required = false,
     disabled: disabledProp = false,
-    render: renderProp,
+    render,
     ...other
   } = props;
-  const render = renderProp ?? defaultRender;
 
   const { getInputProps, getButtonProps, checked } = useSwitchRoot(props);
 
   const { ownerState: fieldOwnerState, disabled: fieldDisabled } = useFieldRootContext();
   const disabled = fieldDisabled || disabledProp;
 
-  const ownerState: SwitchOwnerState = React.useMemo(
+  const ownerState: SwitchRoot.OwnerState = React.useMemo(
     () => ({
       ...fieldOwnerState,
       checked,
@@ -60,26 +54,38 @@ const SwitchRoot = React.forwardRef(function SwitchRoot(
     [fieldOwnerState, checked, disabled, readOnly, required],
   );
 
-  const className = resolveClassName(classNameProp, ownerState);
-  const styleHooks = useSwitchStyleHooks(ownerState);
-  const mergedRef = useRenderPropForkRef(render, forwardedRef);
-
-  const buttonProps = {
+  const { renderElement } = useComponentRenderer({
+    render: render || 'button',
     className,
-    ref: mergedRef,
-    ...styleHooks,
-    ...other,
-  };
+    propGetter: getButtonProps,
+    ownerState,
+    extraProps: other,
+    customStyleHookMapping: styleHookMapping,
+    ref: forwardedRef,
+  });
 
   return (
-    <SwitchContext.Provider value={ownerState}>
-      {evaluateRenderProp(render, getButtonProps(buttonProps), ownerState)}
+    <SwitchRootContext.Provider value={ownerState}>
+      {renderElement()}
       {!checked && props.name && <input type="hidden" name={props.name} value="off" />}
       <input {...getInputProps()} />
-    </SwitchContext.Provider>
+    </SwitchRootContext.Provider>
   );
 });
 
+namespace SwitchRoot {
+  export interface Props
+    extends useSwitchRoot.Parameters,
+      Omit<BaseUIComponentProps<'button', SwitchRoot.OwnerState>, 'onChange'> {}
+
+  export interface OwnerState extends FieldRootOwnerState {
+    checked: boolean;
+    disabled: boolean;
+    readOnly: boolean;
+    required: boolean;
+  }
+}
+
 SwitchRoot.propTypes /* remove-proptypes */ = {
   // ┌────────────────────────────── Warning ──────────────────────────────┐
   // │ These PropTypes are generated from the TypeScript type definitions. │
@@ -107,10 +113,6 @@ SwitchRoot.propTypes /* remove-proptypes */ = {
    * @default false
    */
   disabled: PropTypes.bool,
-  /**
-   * The id of the switch element.
-   */
-  id: PropTypes.string,
   /**
    * Ref to the underlying input element.
    */
diff --git a/packages/mui-base/src/Switch/Root/SwitchRoot.types.ts b/packages/mui-base/src/Switch/Root/SwitchRoot.types.ts
deleted file mode 100644
index 00ac074764..0000000000
--- a/packages/mui-base/src/Switch/Root/SwitchRoot.types.ts
+++ /dev/null
@@ -1,87 +0,0 @@
-import type * as React from 'react';
-import type { BaseUIComponentProps } from '../../utils/types';
-import type { FieldRootOwnerState } from '../../Field/Root/FieldRoot.types';
-
-export interface SwitchOwnerState extends FieldRootOwnerState {
-  checked: boolean;
-  disabled: boolean;
-  readOnly: boolean;
-  required: boolean;
-}
-
-export interface SwitchRootProps
-  extends UseSwitchRootParameters,
-    Omit<BaseUIComponentProps<'button', SwitchOwnerState>, 'onChange'> {}
-
-export type SwitchContextValue = SwitchOwnerState;
-
-export interface UseSwitchRootParameters {
-  /**
-   * The id of the switch element.
-   */
-  id?: string;
-  /**
-   * If `true`, the switch is checked.
-   */
-  checked?: boolean;
-  /**
-   * The default checked state. Use when the component is not controlled.
-   */
-  defaultChecked?: boolean;
-  /**
-   * If `true`, the component is disabled and can't be interacted with.
-   *
-   * @default false
-   */
-  disabled?: boolean;
-  /**
-   * Ref to the underlying input element.
-   */
-  inputRef?: React.Ref<HTMLInputElement>;
-  /**
-   * Name of the underlying input element.
-   */
-  name?: string;
-  /**
-   * Callback fired when the checked state is changed.
-   *
-   * @param {boolean} checked The new checked state.
-   * @param {React.ChangeEvent<HTMLInputElement>} event The event source of the callback.
-   */
-  onCheckedChange?: (checked: boolean, event: React.ChangeEvent<HTMLInputElement>) => void;
-  /**
-   * If `true`, the component is read-only.
-   * Functionally, this is equivalent to being disabled, but the assistive technologies will announce this differently.
-   *
-   * @default false
-   */
-  readOnly?: boolean;
-  /**
-   * If `true`, the switch must be checked for the browser validation to pass.
-   *
-   * @default false
-   */
-  required?: boolean;
-}
-export interface UseSwitchRootReturnValue {
-  /**
-   * If `true`, the component will be checked.
-   */
-  checked: boolean;
-  /**
-   * Resolver for the input element's props.
-   * @param externalProps Additional props for the input element
-   * @returns Props that should be spread on the input element
-   */
-  getInputProps: (
-    externalProps?: React.ComponentPropsWithRef<'input'>,
-  ) => React.ComponentPropsWithRef<'input'>;
-  /**
-   * Resolver for the button element's props.
-   * @param externalProps Additional props for the input element
-   * @returns Props that should be spread on the button element
-   */
-  getButtonProps: (
-    externalProps?: React.ComponentPropsWithRef<'button'>,
-  ) => React.ComponentPropsWithRef<'button'>;
-}
diff --git a/packages/mui-base/src/Switch/Root/SwitchRootContext.ts b/packages/mui-base/src/Switch/Root/SwitchRootContext.ts
new file mode 100644
index 0000000000..3804b912d4
--- /dev/null
+++ b/packages/mui-base/src/Switch/Root/SwitchRootContext.ts
@@ -0,0 +1,15 @@
+import * as React from 'react';
+import type { SwitchRoot } from './SwitchRoot';
+
+export type SwitchRootContext = SwitchRoot.OwnerState;
+
+export const SwitchRootContext = React.createContext<SwitchRootContext | undefined>(undefined);
+
+export function useSwitchRootContext() {
+  const context = React.useContext(SwitchRootContext);
+  if (context === undefined) {
+    throw new Error('useSwitchRootContext must be used within a SwitchRootProvider');
+  }
+
+  return context;
+}
diff --git a/packages/mui-base/src/Switch/Root/useSwitchRoot.ts b/packages/mui-base/src/Switch/Root/useSwitchRoot.ts
index 555755f838..6cec0e60d5 100644
--- a/packages/mui-base/src/Switch/Root/useSwitchRoot.ts
+++ b/packages/mui-base/src/Switch/Root/useSwitchRoot.ts
@@ -1,6 +1,5 @@
 'use client';
 import * as React from 'react';
-import type { UseSwitchRootParameters, UseSwitchRootReturnValue } from './SwitchRoot.types';
 import { useControlled } from '../../utils/useControlled';
 import { useForkRef } from '../../utils/useForkRef';
 import { visuallyHidden } from '../../utils/visuallyHidden';
@@ -12,18 +11,7 @@ import { useEnhancedEffect } from '../../utils/useEnhancedEffect';
 import { useFieldControlValidation } from '../../Field/Control/useFieldControlValidation';
 import { useField } from '../../Field/useField';
 
-/**
- * The basic building block for creating custom switches.
- *
- * Demos:
- *
- * - [Switch](https://mui.com/base-ui/react-switch/#hook)
- *
- * API:
- *
- * - [useSwitchRoot API](https://mui.com/base-ui/react-switch/hooks-api/#use-switch-root)
- */
-export function useSwitchRoot(params: UseSwitchRootParameters): UseSwitchRootReturnValue {
+export function useSwitchRoot(params: useSwitchRoot.Parameters): useSwitchRoot.ReturnValue {
   const {
     id: idProp,
     checked: checkedProp,
@@ -154,3 +142,77 @@ export function useSwitchRoot(params: UseSwitchRootParameters): UseSwitchRootRet
     [checked, getButtonProps, getInputProps],
   );
 }
+
+export namespace useSwitchRoot {
+  export interface Parameters {
+    /**
+     * The id of the switch element.
+     */
+    id?: string;
+    /**
+     * If `true`, the switch is checked.
+     */
+    checked?: boolean;
+    /**
+     * The default checked state. Use when the component is not controlled.
+     */
+    defaultChecked?: boolean;
+    /**
+     * If `true`, the component is disabled and can't be interacted with.
+     *
+     * @default false
+     */
+    disabled?: boolean;
+    /**
+     * Ref to the underlying input element.
+     */
+    inputRef?: React.Ref<HTMLInputElement>;
+    /**
+     * Name of the underlying input element.
+     */
+    name?: string;
+    /**
+     * Callback fired when the checked state is changed.
+     *
+     * @param {boolean} checked The new checked state.
+     * @param {React.ChangeEvent<HTMLInputElement>} event The event source of the callback.
+     */
+    onCheckedChange?: (checked: boolean, event: React.ChangeEvent<HTMLInputElement>) => void;
+    /**
+     * If `true`, the component is read-only.
+     * Functionally, this is equivalent to being disabled, but the assistive technologies will announce this differently.
+     *
+     * @default false
+     */
+    readOnly?: boolean;
+    /**
+     * If `true`, the switch must be checked for the browser validation to pass.
+     *
+     * @default false
+     */
+    required?: boolean;
+  }
+
+  export interface ReturnValue {
+    /**
+     * If `true`, the component will be checked.
+     */
+    checked: boolean;
+    /**
+     * Resolver for the input element's props.
+     * @param externalProps Additional props for the input element
+     * @returns Props that should be spread on the input element
+     */
+    getInputProps: (
+      externalProps?: React.ComponentPropsWithRef<'input'>,
+    ) => React.ComponentPropsWithRef<'input'>;
+    /**
+     * Resolver for the button element's props.
+     * @param externalProps Additional props for the input element
+     * @returns Props that should be spread on the button element
+     */
+    getButtonProps: (
+      externalProps?: React.ComponentPropsWithRef<'button'>,
+    ) => React.ComponentPropsWithRef<'button'>;
+  }
+}
diff --git a/packages/mui-base/src/Switch/Root/useSwitchStyleHooks.ts b/packages/mui-base/src/Switch/Root/useSwitchStyleHooks.ts
deleted file mode 100644
index 885b5c9cb4..0000000000
--- a/packages/mui-base/src/Switch/Root/useSwitchStyleHooks.ts
+++ /dev/null
@@ -1,14 +0,0 @@
-import * as React from 'react';
-import { SwitchOwnerState } from './SwitchRoot.types';
-import { getStyleHookProps } from '../../utils/getStyleHookProps';
-
-/**
- * @ignore - internal hook.
- */
-export function useSwitchStyleHooks(ownerState: SwitchOwnerState) {
-  return React.useMemo(() => {
-    return getStyleHookProps(ownerState, {
-      checked: (value) => ({ 'data-state': value ? 'checked' : 'unchecked' }),
-    });
-  }, [ownerState]);
-}
diff --git a/packages/mui-base/src/Switch/Thumb/SwitchThumb.test.tsx b/packages/mui-base/src/Switch/Thumb/SwitchThumb.test.tsx
index 4db313f8f2..9e49e094b7 100644
--- a/packages/mui-base/src/Switch/Thumb/SwitchThumb.test.tsx
+++ b/packages/mui-base/src/Switch/Thumb/SwitchThumb.test.tsx
@@ -1,9 +1,9 @@
 import * as React from 'react';
 import * as Switch from '@base_ui/react/Switch';
 import { createRenderer, describeConformance } from '#test-utils';
-import { SwitchContext } from '../Root/SwitchContext';
+import { SwitchRootContext } from '../Root/SwitchRootContext';
 
-const testContext = {
+const testContext: SwitchRootContext = {
   checked: false,
   disabled: false,
   readOnly: false,
@@ -19,7 +19,9 @@ describe('<Switch.Thumb />', () => {
   describeConformance(<Switch.Thumb />, () => ({
     refInstanceof: window.HTMLSpanElement,
     render: (node) => {
-      return render(<SwitchContext.Provider value={testContext}>{node}</SwitchContext.Provider>);
+      return render(
+        <SwitchRootContext.Provider value={testContext}>{node}</SwitchRootContext.Provider>,
+      );
     },
   }));
 });
diff --git a/packages/mui-base/src/Switch/Thumb/SwitchThumb.tsx b/packages/mui-base/src/Switch/Thumb/SwitchThumb.tsx
index 078b49daee..831ee3c0e2 100644
--- a/packages/mui-base/src/Switch/Thumb/SwitchThumb.tsx
+++ b/packages/mui-base/src/Switch/Thumb/SwitchThumb.tsx
@@ -1,17 +1,12 @@
 'use client';
 import * as React from 'react';
 import PropTypes from 'prop-types';
-import { SwitchThumbProps } from './SwitchThumb.types';
-import { SwitchContext } from '../Root/SwitchContext';
-import { useSwitchStyleHooks } from '../Root/useSwitchStyleHooks';
-import { resolveClassName } from '../../utils/resolveClassName';
-import { evaluateRenderProp } from '../../utils/evaluateRenderProp';
-import { useRenderPropForkRef } from '../../utils/useRenderPropForkRef';
+import type { SwitchRoot } from '../Root/SwitchRoot';
+import { useSwitchRootContext } from '../Root/SwitchRootContext';
+import { useComponentRenderer } from '../../utils/useComponentRenderer';
 import { useFieldRootContext } from '../../Field/Root/FieldRootContext';
-
-function defaultRender(props: React.ComponentPropsWithRef<'span'>) {
-  return <span {...props} />;
-}
+import type { BaseUIComponentProps } from '../../utils/types';
+import { styleHookMapping } from '../styleHooks';
 
 /**
  *
@@ -24,35 +19,34 @@ function defaultRender(props: React.ComponentPropsWithRef<'span'>) {
  * - [SwitchThumb API](https://base-ui.netlify.app/components/react-switch/#api-reference-SwitchThumb)
  */
 const SwitchThumb = React.forwardRef(function SwitchThumb(
-  props: SwitchThumbProps,
+  props: SwitchThumb.Props,
   forwardedRef: React.ForwardedRef<HTMLSpanElement>,
 ) {
-  const { render: renderProp, className: classNameProp, ...other } = props;
-  const render = renderProp ?? defaultRender;
+  const { render, className, ...other } = props;
 
   const { ownerState: fieldOwnerState } = useFieldRootContext();
 
-  const ownerState = React.useContext(SwitchContext);
-  if (ownerState === null) {
-    throw new Error('Base UI: Switch.Thumb is not placed inside the Switch component.');
-  }
-
+  const ownerState = useSwitchRootContext();
   const extendedOwnerState = { ...fieldOwnerState, ...ownerState };
 
-  const className = resolveClassName(classNameProp, extendedOwnerState);
-  const styleHooks = useSwitchStyleHooks(extendedOwnerState);
-  const mergedRef = useRenderPropForkRef(render, forwardedRef);
-
-  const elementProps = {
+  const { renderElement } = useComponentRenderer({
+    render: render || 'span',
     className,
-    ref: mergedRef,
-    ...styleHooks,
-    ...other,
-  };
+    ownerState: extendedOwnerState,
+    extraProps: other,
+    customStyleHookMapping: styleHookMapping,
+    ref: forwardedRef,
+  });
 
-  return evaluateRenderProp(render, elementProps, ownerState);
+  return renderElement();
 });
 
+namespace SwitchThumb {
+  export interface Props extends BaseUIComponentProps<'span', OwnerState> {}
+
+  export interface OwnerState extends SwitchRoot.OwnerState {}
+}
+
 SwitchThumb.propTypes /* remove-proptypes */ = {
   // ┌────────────────────────────── Warning ──────────────────────────────┐
   // │ These PropTypes are generated from the TypeScript type definitions. │
diff --git a/packages/mui-base/src/Switch/Thumb/SwitchThumb.types.ts b/packages/mui-base/src/Switch/Thumb/SwitchThumb.types.ts
deleted file mode 100644
index 51d55535b3..0000000000
--- a/packages/mui-base/src/Switch/Thumb/SwitchThumb.types.ts
+++ /dev/null
@@ -1,4 +0,0 @@
-import type { SwitchOwnerState } from '../Root/SwitchRoot.types';
-import type { BaseUIComponentProps } from '../../utils/types';
-
-export interface SwitchThumbProps extends BaseUIComponentProps<'span', SwitchOwnerState> {}
diff --git a/packages/mui-base/src/Switch/index.barrel.ts b/packages/mui-base/src/Switch/index.barrel.ts
index f4f136cf88..f717fab5ad 100644
--- a/packages/mui-base/src/Switch/index.barrel.ts
+++ b/packages/mui-base/src/Switch/index.barrel.ts
@@ -1,13 +1,2 @@
 export { SwitchRoot } from './Root/SwitchRoot';
-export { useSwitchRoot } from './Root/useSwitchRoot';
-export { SwitchContext } from './Root/SwitchContext';
-export type {
-  SwitchRootProps,
-  SwitchOwnerState,
-  SwitchContextValue,
-  UseSwitchRootParameters,
-  UseSwitchRootReturnValue,
-} from './Root/SwitchRoot.types';
-
 export { SwitchThumb } from './Thumb/SwitchThumb';
-export type { SwitchThumbProps } from './Thumb/SwitchThumb.types';
diff --git a/packages/mui-base/src/Switch/index.ts b/packages/mui-base/src/Switch/index.ts
index d033156fdf..7edb4a4336 100644
--- a/packages/mui-base/src/Switch/index.ts
+++ b/packages/mui-base/src/Switch/index.ts
@@ -1,13 +1,2 @@
 export { SwitchRoot as Root } from './Root/SwitchRoot';
-export { useSwitchRoot } from './Root/useSwitchRoot';
-export { SwitchContext } from './Root/SwitchContext';
-export type {
-  SwitchRootProps as RootProps,
-  SwitchOwnerState as OwnerState,
-  SwitchContextValue,
-  UseSwitchRootParameters,
-  UseSwitchRootReturnValue,
-} from './Root/SwitchRoot.types';
-
 export { SwitchThumb as Thumb } from './Thumb/SwitchThumb';
-export type { SwitchThumbProps as ThumbProps } from './Thumb/SwitchThumb.types';
diff --git a/packages/mui-base/src/Switch/styleHooks.ts b/packages/mui-base/src/Switch/styleHooks.ts
new file mode 100644
index 0000000000..0c8fd40aba
--- /dev/null
+++ b/packages/mui-base/src/Switch/styleHooks.ts
@@ -0,0 +1,6 @@
+import type { SwitchRoot } from './Root/SwitchRoot';
+import type { CustomStyleHookMapping } from '../utils/getStyleHookProps';
+
+export const styleHookMapping: CustomStyleHookMapping<SwitchRoot.OwnerState> = {
+  checked: (value) => ({ 'data-state': value ? 'checked' : 'unchecked' }),
+};

From b968150b759762a0d5302a0e3a908984decd1348 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Dudak?= <michal@mui.com>
Date: Mon, 7 Oct 2024 11:23:00 +0200
Subject: [PATCH 3/4] [Tabs] Move types to namespaces (#642)

---
 .../tailwind/index.tsx                        |  6 +-
 .../PackageManagerSnippetRoot.tsx             |  4 +-
 .../mui-base/src/Tabs/Root/TabsProvider.tsx   |  8 +-
 .../mui-base/src/Tabs/Root/TabsRoot.test.tsx  | 40 ++++-----
 packages/mui-base/src/Tabs/Root/TabsRoot.tsx  | 44 ++++++++-
 .../mui-base/src/Tabs/Root/TabsRoot.types.ts  | 78 ----------------
 .../{TabsContext.ts => TabsRootContext.ts}    | 16 ++--
 packages/mui-base/src/Tabs/Root/styleHooks.ts |  4 +-
 .../mui-base/src/Tabs/Root/useTabsRoot.ts     | 51 +++++++++--
 packages/mui-base/src/Tabs/Tab/Tab.test.tsx   | 14 ++-
 packages/mui-base/src/Tabs/Tab/Tab.tsx        | 22 ++++-
 packages/mui-base/src/Tabs/Tab/Tab.types.ts   | 71 ---------------
 packages/mui-base/src/Tabs/Tab/useTab.ts      | 65 +++++++++++++-
 .../src/Tabs/TabIndicator/TabIndicator.tsx    | 31 +++++--
 .../Tabs/TabIndicator/TabIndicator.types.ts   | 40 ---------
 .../src/Tabs/TabIndicator/useTabIndicator.ts  | 27 +++++-
 .../src/Tabs/TabPanel/TabPanel.test.tsx       |  2 +-
 .../mui-base/src/Tabs/TabPanel/TabPanel.tsx   | 27 +++++-
 .../src/Tabs/TabPanel/TabPanel.types.ts       | 59 ------------
 .../src/Tabs/TabPanel/useTabPanel.test.tsx    |  5 +-
 .../mui-base/src/Tabs/TabPanel/useTabPanel.ts | 44 ++++++++-
 .../src/Tabs/TabsList/TabsList.test.tsx       |  6 +-
 .../mui-base/src/Tabs/TabsList/TabsList.tsx   | 27 +++++-
 .../src/Tabs/TabsList/TabsList.types.ts       | 90 -------------------
 .../src/Tabs/TabsList/TabsListContext.ts      |  6 +-
 .../src/Tabs/TabsList/TabsListProvider.tsx    |  6 +-
 .../src/Tabs/TabsList/tabsListReducer.ts      | 10 ++-
 .../mui-base/src/Tabs/TabsList/useTabsList.ts | 76 +++++++++++++---
 packages/mui-base/src/Tabs/index.barrel.ts    | 38 --------
 packages/mui-base/src/Tabs/index.ts           | 38 --------
 30 files changed, 430 insertions(+), 525 deletions(-)
 delete mode 100644 packages/mui-base/src/Tabs/Root/TabsRoot.types.ts
 rename packages/mui-base/src/Tabs/Root/{TabsContext.ts => TabsRootContext.ts} (76%)
 delete mode 100644 packages/mui-base/src/Tabs/Tab/Tab.types.ts
 delete mode 100644 packages/mui-base/src/Tabs/TabIndicator/TabIndicator.types.ts
 delete mode 100644 packages/mui-base/src/Tabs/TabPanel/TabPanel.types.ts
 delete mode 100644 packages/mui-base/src/Tabs/TabsList/TabsList.types.ts

diff --git a/docs/data/components/tabs/UnstyledTabsIntroduction/tailwind/index.tsx b/docs/data/components/tabs/UnstyledTabsIntroduction/tailwind/index.tsx
index 4eb2e98f54..92957ad454 100644
--- a/docs/data/components/tabs/UnstyledTabsIntroduction/tailwind/index.tsx
+++ b/docs/data/components/tabs/UnstyledTabsIntroduction/tailwind/index.tsx
@@ -29,7 +29,7 @@ export default function UnstyledTabsIntroduction() {
   );
 }
 
-const TabsList = React.forwardRef<HTMLDivElement, Tabs.ListProps>((props, ref) => {
+const TabsList = React.forwardRef<HTMLDivElement, Tabs.List.Props>((props, ref) => {
   const { className, ...other } = props;
   return (
     <Tabs.List
@@ -43,7 +43,7 @@ const TabsList = React.forwardRef<HTMLDivElement, Tabs.ListProps>((props, ref) =
   );
 });
 
-const Tab = React.forwardRef<HTMLButtonElement, Tabs.TabProps>((props, ref) => {
+const Tab = React.forwardRef<HTMLButtonElement, Tabs.Tab.Props>((props, ref) => {
   const { className, ...other } = props;
   return (
     <Tabs.Tab
@@ -65,7 +65,7 @@ const Tab = React.forwardRef<HTMLButtonElement, Tabs.TabProps>((props, ref) => {
   );
 });
 
-const TabPanel = React.forwardRef<HTMLDivElement, Tabs.PanelProps>((props, ref) => {
+const TabPanel = React.forwardRef<HTMLDivElement, Tabs.Panel.Props>((props, ref) => {
   const { className, ...other } = props;
   return (
     <Tabs.Panel
diff --git a/docs/src/blocks/PackageManagerSnippet/PackageManagerSnippetRoot.tsx b/docs/src/blocks/PackageManagerSnippet/PackageManagerSnippetRoot.tsx
index eae7177cd5..a9d8e6c234 100644
--- a/docs/src/blocks/PackageManagerSnippet/PackageManagerSnippetRoot.tsx
+++ b/docs/src/blocks/PackageManagerSnippet/PackageManagerSnippetRoot.tsx
@@ -44,7 +44,7 @@ export namespace PackageManagerSnippetRoot {
   export type Props = {
     children: React.ReactNode;
     options: Array<{ value: string; label: string }>;
-    renderTab?: Tabs.TabProps['render'];
-    renderTabsList?: Tabs.ListProps['render'];
+    renderTab?: Tabs.Tab.Props['render'];
+    renderTabsList?: Tabs.List.Props['render'];
   };
 }
diff --git a/packages/mui-base/src/Tabs/Root/TabsProvider.tsx b/packages/mui-base/src/Tabs/Root/TabsProvider.tsx
index fdef97885f..2a6670b7ad 100644
--- a/packages/mui-base/src/Tabs/Root/TabsProvider.tsx
+++ b/packages/mui-base/src/Tabs/Root/TabsProvider.tsx
@@ -1,7 +1,7 @@
 'use client';
 import * as React from 'react';
 import PropTypes from 'prop-types';
-import { TabsContext, TabsContextValue } from './TabsContext';
+import { TabsRootContext } from './TabsRootContext';
 import { CompoundComponentContext, CompoundComponentContextValue } from '../../useCompound';
 
 export type TabPanelMetadata = {
@@ -10,7 +10,7 @@ export type TabPanelMetadata = {
 };
 
 export type TabsProviderValue = CompoundComponentContextValue<any, TabPanelMetadata> &
-  TabsContextValue;
+  TabsRootContext;
 
 export interface TabsProviderProps {
   value: TabsProviderValue;
@@ -48,7 +48,7 @@ function TabsProvider(props: TabsProviderProps) {
       [registerItem, getItemIndex, totalSubitemCount],
     );
 
-  const tabsContextValue: TabsContextValue = React.useMemo(
+  const tabsContextValue: TabsRootContext = React.useMemo(
     () => ({
       direction,
       getTabId,
@@ -73,7 +73,7 @@ function TabsProvider(props: TabsProviderProps) {
 
   return (
     <CompoundComponentContext.Provider value={compoundComponentContextValue}>
-      <TabsContext.Provider value={tabsContextValue}>{children}</TabsContext.Provider>
+      <TabsRootContext.Provider value={tabsContextValue}>{children}</TabsRootContext.Provider>
     </CompoundComponentContext.Provider>
   );
 }
diff --git a/packages/mui-base/src/Tabs/Root/TabsRoot.test.tsx b/packages/mui-base/src/Tabs/Root/TabsRoot.test.tsx
index 18c46cc3fa..00e145932b 100644
--- a/packages/mui-base/src/Tabs/Root/TabsRoot.test.tsx
+++ b/packages/mui-base/src/Tabs/Root/TabsRoot.test.tsx
@@ -280,10 +280,10 @@ describe('<Tabs.Root />', () => {
               const handleKeyDown = spy();
               const { getAllByRole } = await render(
                 <Tabs.Root
-                  direction={direction as Tabs.RootProps['direction']}
+                  direction={direction as Tabs.Root.Props['direction']}
                   onValueChange={handleChange}
                   onKeyDown={handleKeyDown}
-                  orientation={orientation as Tabs.RootProps['orientation']}
+                  orientation={orientation as Tabs.Root.Props['orientation']}
                   value={0}
                 >
                   <Tabs.List activateOnFocus={false}>
@@ -311,10 +311,10 @@ describe('<Tabs.Root />', () => {
               const handleKeyDown = spy();
               const { getAllByRole } = await render(
                 <Tabs.Root
-                  direction={direction as Tabs.RootProps['direction']}
+                  direction={direction as Tabs.Root.Props['direction']}
                   onValueChange={handleChange}
                   onKeyDown={handleKeyDown}
-                  orientation={orientation as Tabs.RootProps['orientation']}
+                  orientation={orientation as Tabs.Root.Props['orientation']}
                   value={1}
                 >
                   <Tabs.List activateOnFocus={false}>
@@ -344,10 +344,10 @@ describe('<Tabs.Root />', () => {
               const handleKeyDown = spy();
               const { getAllByRole } = await render(
                 <Tabs.Root
-                  direction={direction as Tabs.RootProps['direction']}
+                  direction={direction as Tabs.Root.Props['direction']}
                   onValueChange={handleChange}
                   onKeyDown={handleKeyDown}
-                  orientation={orientation as Tabs.RootProps['orientation']}
+                  orientation={orientation as Tabs.Root.Props['orientation']}
                   value={0}
                 >
                   <Tabs.List>
@@ -376,10 +376,10 @@ describe('<Tabs.Root />', () => {
               const handleKeyDown = spy();
               const { getAllByRole } = await render(
                 <Tabs.Root
-                  direction={direction as Tabs.RootProps['direction']}
+                  direction={direction as Tabs.Root.Props['direction']}
                   onValueChange={handleChange}
                   onKeyDown={handleKeyDown}
-                  orientation={orientation as Tabs.RootProps['orientation']}
+                  orientation={orientation as Tabs.Root.Props['orientation']}
                   value={1}
                 >
                   <Tabs.List>
@@ -408,9 +408,9 @@ describe('<Tabs.Root />', () => {
             const handleKeyDown = spy();
             const { getAllByRole } = await render(
               <Tabs.Root
-                direction={direction as Tabs.RootProps['direction']}
+                direction={direction as Tabs.Root.Props['direction']}
                 onKeyDown={handleKeyDown}
-                orientation={orientation as Tabs.RootProps['orientation']}
+                orientation={orientation as Tabs.Root.Props['orientation']}
                 value={2}
               >
                 <Tabs.List>
@@ -440,10 +440,10 @@ describe('<Tabs.Root />', () => {
               const handleKeyDown = spy();
               const { getAllByRole } = await render(
                 <Tabs.Root
-                  direction={direction as Tabs.RootProps['direction']}
+                  direction={direction as Tabs.Root.Props['direction']}
                   onValueChange={handleChange}
                   onKeyDown={handleKeyDown}
-                  orientation={orientation as Tabs.RootProps['orientation']}
+                  orientation={orientation as Tabs.Root.Props['orientation']}
                   value={2}
                 >
                   <Tabs.List activateOnFocus={false}>
@@ -471,10 +471,10 @@ describe('<Tabs.Root />', () => {
               const handleKeyDown = spy();
               const { getAllByRole } = await render(
                 <Tabs.Root
-                  direction={direction as Tabs.RootProps['direction']}
+                  direction={direction as Tabs.Root.Props['direction']}
                   onValueChange={handleChange}
                   onKeyDown={handleKeyDown}
-                  orientation={orientation as Tabs.RootProps['orientation']}
+                  orientation={orientation as Tabs.Root.Props['orientation']}
                   value={1}
                 >
                   <Tabs.List activateOnFocus={false}>
@@ -504,10 +504,10 @@ describe('<Tabs.Root />', () => {
               const handleKeyDown = spy();
               const { getAllByRole } = await render(
                 <Tabs.Root
-                  direction={direction as Tabs.RootProps['direction']}
+                  direction={direction as Tabs.Root.Props['direction']}
                   onValueChange={handleChange}
                   onKeyDown={handleKeyDown}
-                  orientation={orientation as Tabs.RootProps['orientation']}
+                  orientation={orientation as Tabs.Root.Props['orientation']}
                   value={2}
                 >
                   <Tabs.List>
@@ -536,10 +536,10 @@ describe('<Tabs.Root />', () => {
               const handleKeyDown = spy();
               const { getAllByRole } = await render(
                 <Tabs.Root
-                  direction={direction as Tabs.RootProps['direction']}
+                  direction={direction as Tabs.Root.Props['direction']}
                   onValueChange={handleChange}
                   onKeyDown={handleKeyDown}
-                  orientation={orientation as Tabs.RootProps['orientation']}
+                  orientation={orientation as Tabs.Root.Props['orientation']}
                   value={1}
                 >
                   <Tabs.List>
@@ -568,9 +568,9 @@ describe('<Tabs.Root />', () => {
             const handleKeyDown = spy();
             const { getAllByRole } = await render(
               <Tabs.Root
-                direction={direction as Tabs.RootProps['direction']}
+                direction={direction as Tabs.Root.Props['direction']}
                 onKeyDown={handleKeyDown}
-                orientation={orientation as Tabs.RootProps['orientation']}
+                orientation={orientation as Tabs.Root.Props['orientation']}
                 value={0}
               >
                 <Tabs.List>
diff --git a/packages/mui-base/src/Tabs/Root/TabsRoot.tsx b/packages/mui-base/src/Tabs/Root/TabsRoot.tsx
index 48ac80b66a..7660a562d1 100644
--- a/packages/mui-base/src/Tabs/Root/TabsRoot.tsx
+++ b/packages/mui-base/src/Tabs/Root/TabsRoot.tsx
@@ -1,11 +1,11 @@
 'use client';
 import * as React from 'react';
 import PropTypes from 'prop-types';
-import { TabsRootOwnerState, TabsRootProps } from './TabsRoot.types';
 import { useTabsRoot } from './useTabsRoot';
 import { tabsStyleHookMapping } from './styleHooks';
 import { TabsProvider } from './TabsProvider';
 import { useComponentRenderer } from '../../utils/useComponentRenderer';
+import type { BaseUIComponentProps } from '../../utils/types';
 
 /**
  *
@@ -18,7 +18,7 @@ import { useComponentRenderer } from '../../utils/useComponentRenderer';
  * - [TabsRoot API](https://base-ui.netlify.app/components/react-tabs/#api-reference-TabsRoot)
  */
 const TabsRoot = React.forwardRef(function TabsRoot(
-  props: TabsRootProps,
+  props: TabsRoot.Props,
   forwardedRef: React.ForwardedRef<HTMLDivElement>,
 ) {
   const {
@@ -40,7 +40,7 @@ const TabsRoot = React.forwardRef(function TabsRoot(
     direction,
   });
 
-  const ownerState: TabsRootOwnerState = {
+  const ownerState: TabsRoot.OwnerState = {
     orientation,
     direction,
     tabActivationDirection,
@@ -59,6 +59,44 @@ const TabsRoot = React.forwardRef(function TabsRoot(
   return <TabsProvider value={contextValue}>{renderElement()}</TabsProvider>;
 });
 
+export type TabsOrientation = 'horizontal' | 'vertical';
+export type TabsDirection = 'ltr' | 'rtl';
+export type TabActivationDirection = 'left' | 'right' | 'up' | 'down' | 'none';
+
+namespace TabsRoot {
+  export type OwnerState = {
+    orientation: TabsOrientation;
+    direction: TabsDirection;
+    tabActivationDirection: TabActivationDirection;
+  };
+
+  export interface Props extends BaseUIComponentProps<'div', OwnerState> {
+    /**
+     * The value of the currently selected `Tab`.
+     * If you don't want any selected `Tab`, you can set this prop to `null`.
+     */
+    value?: any | null;
+    /**
+     * The default value. Use when the component is not controlled.
+     */
+    defaultValue?: any | null;
+    /**
+     * The component orientation (layout flow direction).
+     * @default 'horizontal'
+     */
+    orientation?: TabsOrientation;
+    /**
+     * The direction of the text.
+     * @default 'ltr'
+     */
+    direction?: TabsDirection;
+    /**
+     * Callback invoked when new value is being set.
+     */
+    onValueChange?: (value: any | null, event: React.SyntheticEvent | null) => void;
+  }
+}
+
 TabsRoot.propTypes /* remove-proptypes */ = {
   // ┌────────────────────────────── Warning ──────────────────────────────┐
   // │ These PropTypes are generated from the TypeScript type definitions. │
diff --git a/packages/mui-base/src/Tabs/Root/TabsRoot.types.ts b/packages/mui-base/src/Tabs/Root/TabsRoot.types.ts
deleted file mode 100644
index cfb8dfa1e1..0000000000
--- a/packages/mui-base/src/Tabs/Root/TabsRoot.types.ts
+++ /dev/null
@@ -1,78 +0,0 @@
-import * as React from 'react';
-import { TabsProviderValue } from './TabsProvider';
-import { BaseUIComponentProps } from '../../utils/types';
-
-export type TabsRootOwnerState = {
-  orientation: TabsOrientation;
-  direction: TabsDirection;
-  tabActivationDirection: TabActivationDirection;
-};
-
-export interface TabsRootProps extends BaseUIComponentProps<'div', TabsRootOwnerState> {
-  /**
-   * The value of the currently selected `Tab`.
-   * If you don't want any selected `Tab`, you can set this prop to `null`.
-   */
-  value?: any | null;
-  /**
-   * The default value. Use when the component is not controlled.
-   */
-  defaultValue?: any | null;
-  /**
-   * The component orientation (layout flow direction).
-   * @default 'horizontal'
-   */
-  orientation?: TabsOrientation;
-  /**
-   * The direction of the text.
-   * @default 'ltr'
-   */
-  direction?: TabsDirection;
-  /**
-   * Callback invoked when new value is being set.
-   */
-  onValueChange?: (value: any | null, event: React.SyntheticEvent | null) => void;
-}
-
-export type TabActivationDirection = 'left' | 'right' | 'up' | 'down' | 'none';
-
-export type TabsOrientation = 'horizontal' | 'vertical';
-
-export type TabsDirection = 'ltr' | 'rtl';
-
-export interface UseTabsParameters {
-  /**
-   * The value of the currently selected `Tab`.
-   * If you don't want any selected `Tab`, you can set this prop to `false`.
-   */
-  value?: any | null;
-  /**
-   * The default value. Use when the component is not controlled.
-   */
-  defaultValue?: any | null;
-  /**
-   * The component orientation (layout flow direction).
-   * @default 'horizontal'
-   */
-  orientation?: 'horizontal' | 'vertical';
-  /**
-   * The direction of the text.
-   * @default 'ltr'
-   */
-  direction?: 'ltr' | 'rtl';
-  /**
-   * Callback invoked when new value is being set.
-   */
-  onValueChange?: (value: any | null, event: React.SyntheticEvent | null) => void;
-}
-
-export interface UseTabsReturnValue {
-  /**
-   * Returns the values to be passed to the tabs provider.
-   */
-  contextValue: TabsProviderValue;
-  getRootProps: (
-    externalProps?: React.ComponentPropsWithRef<'div'>,
-  ) => React.ComponentPropsWithRef<'div'>;
-  tabActivationDirection: TabActivationDirection;
-}
diff --git a/packages/mui-base/src/Tabs/Root/TabsContext.ts b/packages/mui-base/src/Tabs/Root/TabsRootContext.ts
similarity index 76%
rename from packages/mui-base/src/Tabs/Root/TabsContext.ts
rename to packages/mui-base/src/Tabs/Root/TabsRootContext.ts
index be0e02bc49..ea4d9101c9 100644
--- a/packages/mui-base/src/Tabs/Root/TabsContext.ts
+++ b/packages/mui-base/src/Tabs/Root/TabsRootContext.ts
@@ -1,8 +1,8 @@
 'use client';
 import * as React from 'react';
-import { type TabActivationDirection } from './TabsRoot.types';
+import { type TabActivationDirection } from './TabsRoot';
 
-export interface TabsContextValue {
+export interface TabsRootContext {
   /**
    * The currently selected tab's value.
    */
@@ -46,19 +46,19 @@ export interface TabsContextValue {
 /**
  * @ignore - internal component.
  */
-const TabsContext = React.createContext<TabsContextValue | null>(null);
+const TabsRootContext = React.createContext<TabsRootContext | null>(null);
 
 if (process.env.NODE_ENV !== 'production') {
-  TabsContext.displayName = 'TabsContext';
+  TabsRootContext.displayName = 'TabsRootContext';
 }
 
-export function useTabsContext() {
-  const context = React.useContext(TabsContext);
+export function useTabsRootContext() {
+  const context = React.useContext(TabsRootContext);
   if (context == null) {
-    throw new Error('No TabsContext provided');
+    throw new Error('Base UI: No TabsRootContext provided');
   }
 
   return context;
 }
 
-export { TabsContext };
+export { TabsRootContext };
diff --git a/packages/mui-base/src/Tabs/Root/styleHooks.ts b/packages/mui-base/src/Tabs/Root/styleHooks.ts
index 56883ad061..0e9a3c4fb3 100644
--- a/packages/mui-base/src/Tabs/Root/styleHooks.ts
+++ b/packages/mui-base/src/Tabs/Root/styleHooks.ts
@@ -1,7 +1,7 @@
-import type { TabsRootOwnerState } from './TabsRoot.types';
+import type { TabsRoot } from './TabsRoot';
 import type { CustomStyleHookMapping } from '../../utils/getStyleHookProps';
 
-export const tabsStyleHookMapping: CustomStyleHookMapping<TabsRootOwnerState> = {
+export const tabsStyleHookMapping: CustomStyleHookMapping<TabsRoot.OwnerState> = {
   direction: () => null,
   tabActivationDirection: (dir) => ({
     'data-activation-direction': dir,
diff --git a/packages/mui-base/src/Tabs/Root/useTabsRoot.ts b/packages/mui-base/src/Tabs/Root/useTabsRoot.ts
index 36d867a4a1..8c9e49354d 100644
--- a/packages/mui-base/src/Tabs/Root/useTabsRoot.ts
+++ b/packages/mui-base/src/Tabs/Root/useTabsRoot.ts
@@ -1,11 +1,7 @@
 'use client';
 import * as React from 'react';
-import type {
-  TabActivationDirection,
-  UseTabsParameters,
-  UseTabsReturnValue,
-} from './TabsRoot.types';
-import type { TabPanelMetadata } from './TabsProvider';
+import type { TabActivationDirection } from './TabsRoot';
+import type { TabsProviderValue, TabPanelMetadata } from './TabsProvider';
 import { useCompoundParent } from '../../useCompound';
 import { mergeReactProps } from '../../utils/mergeReactProps';
 import { useControlled } from '../../utils/useControlled';
@@ -18,7 +14,7 @@ export interface TabMetadata {
 
 type IdLookupFunction = (id: any) => string | undefined;
 
-function useTabsRoot(parameters: UseTabsParameters): UseTabsReturnValue {
+function useTabsRoot(parameters: useTabsRoot.Parameters): useTabsRoot.ReturnValue {
   const {
     value: valueProp,
     defaultValue,
@@ -72,7 +68,7 @@ function useTabsRoot(parameters: UseTabsParameters): UseTabsReturnValue {
     tabIdLookup.current = lookupFunction;
   }, []);
 
-  const getRootProps: UseTabsReturnValue['getRootProps'] = React.useCallback(
+  const getRootProps: useTabsRoot.ReturnValue['getRootProps'] = React.useCallback(
     (otherProps = {}) =>
       mergeReactProps<'div'>(otherProps, {
         dir: direction,
@@ -97,4 +93,43 @@ function useTabsRoot(parameters: UseTabsParameters): UseTabsReturnValue {
   };
 }
 
+namespace useTabsRoot {
+  export interface Parameters {
+    /**
+     * The value of the currently selected `Tab`.
+     * If you don't want any selected `Tab`, you can set this prop to `false`.
+     */
+    value?: any | null;
+    /**
+     * The default value. Use when the component is not controlled.
+     */
+    defaultValue?: any | null;
+    /**
+     * The component orientation (layout flow direction).
+     * @default 'horizontal'
+     */
+    orientation?: 'horizontal' | 'vertical';
+    /**
+     * The direction of the text.
+     * @default 'ltr'
+     */
+    direction?: 'ltr' | 'rtl';
+    /**
+     * Callback invoked when new value is being set.
+     */
+    onValueChange?: (value: any | null, event: React.SyntheticEvent | null) => void;
+  }
+
+  export interface ReturnValue {
+    /**
+     * Returns the values to be passed to the tabs provider.
+     */
+    contextValue: TabsProviderValue;
+    getRootProps: (
+      externalProps?: React.ComponentPropsWithRef<'div'>,
+    ) => React.ComponentPropsWithRef<'div'>;
+    tabActivationDirection: TabActivationDirection;
+  }
+}
+
 export { useTabsRoot };
diff --git a/packages/mui-base/src/Tabs/Tab/Tab.test.tsx b/packages/mui-base/src/Tabs/Tab/Tab.test.tsx
index c934ac3ed0..328052085d 100644
--- a/packages/mui-base/src/Tabs/Tab/Tab.test.tsx
+++ b/packages/mui-base/src/Tabs/Tab/Tab.test.tsx
@@ -1,12 +1,8 @@
 import * as React from 'react';
 import * as Tabs from '@base_ui/react/Tabs';
-import {
-  TabsListProvider,
-  TabsListProviderValue,
-  TabsContext,
-  TabsContextValue,
-} from '@base_ui/react/Tabs';
 import { createRenderer, describeConformance } from '#test-utils';
+import { TabsListProviderValue, TabsListProvider } from '../TabsList/TabsListProvider';
+import { TabsRootContext } from '../Root/TabsRootContext';
 
 describe('<Tabs.Tab />', () => {
   const { render } = createRenderer();
@@ -26,7 +22,7 @@ describe('<Tabs.Tab />', () => {
     },
   };
 
-  const testTabsContext: TabsContextValue = {
+  const testTabsContext: TabsRootContext = {
     value: 0,
     onSelected() {},
     registerTabIdLookup() {},
@@ -40,9 +36,9 @@ describe('<Tabs.Tab />', () => {
   describeConformance(<Tabs.Tab value="1" />, () => ({
     render: (node) => {
       return render(
-        <TabsContext.Provider value={testTabsContext}>
+        <TabsRootContext.Provider value={testTabsContext}>
           <TabsListProvider value={testTabsListContext}>{node}</TabsListProvider>
-        </TabsContext.Provider>,
+        </TabsRootContext.Provider>,
       );
     },
     refInstanceof: window.HTMLButtonElement,
diff --git a/packages/mui-base/src/Tabs/Tab/Tab.tsx b/packages/mui-base/src/Tabs/Tab/Tab.tsx
index 7cef93ed05..217fef7cbb 100644
--- a/packages/mui-base/src/Tabs/Tab/Tab.tsx
+++ b/packages/mui-base/src/Tabs/Tab/Tab.tsx
@@ -1,9 +1,10 @@
 'use client';
 import * as React from 'react';
 import PropTypes from 'prop-types';
-import { TabProps, TabOwnerState } from './Tab.types';
 import { useTab } from './useTab';
 import { useComponentRenderer } from '../../utils/useComponentRenderer';
+import type { BaseUIComponentProps } from '../../utils/types';
+import { TabsOrientation } from '../Root/TabsRoot';
 
 /**
  *
@@ -16,7 +17,7 @@ import { useComponentRenderer } from '../../utils/useComponentRenderer';
  * - [Tab API](https://base-ui.netlify.app/components/react-tabs/#api-reference-Tab)
  */
 const Tab = React.forwardRef(function Tab(
-  props: TabProps,
+  props: Tab.Props,
   forwardedRef: React.ForwardedRef<Element>,
 ) {
   const { className, disabled = false, render, value, ...other } = props;
@@ -26,7 +27,7 @@ const Tab = React.forwardRef(function Tab(
     rootRef: forwardedRef,
   });
 
-  const ownerState: TabOwnerState = {
+  const ownerState: Tab.OwnerState = {
     disabled,
     selected,
     orientation,
@@ -43,6 +44,21 @@ const Tab = React.forwardRef(function Tab(
   return renderElement();
 });
 
+namespace Tab {
+  export interface Props extends BaseUIComponentProps<'button', Tab.OwnerState> {
+    /**
+     * You can provide your own value. Otherwise, it falls back to the child position index.
+     */
+    value?: any;
+  }
+
+  export interface OwnerState {
+    disabled: boolean;
+    selected: boolean;
+    orientation: TabsOrientation;
+  }
+}
+
 Tab.propTypes /* remove-proptypes */ = {
   // ┌────────────────────────────── Warning ──────────────────────────────┐
   // │ These PropTypes are generated from the TypeScript type definitions. │
diff --git a/packages/mui-base/src/Tabs/Tab/Tab.types.ts b/packages/mui-base/src/Tabs/Tab/Tab.types.ts
deleted file mode 100644
index 23a967a844..0000000000
--- a/packages/mui-base/src/Tabs/Tab/Tab.types.ts
+++ /dev/null
@@ -1,71 +0,0 @@
-import * as React from 'react';
-import { TabsOrientation } from '../Root/TabsRoot.types';
-import { BaseUIComponentProps } from '../../utils/types';
-
-export type TabOwnerState = {
-  disabled: boolean;
-  selected: boolean;
-  orientation: TabsOrientation;
-};
-
-export interface TabProps extends BaseUIComponentProps<'button', TabOwnerState> {
-  /**
-   * You can provide your own value. Otherwise, it falls back to the child position index.
-   */
-  value?: any;
-}
-
-export interface UseTabParameters {
-  /**
-   * The value of the tab.
-   * It's used to associate the tab with a tab panel(s) with the same value.
-   * If the value is not provided, it falls back to the position index.
-   */
-  value?: any;
-  /**
-   * Callback fired when the tab is clicked.
-   */
-  onClick?: React.MouseEventHandler;
-  /**
-   * If `true`, the tab will be disabled.
-   */
-  disabled?: boolean;
-  /**
-   * The id of the tab.
-   * If not provided, it will be automatically generated.
-   */
-  id?: string;
-  /**
-   * Ref to the root slot's DOM element.
-   */
-  rootRef?: React.Ref<Element>;
-}
-
-export interface UseTabReturnValue {
-  /**
-   * Resolver for the root slot's props.
-   * @param externalProps props for the root slot
-   * @returns props that should be spread on the root slot
-   */
-  getRootProps: (
-    externalProps?: React.ComponentPropsWithRef<'button'>,
-  ) => React.ComponentPropsWithRef<'button'>;
-  /**
-   * 0-based index of the tab in the list of tabs.
-   */
-  index: number;
-  orientation: TabsOrientation;
-  /**
-   * Ref to the root slot's DOM element.
-   */
-  rootRef: React.RefCallback<Element> | null;
-  /**
-   * If `true`, the tab is selected.
-   */
-  selected: boolean;
-  /**
-   * Total number of tabs in the nearest parent TabsList.
-   * This can be used to determine if the tab is the last one to style it accordingly.
-   */
-  totalTabsCount: number;
-}
diff --git a/packages/mui-base/src/Tabs/Tab/useTab.ts b/packages/mui-base/src/Tabs/Tab/useTab.ts
index f04b4d7cf5..204ba177c2 100644
--- a/packages/mui-base/src/Tabs/Tab/useTab.ts
+++ b/packages/mui-base/src/Tabs/Tab/useTab.ts
@@ -1,7 +1,6 @@
 'use client';
 import * as React from 'react';
-import { UseTabParameters, UseTabReturnValue } from './Tab.types';
-import { useTabsContext } from '../Root/TabsContext';
+import { useTabsRootContext } from '../Root/TabsRootContext';
 import { TabMetadata } from '../Root/useTabsRoot';
 import { useCompoundItem } from '../../useCompound';
 import { useListItem } from '../../useList';
@@ -9,18 +8,19 @@ import { useButton } from '../../useButton';
 import { useId } from '../../utils/useId';
 import { useForkRef } from '../../utils/useForkRef';
 import { mergeReactProps } from '../../utils/mergeReactProps';
+import { TabsOrientation } from '../Root/TabsRoot';
 
 function tabValueGenerator(otherTabValues: Set<any>) {
   return otherTabValues.size;
 }
 
-function useTab(parameters: UseTabParameters): UseTabReturnValue {
+function useTab(parameters: useTab.Parameters): useTab.ReturnValue {
   const { value: valueParam, rootRef: externalRef, disabled = false, id: idParam } = parameters;
 
   const tabRef = React.useRef<HTMLElement>(null);
   const id = useId(idParam);
 
-  const { value: selectedValue, getTabPanelId, orientation } = useTabsContext();
+  const { value: selectedValue, getTabPanelId, orientation } = useTabsRootContext();
 
   const tabMetadata = React.useMemo(() => ({ disabled, ref: tabRef, id }), [disabled, tabRef, id]);
 
@@ -76,4 +76,61 @@ function useTab(parameters: UseTabParameters): UseTabReturnValue {
   };
 }
 
+namespace useTab {
+  export interface Parameters {
+    /**
+     * The value of the tab.
+     * It's used to associate the tab with a tab panel(s) with the same value.
+     * If the value is not provided, it falls back to the position index.
+     */
+    value?: any;
+    /**
+     * Callback fired when the tab is clicked.
+     */
+    onClick?: React.MouseEventHandler;
+    /**
+     * If `true`, the tab will be disabled.
+     */
+    disabled?: boolean;
+    /**
+     * The id of the tab.
+     * If not provided, it will be automatically generated.
+     */
+    id?: string;
+    /**
+     * Ref to the root slot's DOM element.
+     */
+    rootRef?: React.Ref<Element>;
+  }
+
+  export interface ReturnValue {
+    /**
+     * Resolver for the root slot's props.
+     * @param externalProps props for the root slot
+     * @returns props that should be spread on the root slot
+     */
+    getRootProps: (
+      externalProps?: React.ComponentPropsWithRef<'button'>,
+    ) => React.ComponentPropsWithRef<'button'>;
+    /**
+     * 0-based index of the tab in the list of tabs.
+     */
+    index: number;
+    orientation: TabsOrientation;
+    /**
+     * Ref to the root slot's DOM element.
+     */
+    rootRef: React.RefCallback<Element> | null;
+    /**
+     * If `true`, the tab is selected.
+     */
+    selected: boolean;
+    /**
+     * Total number of tabs in the nearest parent TabsList.
+     * This can be used to determine if the tab is the last one to style it accordingly.
+     */
+    totalTabsCount: number;
+  }
+}
+
 export { useTab };
diff --git a/packages/mui-base/src/Tabs/TabIndicator/TabIndicator.tsx b/packages/mui-base/src/Tabs/TabIndicator/TabIndicator.tsx
index 1ad3466f81..49d2594124 100644
--- a/packages/mui-base/src/Tabs/TabIndicator/TabIndicator.tsx
+++ b/packages/mui-base/src/Tabs/TabIndicator/TabIndicator.tsx
@@ -1,12 +1,13 @@
 'use client';
 import * as React from 'react';
 import PropTypes from 'prop-types';
-import { useTabIndicator } from './useTabIndicator';
-import { TabIndicatorOwnerState, TabIndicatorProps } from './TabIndicator.types';
+import { ActiveTabPosition, useTabIndicator } from './useTabIndicator';
 import { script as prehydrationScript } from './prehydrationScript.min';
-import { useTabsContext } from '../Root/TabsContext';
+import type { TabsDirection, TabsOrientation, TabsRoot } from '../Root/TabsRoot';
+import { useTabsRootContext } from '../Root/TabsRootContext';
 import { tabsStyleHookMapping } from '../Root/styleHooks';
 import { useComponentRenderer } from '../../utils/useComponentRenderer';
+import type { BaseUIComponentProps } from '../../utils/types';
 
 const noop = () => null;
 
@@ -20,13 +21,13 @@ const noop = () => null;
  *
  * - [TabIndicator API](https://base-ui.netlify.app/components/react-tabs/#api-reference-TabIndicator)
  */
-const TabIndicator = React.forwardRef<HTMLSpanElement, TabIndicatorProps>(
+const TabIndicator = React.forwardRef<HTMLSpanElement, TabIndicator.Props>(
   function TabIndicator(props, forwardedRef) {
     const { className, render, renderBeforeHydration = false, ...other } = props;
 
     const [instanceId] = React.useState(() => Math.random().toString(36).slice(2));
     const [isMounted, setIsMounted] = React.useState(false);
-    const { value: activeTabValue } = useTabsContext();
+    const { value: activeTabValue } = useTabsRootContext();
 
     React.useEffect(() => {
       setIsMounted(true);
@@ -40,7 +41,7 @@ const TabIndicator = React.forwardRef<HTMLSpanElement, TabIndicatorProps>(
       tabActivationDirection,
     } = useTabIndicator();
 
-    const ownerState: TabIndicatorOwnerState = {
+    const ownerState: TabIndicator.OwnerState = {
       selectedTabPosition,
       orientation,
       direction,
@@ -83,6 +84,24 @@ const TabIndicator = React.forwardRef<HTMLSpanElement, TabIndicatorProps>(
   },
 );
 
+namespace TabIndicator {
+  export interface OwnerState extends TabsRoot.OwnerState {
+    selectedTabPosition: ActiveTabPosition | null;
+    orientation: TabsOrientation;
+    direction: TabsDirection;
+  }
+
+  export interface Props extends BaseUIComponentProps<'span', TabIndicator.OwnerState> {
+    /**
+     * If `true`, the indicator will include code to render itself before React hydrates.
+     * This will minimize the time the indicator is not visible after the SSR-generated content is downloaded.
+     *
+     * @default false
+     */
+    renderBeforeHydration?: boolean;
+  }
+}
+
 TabIndicator.propTypes /* remove-proptypes */ = {
   // ┌────────────────────────────── Warning ──────────────────────────────┐
   // │ These PropTypes are generated from the TypeScript type definitions. │
diff --git a/packages/mui-base/src/Tabs/TabIndicator/TabIndicator.types.ts b/packages/mui-base/src/Tabs/TabIndicator/TabIndicator.types.ts
deleted file mode 100644
index 556c5af33b..0000000000
--- a/packages/mui-base/src/Tabs/TabIndicator/TabIndicator.types.ts
+++ /dev/null
@@ -1,40 +0,0 @@
-import type { BaseUIComponentProps } from '../../utils/types';
-import type {
-  TabActivationDirection,
-  TabsDirection,
-  TabsOrientation,
-  TabsRootOwnerState,
-} from '../Root/TabsRoot.types';
-
-export type TabIndicatorOwnerState = TabsRootOwnerState & {
-  selectedTabPosition: ActiveTabPosition | null;
-  orientation: TabsOrientation;
-  direction: TabsDirection;
-};
-
-export interface TabIndicatorProps extends BaseUIComponentProps<'span', TabIndicatorOwnerState> {
-  /**
-   * If `true`, the indicator will include code to render itself before React hydrates.
-   * This will minimize the time the indicator is not visible after the SSR-generated content is downloaded.
-   *
-   * @default false
-   */
-  renderBeforeHydration?: boolean;
-}
-
-export interface ActiveTabPosition {
-  left: number;
-  right: number;
-  top: number;
-  bottom: number;
-}
-
-export type UseTabIndicatorReturnValue = {
-  getRootProps: (
-    otherProps?: React.ComponentPropsWithRef<'span'>,
-  ) => React.ComponentPropsWithRef<'span'>;
-  activeTabPosition: ActiveTabPosition | null;
-  direction: TabsDirection;
-  orientation: TabsOrientation;
-  tabActivationDirection: TabActivationDirection;
-};
diff --git a/packages/mui-base/src/Tabs/TabIndicator/useTabIndicator.ts b/packages/mui-base/src/Tabs/TabIndicator/useTabIndicator.ts
index 6991388e36..8571028952 100644
--- a/packages/mui-base/src/Tabs/TabIndicator/useTabIndicator.ts
+++ b/packages/mui-base/src/Tabs/TabIndicator/useTabIndicator.ts
@@ -1,18 +1,18 @@
 'use client';
 import * as React from 'react';
-import { UseTabIndicatorReturnValue } from './TabIndicator.types';
 import { useTabsListContext } from '../TabsList/TabsListContext';
-import { useTabsContext } from '../Root/TabsContext';
+import { useTabsRootContext } from '../Root/TabsRootContext';
 import { mergeReactProps } from '../../utils/mergeReactProps';
 import { useForcedRerendering } from '../../utils/useForcedRerendering';
+import type { TabsDirection, TabsOrientation, TabActivationDirection } from '../Root/TabsRoot';
 
 function round(value: number) {
   return Math.round(value * 100) * 0.01;
 }
 
-export function useTabIndicator(): UseTabIndicatorReturnValue {
+export function useTabIndicator(): useTabIndicator.ReturnValue {
   const { tabsListRef, getTabElement } = useTabsListContext();
-  const { orientation, direction, value, tabActivationDirection } = useTabsContext();
+  const { orientation, direction, value, tabActivationDirection } = useTabsRootContext();
 
   const rerender = useForcedRerendering();
   React.useEffect(() => {
@@ -114,3 +114,22 @@ export function useTabIndicator(): UseTabIndicatorReturnValue {
     tabActivationDirection,
   };
 }
+
+export interface ActiveTabPosition {
+  left: number;
+  right: number;
+  top: number;
+  bottom: number;
+}
+
+export namespace useTabIndicator {
+  export interface ReturnValue {
+    getRootProps: (
+      otherProps?: React.ComponentPropsWithRef<'span'>,
+    ) => React.ComponentPropsWithRef<'span'>;
+    activeTabPosition: ActiveTabPosition | null;
+    direction: TabsDirection;
+    orientation: TabsOrientation;
+    tabActivationDirection: TabActivationDirection;
+  }
+}
diff --git a/packages/mui-base/src/Tabs/TabPanel/TabPanel.test.tsx b/packages/mui-base/src/Tabs/TabPanel/TabPanel.test.tsx
index bda8b77f36..b17e0b994b 100644
--- a/packages/mui-base/src/Tabs/TabPanel/TabPanel.test.tsx
+++ b/packages/mui-base/src/Tabs/TabPanel/TabPanel.test.tsx
@@ -1,7 +1,7 @@
 import * as React from 'react';
 import * as Tabs from '@base_ui/react/Tabs';
-import { TabsProvider, TabsProviderValue } from '@base_ui/react/Tabs';
 import { createRenderer, describeConformance } from '#test-utils';
+import { TabsProvider, TabsProviderValue } from '../Root/TabsProvider';
 
 describe('<Tabs.Panel />', () => {
   const { render } = createRenderer();
diff --git a/packages/mui-base/src/Tabs/TabPanel/TabPanel.tsx b/packages/mui-base/src/Tabs/TabPanel/TabPanel.tsx
index 4d26218618..d01692b243 100644
--- a/packages/mui-base/src/Tabs/TabPanel/TabPanel.tsx
+++ b/packages/mui-base/src/Tabs/TabPanel/TabPanel.tsx
@@ -2,9 +2,10 @@
 import * as React from 'react';
 import PropTypes from 'prop-types';
 import { useTabPanel } from './useTabPanel';
-import { TabPanelOwnerState, TabPanelProps } from './TabPanel.types';
 import { tabsStyleHookMapping } from '../Root/styleHooks';
 import { useComponentRenderer } from '../../utils/useComponentRenderer';
+import { TabsRoot } from '../Root/TabsRoot';
+import type { BaseUIComponentProps } from '../../utils/types';
 
 /**
  *
@@ -17,7 +18,7 @@ import { useComponentRenderer } from '../../utils/useComponentRenderer';
  * - [TabPanel API](https://base-ui.netlify.app/components/react-tabs/#api-reference-TabPanel)
  */
 const TabPanel = React.forwardRef(function TabPanel(
-  props: TabPanelProps,
+  props: TabPanel.Props,
   forwardedRef: React.ForwardedRef<HTMLDivElement>,
 ) {
   const { children, className, value, render, keepMounted = false, ...other } = props;
@@ -27,7 +28,7 @@ const TabPanel = React.forwardRef(function TabPanel(
     rootRef: forwardedRef,
   });
 
-  const ownerState: TabPanelOwnerState = {
+  const ownerState: TabPanel.OwnerState = {
     hidden,
     orientation,
     direction,
@@ -46,6 +47,26 @@ const TabPanel = React.forwardRef(function TabPanel(
   return renderElement();
 });
 
+namespace TabPanel {
+  export interface OwnerState extends TabsRoot.OwnerState {
+    hidden: boolean;
+  }
+
+  export interface Props extends BaseUIComponentProps<'div', OwnerState> {
+    /**
+     * The value of the TabPanel. It will be shown when the Tab with the corresponding value is selected.
+     * If not provided, it will fall back to the index of the panel.
+     * It is recommended to explicitly provide it, as it's required for the tab panel to be rendered on the server.
+     */
+    value?: any;
+    /**
+     * If `true`, keeps the contents of the hidden TabPanel in the DOM.
+     * @default false
+     */
+    keepMounted?: boolean;
+  }
+}
+
 TabPanel.propTypes /* remove-proptypes */ = {
   // ┌────────────────────────────── Warning ──────────────────────────────┐
   // │ These PropTypes are generated from the TypeScript type definitions. │
diff --git a/packages/mui-base/src/Tabs/TabPanel/TabPanel.types.ts b/packages/mui-base/src/Tabs/TabPanel/TabPanel.types.ts
deleted file mode 100644
index edeeb851ed..0000000000
--- a/packages/mui-base/src/Tabs/TabPanel/TabPanel.types.ts
+++ /dev/null
@@ -1,59 +0,0 @@
-import type {
-  TabActivationDirection,
-  TabsDirection,
-  TabsOrientation,
-  TabsRootOwnerState,
-} from '../Root/TabsRoot.types';
-import type { BaseUIComponentProps } from '../../utils/types';
-
-export type TabPanelOwnerState = TabsRootOwnerState & {
-  hidden: boolean;
-};
-
-export interface TabPanelProps extends BaseUIComponentProps<'div', TabPanelOwnerState> {
-  /**
-   * The value of the TabPanel. It will be shown when the Tab with the corresponding value is selected.
-   * If not provided, it will fall back to the index of the panel.
-   * It is recommended to explicitly provide it, as it's required for the tab panel to be rendered on the server.
-   */
-  value?: any;
-  /**
-   * If `true`, keeps the contents of the hidden TabPanel in the DOM.
-   * @default false
-   */
-  keepMounted?: boolean;
-}
-
-export interface UseTabPanelParameters {
-  /**
-   * The id of the TabPanel.
-   */
-  id?: string;
-  /**
-   * The ref of the TabPanel.
-   */
-  rootRef?: React.Ref<HTMLElement>;
-  /**
-   * The value of the TabPanel. It will be shown when the Tab with the corresponding value is selected.
-   */
-  value?: any;
-}
-
-export interface UseTabPanelReturnValue {
-  /**
-   * If `true`, it indicates that the tab panel will be hidden.
-   */
-  hidden: boolean;
-  /**
-   * Resolver for the root slot's props.
-   * @param externalProps additional props for the root slot
-   * @returns props that should be spread on the root slot
-   */
-  getRootProps: (
-    externalProps?: React.ComponentPropsWithRef<'div'>,
-  ) => React.ComponentPropsWithRef<'div'>;
-  rootRef: React.RefCallback<HTMLElement> | null;
-  orientation: TabsOrientation;
-  direction: TabsDirection;
-  tabActivationDirection: TabActivationDirection;
-}
diff --git a/packages/mui-base/src/Tabs/TabPanel/useTabPanel.test.tsx b/packages/mui-base/src/Tabs/TabPanel/useTabPanel.test.tsx
index 48fda35afe..3e9b644a92 100644
--- a/packages/mui-base/src/Tabs/TabPanel/useTabPanel.test.tsx
+++ b/packages/mui-base/src/Tabs/TabPanel/useTabPanel.test.tsx
@@ -3,6 +3,7 @@ import { expect } from 'chai';
 import { spy } from 'sinon';
 import { createRenderer, screen, fireEvent } from '@mui/internal-test-utils';
 import * as Tabs from '@base_ui/react/Tabs';
+import { useTabPanel } from './useTabPanel';
 
 describe('useTabPanel', () => {
   const { render } = createRenderer();
@@ -11,7 +12,7 @@ describe('useTabPanel', () => {
     it('returns props for root slot', () => {
       const rootRef = React.createRef<HTMLDivElement>();
       function TestTabPanel() {
-        const { getRootProps } = Tabs.useTabPanel({ rootRef, id: 'test-tabpanel', value: 0 });
+        const { getRootProps } = useTabPanel({ rootRef, id: 'test-tabpanel', value: 0 });
         return <div {...getRootProps()} />;
       }
 
@@ -34,7 +35,7 @@ describe('useTabPanel', () => {
       const rootRef = React.createRef<HTMLElement>();
 
       function TestTabPanel() {
-        const { getRootProps } = Tabs.useTabPanel({ rootRef, value: 0 });
+        const { getRootProps } = useTabPanel({ rootRef, value: 0 });
         return (
           <div
             {...getRootProps({
diff --git a/packages/mui-base/src/Tabs/TabPanel/useTabPanel.ts b/packages/mui-base/src/Tabs/TabPanel/useTabPanel.ts
index 4c6ca3790b..7ffb05ac4e 100644
--- a/packages/mui-base/src/Tabs/TabPanel/useTabPanel.ts
+++ b/packages/mui-base/src/Tabs/TabPanel/useTabPanel.ts
@@ -1,17 +1,17 @@
 'use client';
 import * as React from 'react';
-import { UseTabPanelParameters, UseTabPanelReturnValue } from './TabPanel.types';
-import { useTabsContext } from '../Root/TabsContext';
+import { useTabsRootContext } from '../Root/TabsRootContext';
 import { useCompoundItem } from '../../useCompound';
 import { useId } from '../../utils/useId';
 import { useForkRef } from '../../utils/useForkRef';
 import { mergeReactProps } from '../../utils/mergeReactProps';
+import { TabActivationDirection, TabsDirection, TabsOrientation } from '../Root/TabsRoot';
 
 function tabPanelValueGenerator(otherTabPanelValues: Set<any>) {
   return otherTabPanelValues.size;
 }
 
-function useTabPanel(parameters: UseTabPanelParameters): UseTabPanelReturnValue {
+function useTabPanel(parameters: useTabPanel.Parameters): useTabPanel.ReturnValue {
   const { value: valueParam, id: idParam, rootRef: externalRef } = parameters;
   const {
     value: selectedTabValue,
@@ -19,7 +19,7 @@ function useTabPanel(parameters: UseTabPanelParameters): UseTabPanelReturnValue
     orientation,
     direction,
     tabActivationDirection,
-  } = useTabsContext();
+  } = useTabsRootContext();
 
   const id = useId(idParam);
   const ref = React.useRef<HTMLElement>(null);
@@ -58,4 +58,40 @@ function useTabPanel(parameters: UseTabPanelParameters): UseTabPanelReturnValue
   };
 }
 
+namespace useTabPanel {
+  export interface Parameters {
+    /**
+     * The id of the TabPanel.
+     */
+    id?: string;
+    /**
+     * The ref of the TabPanel.
+     */
+    rootRef?: React.Ref<HTMLElement>;
+    /**
+     * The value of the TabPanel. It will be shown when the Tab with the corresponding value is selected.
+     */
+    value?: any;
+  }
+
+  export interface ReturnValue {
+    /**
+     * If `true`, it indicates that the tab panel will be hidden.
+     */
+    hidden: boolean;
+    /**
+     * Resolver for the root slot's props.
+     * @param externalProps additional props for the root slot
+     * @returns props that should be spread on the root slot
+     */
+    getRootProps: (
+      externalProps?: React.ComponentPropsWithRef<'div'>,
+    ) => React.ComponentPropsWithRef<'div'>;
+    rootRef: React.RefCallback<HTMLElement> | null;
+    orientation: TabsOrientation;
+    direction: TabsDirection;
+    tabActivationDirection: TabActivationDirection;
+  }
+}
+
 export { useTabPanel };
diff --git a/packages/mui-base/src/Tabs/TabsList/TabsList.test.tsx b/packages/mui-base/src/Tabs/TabsList/TabsList.test.tsx
index 1979841892..3c38e7ff34 100644
--- a/packages/mui-base/src/Tabs/TabsList/TabsList.test.tsx
+++ b/packages/mui-base/src/Tabs/TabsList/TabsList.test.tsx
@@ -2,8 +2,8 @@ import * as React from 'react';
 import { expect } from 'chai';
 import { act } from '@mui/internal-test-utils';
 import * as Tabs from '@base_ui/react/Tabs';
-import { TabsContext } from '@base_ui/react/Tabs';
 import { createRenderer, describeConformance } from '#test-utils';
+import { TabsRootContext } from '../Root/TabsRootContext';
 
 describe('<Tabs.List />', () => {
   const { render } = createRenderer();
@@ -11,7 +11,7 @@ describe('<Tabs.List />', () => {
   describeConformance(<Tabs.List />, () => ({
     render: (node) => {
       return render(
-        <TabsContext.Provider
+        <TabsRootContext.Provider
           value={{
             value: '1',
             onSelected: () => {},
@@ -24,7 +24,7 @@ describe('<Tabs.List />', () => {
           }}
         >
           {node}
-        </TabsContext.Provider>,
+        </TabsRootContext.Provider>,
       );
     },
     refInstanceof: window.HTMLDivElement,
diff --git a/packages/mui-base/src/Tabs/TabsList/TabsList.tsx b/packages/mui-base/src/Tabs/TabsList/TabsList.tsx
index 7cc96d2771..140f0a8d9d 100644
--- a/packages/mui-base/src/Tabs/TabsList/TabsList.tsx
+++ b/packages/mui-base/src/Tabs/TabsList/TabsList.tsx
@@ -1,11 +1,12 @@
 'use client';
 import * as React from 'react';
 import PropTypes from 'prop-types';
-import { TabsListOwnerState, TabsListProps } from './TabsList.types';
 import { useTabsList } from './useTabsList';
 import { TabsListProvider } from './TabsListProvider';
 import { tabsStyleHookMapping } from '../Root/styleHooks';
 import { useComponentRenderer } from '../../utils/useComponentRenderer';
+import { TabsRoot } from '../Root/TabsRoot';
+import { BaseUIComponentProps } from '../../utils/types';
 
 /**
  *
@@ -18,7 +19,7 @@ import { useComponentRenderer } from '../../utils/useComponentRenderer';
  * - [TabsList API](https://base-ui.netlify.app/components/react-tabs/#api-reference-TabsList)
  */
 const TabsList = React.forwardRef(function TabsList(
-  props: TabsListProps,
+  props: TabsList.Props,
   forwardedRef: React.ForwardedRef<HTMLDivElement>,
 ) {
   const { activateOnFocus = true, className, loop = true, render, ...other } = props;
@@ -30,7 +31,7 @@ const TabsList = React.forwardRef(function TabsList(
       activateOnFocus,
     });
 
-  const ownerState: TabsListOwnerState = React.useMemo(
+  const ownerState: TabsList.OwnerState = React.useMemo(
     () => ({
       direction,
       orientation,
@@ -51,6 +52,26 @@ const TabsList = React.forwardRef(function TabsList(
   return <TabsListProvider value={contextValue}>{renderElement()}</TabsListProvider>;
 });
 
+namespace TabsList {
+  export type OwnerState = TabsRoot.OwnerState;
+
+  export interface Props extends BaseUIComponentProps<'div', TabsList.OwnerState> {
+    /**
+     * If `true`, the tab will be activated whenever it is focused.
+     * Otherwise, it has to be activated by clicking or pressing the Enter or Space key.
+     *
+     * @default true
+     */
+    activateOnFocus?: boolean;
+    /**
+     * If `true`, using keyboard navigation will wrap focus to the other end of the list once the end is reached.
+     *
+     * @default true
+     */
+    loop?: boolean;
+  }
+}
+
 TabsList.propTypes /* remove-proptypes */ = {
   // ┌────────────────────────────── Warning ──────────────────────────────┐
   // │ These PropTypes are generated from the TypeScript type definitions. │
diff --git a/packages/mui-base/src/Tabs/TabsList/TabsList.types.ts b/packages/mui-base/src/Tabs/TabsList/TabsList.types.ts
deleted file mode 100644
index 22d8c8bc3f..0000000000
--- a/packages/mui-base/src/Tabs/TabsList/TabsList.types.ts
+++ /dev/null
@@ -1,90 +0,0 @@
-import { TabsListProviderValue } from './TabsListProvider';
-import {
-  TabActivationDirection,
-  TabsDirection,
-  TabsOrientation,
-  TabsRootOwnerState,
-} from '../Root/TabsRoot.types';
-import { ListAction } from '../../useList';
-import { BaseUIComponentProps } from '../../utils/types';
-
-export type TabsListOwnerState = TabsRootOwnerState;
-
-export interface TabsListProps extends BaseUIComponentProps<'div', TabsListOwnerState> {
-  /**
-   * If `true`, the tab will be activated whenever it is focused.
-   * Otherwise, it has to be activated by clicking or pressing the Enter or Space key.
-   *
-   * @default true
-   */
-  activateOnFocus?: boolean;
-  /**
-   * If `true`, using keyboard navigation will wrap focus to the other end of the list once the end is reached.
-   *
-   * @default true
-   */
-  loop?: boolean;
-}
-
-export interface UseTabsListParameters {
-  /**
-   * If `true`, the tab will be activated whenever it is focused.
-   * Otherwise, it has to be activated by clicking or pressing the Enter or Space key.
-   */
-  activateOnFocus: boolean;
-  /**
-   * If `true`, using keyboard navigation will wrap focus to the other end of the list once the end is reached.
-   */
-  loop: boolean;
-  /**
-   * Ref to the root element.
-   */
-  rootRef: React.Ref<Element>;
-}
-
-export interface UseTabsListReturnValue {
-  /**
-   * The value to be passed to the TabListProvider above all the tabs.
-   */
-  contextValue: TabsListProviderValue;
-  /**
-   * Action dispatcher for the tabs list component.
-   * Allows to programmatically control the tabs list.
-   */
-  dispatch: (action: ListAction<any>) => void;
-  /**
-   * Resolver for the root slot's props.
-   * @param externalProps props for the root slot
-   * @returns props that should be spread on the root slot
-   */
-  getRootProps: (
-    externalProps?: React.ComponentPropsWithRef<'div'>,
-  ) => React.ComponentPropsWithRef<'div'>;
-  /**
-   * The value of the currently highlighted tab.
-   */
-  highlightedValue: any | null;
-  /**
-   * If `true`, it will indicate that the text's direction in right-to-left.
-   */
-  direction: TabsDirection;
-  /**
-   * The component orientation (layout flow direction).
-   */
-  orientation: TabsOrientation;
-  rootRef: React.RefCallback<Element> | null;
-  /**
-   * The value of the currently selected tab.
-   */
-  selectedValue: any | null;
-  tabActivationDirection: TabActivationDirection;
-}
-
-export const TabsListActionTypes = {
-  valueChange: 'valueChange',
-} as const;
-
-export interface ValueChangeAction {
-  type: typeof TabsListActionTypes.valueChange;
-  value: any | null;
-}
diff --git a/packages/mui-base/src/Tabs/TabsList/TabsListContext.ts b/packages/mui-base/src/Tabs/TabsList/TabsListContext.ts
index c8d8a6ddf1..9b2833529d 100644
--- a/packages/mui-base/src/Tabs/TabsList/TabsListContext.ts
+++ b/packages/mui-base/src/Tabs/TabsList/TabsListContext.ts
@@ -1,13 +1,13 @@
 'use client';
 import * as React from 'react';
 
-export type TabsListContextValue = {
+export interface TabsListContext {
   activateOnFocus: boolean;
   getTabElement: (value: any) => HTMLElement | null;
   tabsListRef: React.RefObject<HTMLElement | null>;
-};
+}
 
-export const TabsListContext = React.createContext<TabsListContextValue | undefined>(undefined);
+export const TabsListContext = React.createContext<TabsListContext | undefined>(undefined);
 
 export function useTabsListContext() {
   const context = React.useContext(TabsListContext);
diff --git a/packages/mui-base/src/Tabs/TabsList/TabsListProvider.tsx b/packages/mui-base/src/Tabs/TabsList/TabsListProvider.tsx
index a7e042824f..1e2a319e92 100644
--- a/packages/mui-base/src/Tabs/TabsList/TabsListProvider.tsx
+++ b/packages/mui-base/src/Tabs/TabsList/TabsListProvider.tsx
@@ -1,7 +1,7 @@
 'use client';
 import * as React from 'react';
 import PropTypes from 'prop-types';
-import { TabsListContext, TabsListContextValue } from './TabsListContext';
+import { TabsListContext } from './TabsListContext';
 import { TabMetadata } from '../Root/useTabsRoot';
 import { ListContext, ListContextValue } from '../../useList/ListContext';
 import { CompoundComponentContext, CompoundComponentContextValue } from '../../useCompound';
@@ -9,7 +9,7 @@ import { refType } from '../../utils/proptypes';
 
 export type TabsListProviderValue = CompoundComponentContextValue<any, TabMetadata> &
   ListContextValue<any> &
-  TabsListContextValue;
+  TabsListContext;
 
 export interface TabsListProviderProps {
   value: TabsListProviderValue;
@@ -53,7 +53,7 @@ function TabsListProvider(props: TabsListProviderProps) {
       [registerItem, getItemIndex, totalSubitemCount],
     );
 
-  const tabsListContextValue: TabsListContextValue = React.useMemo(
+  const tabsListContextValue: TabsListContext = React.useMemo(
     () => ({ activateOnFocus, getTabElement, tabsListRef }),
     [activateOnFocus, getTabElement, tabsListRef],
   );
diff --git a/packages/mui-base/src/Tabs/TabsList/tabsListReducer.ts b/packages/mui-base/src/Tabs/TabsList/tabsListReducer.ts
index e337803e9c..903bed29a6 100644
--- a/packages/mui-base/src/Tabs/TabsList/tabsListReducer.ts
+++ b/packages/mui-base/src/Tabs/TabsList/tabsListReducer.ts
@@ -1,4 +1,3 @@
-import { TabsListActionTypes, ValueChangeAction } from './TabsList.types';
 import {
   ListState,
   ListAction,
@@ -13,6 +12,15 @@ export type TabsListActionContext = ListActionContext<any> & {
   activateOnFocus: boolean;
 };
 
+export const TabsListActionTypes = {
+  valueChange: 'valueChange',
+} as const;
+
+export interface ValueChangeAction {
+  type: typeof TabsListActionTypes.valueChange;
+  value: any | null;
+}
+
 export function tabsListReducer(
   state: ListState<any>,
   action: ActionWithContext<ListAction<any> | ValueChangeAction, TabsListActionContext>,
diff --git a/packages/mui-base/src/Tabs/TabsList/useTabsList.ts b/packages/mui-base/src/Tabs/TabsList/useTabsList.ts
index 07fe4272f6..5ecbbbb81f 100644
--- a/packages/mui-base/src/Tabs/TabsList/useTabsList.ts
+++ b/packages/mui-base/src/Tabs/TabsList/useTabsList.ts
@@ -1,22 +1,18 @@
 'use client';
 import * as React from 'react';
-import {
-  TabsListActionTypes,
-  type UseTabsListParameters,
-  type UseTabsListReturnValue,
-  type ValueChangeAction,
-} from './TabsList.types';
-import { tabsListReducer } from './tabsListReducer';
-import { useTabsContext } from '../Root/TabsContext';
+import { TabsListActionTypes, tabsListReducer, ValueChangeAction } from './tabsListReducer';
+import { useTabsRootContext } from '../Root/TabsRootContext';
 import { type TabMetadata } from '../Root/useTabsRoot';
-import { type TabsOrientation, type TabActivationDirection } from '../Root/TabsRoot.types';
+import { type TabsOrientation, type TabActivationDirection } from '../Root/TabsRoot';
 import { useCompoundParent } from '../../useCompound';
-import { useList, ListState, UseListParameters } from '../../useList';
+import { useList, ListState, UseListParameters, ListAction } from '../../useList';
 import { useForkRef } from '../../utils/useForkRef';
 import { mergeReactProps } from '../../utils/mergeReactProps';
 import { useEnhancedEffect } from '../../utils/useEnhancedEffect';
+import { TabsDirection } from '../Root/TabsRoot';
+import { TabsListProviderValue } from './TabsListProvider';
 
-function useTabsList(parameters: UseTabsListParameters): UseTabsListReturnValue {
+function useTabsList(parameters: useTabsList.Parameters): useTabsList.ReturnValue {
   const { rootRef: externalRef, loop, activateOnFocus } = parameters;
 
   const {
@@ -26,7 +22,7 @@ function useTabsList(parameters: UseTabsListParameters): UseTabsListReturnValue
     value,
     registerTabIdLookup,
     tabActivationDirection,
-  } = useTabsContext();
+  } = useTabsRootContext();
 
   const { subitems, contextValue: compoundComponentContextValue } = useCompoundParent<
     any,
@@ -263,4 +259,60 @@ function useActivationDirectionDetector(
   );
 }
 
+namespace useTabsList {
+  export interface Parameters {
+    /**
+     * If `true`, the tab will be activated whenever it is focused.
+     * Otherwise, it has to be activated by clicking or pressing the Enter or Space key.
+     */
+    activateOnFocus: boolean;
+    /**
+     * If `true`, using keyboard navigation will wrap focus to the other end of the list once the end is reached.
+     */
+    loop: boolean;
+    /**
+     * Ref to the root element.
+     */
+    rootRef: React.Ref<Element>;
+  }
+
+  export interface ReturnValue {
+    /**
+     * The value to be passed to the TabListProvider above all the tabs.
+     */
+    contextValue: TabsListProviderValue;
+    /**
+     * Action dispatcher for the tabs list component.
+     * Allows to programmatically control the tabs list.
+     */
+    dispatch: (action: ListAction<any>) => void;
+    /**
+     * Resolver for the root slot's props.
+     * @param externalProps props for the root slot
+     * @returns props that should be spread on the root slot
+     */
+    getRootProps: (
+      externalProps?: React.ComponentPropsWithRef<'div'>,
+    ) => React.ComponentPropsWithRef<'div'>;
+    /**
+     * The value of the currently highlighted tab.
+     */
+    highlightedValue: any | null;
+    /**
+     * If `true`, it will indicate that the text's direction in right-to-left.
+     */
+    direction: TabsDirection;
+    /**
+     * The component orientation (layout flow direction).
+     */
+    orientation: TabsOrientation;
+    rootRef: React.RefCallback<Element> | null;
+    /**
+     * The value of the currently selected tab.
+     */
+    selectedValue: any | null;
+    tabActivationDirection: TabActivationDirection;
+  }
+}
+
 export { useTabsList };
diff --git a/packages/mui-base/src/Tabs/index.barrel.ts b/packages/mui-base/src/Tabs/index.barrel.ts
index 04656786ba..d8c499e9e6 100644
--- a/packages/mui-base/src/Tabs/index.barrel.ts
+++ b/packages/mui-base/src/Tabs/index.barrel.ts
@@ -1,43 +1,5 @@
 export { TabsRoot } from './Root/TabsRoot';
-export type {
-  TabsRootOwnerState,
-  TabsRootProps,
-  TabsDirection,
-  TabsOrientation,
-  UseTabsParameters,
-  UseTabsReturnValue,
-} from './Root/TabsRoot.types';
-export { useTabsRoot } from './Root/useTabsRoot';
-export { TabsContext, type TabsContextValue, useTabsContext } from './Root/TabsContext';
-export * from './Root/TabsProvider';
-
 export { Tab } from './Tab/Tab';
-export type { TabOwnerState, TabProps, UseTabParameters, UseTabReturnValue } from './Tab/Tab.types';
-export { useTab } from './Tab/useTab';
-
 export { TabIndicator } from './TabIndicator/TabIndicator';
-export type {
-  TabIndicatorOwnerState,
-  TabIndicatorProps,
-  UseTabIndicatorReturnValue,
-} from './TabIndicator/TabIndicator.types';
-export { useTabIndicator } from './TabIndicator/useTabIndicator';
-
 export { TabPanel } from './TabPanel/TabPanel';
-export type {
-  TabPanelOwnerState,
-  TabPanelProps,
-  UseTabPanelParameters,
-  UseTabPanelReturnValue,
-} from './TabPanel/TabPanel.types';
-export { useTabPanel } from './TabPanel/useTabPanel';
-
 export { TabsList } from './TabsList/TabsList';
-export type {
-  TabsListOwnerState,
-  TabsListProps,
-  UseTabsListParameters,
-  UseTabsListReturnValue,
-} from './TabsList/TabsList.types';
-export * from './TabsList/TabsListProvider';
-export { useTabsList } from './TabsList/useTabsList';
diff --git a/packages/mui-base/src/Tabs/index.ts b/packages/mui-base/src/Tabs/index.ts
index a204765d0d..acb9d122d3 100644
--- a/packages/mui-base/src/Tabs/index.ts
+++ b/packages/mui-base/src/Tabs/index.ts
@@ -1,43 +1,5 @@
 export { TabsRoot as Root } from './Root/TabsRoot';
-export type {
-  TabsRootOwnerState as RootOwnerState,
-  TabsRootProps as RootProps,
-  TabsDirection as Direction,
-  TabsOrientation as Orientation,
-  UseTabsParameters,
-  UseTabsReturnValue,
-} from './Root/TabsRoot.types';
-export { useTabsRoot } from './Root/useTabsRoot';
-export { TabsContext, type TabsContextValue, useTabsContext } from './Root/TabsContext';
-export * from './Root/TabsProvider';
-
 export { Tab } from './Tab/Tab';
-export type { TabOwnerState, TabProps, UseTabParameters, UseTabReturnValue } from './Tab/Tab.types';
-export { useTab } from './Tab/useTab';
-
 export { TabIndicator as Indicator } from './TabIndicator/TabIndicator';
-export type {
-  TabIndicatorOwnerState as IndicatorOwnerState,
-  TabIndicatorProps as IndicatorProps,
-  UseTabIndicatorReturnValue,
-} from './TabIndicator/TabIndicator.types';
-export { useTabIndicator } from './TabIndicator/useTabIndicator';
-
 export { TabPanel as Panel } from './TabPanel/TabPanel';
-export type {
-  TabPanelOwnerState as PanelOwnerState,
-  TabPanelProps as PanelProps,
-  UseTabPanelParameters,
-  UseTabPanelReturnValue,
-} from './TabPanel/TabPanel.types';
-export { useTabPanel } from './TabPanel/useTabPanel';
-
 export { TabsList as List } from './TabsList/TabsList';
-export type {
-  TabsListOwnerState as ListOwnerState,
-  TabsListProps as ListProps,
-  UseTabsListParameters,
-  UseTabsListReturnValue,
-} from './TabsList/TabsList.types';
-export * from './TabsList/TabsListProvider';
-export { useTabsList } from './TabsList/useTabsList';

From 37783b0392d57a5d6ee9133eb4703ee10a1dd57e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Dudak?= <michal@mui.com>
Date: Mon, 7 Oct 2024 11:23:07 +0200
Subject: [PATCH 4/4] [Fieldset] Move types to namespaces (#711)

---
 .../src/Fieldset/Legend/FieldsetLegend.tsx     | 14 +++++++++++---
 .../Fieldset/Legend/FieldsetLegend.types.ts    |  8 --------
 .../src/Fieldset/Legend/useFieldsetLegend.ts   | 12 +++++++-----
 .../src/Fieldset/Root/FieldsetRoot.tsx         | 18 +++++++++++++-----
 .../src/Fieldset/Root/FieldsetRoot.types.ts    |  8 --------
 .../src/Fieldset/Root/FieldsetRootContext.ts   |  4 ++--
 packages/mui-base/src/Fieldset/index.barrel.ts |  3 ---
 packages/mui-base/src/Fieldset/index.ts        |  9 ---------
 8 files changed, 33 insertions(+), 43 deletions(-)
 delete mode 100644 packages/mui-base/src/Fieldset/Legend/FieldsetLegend.types.ts
 delete mode 100644 packages/mui-base/src/Fieldset/Root/FieldsetRoot.types.ts

diff --git a/packages/mui-base/src/Fieldset/Legend/FieldsetLegend.tsx b/packages/mui-base/src/Fieldset/Legend/FieldsetLegend.tsx
index 3671ee60d1..5fbedd9654 100644
--- a/packages/mui-base/src/Fieldset/Legend/FieldsetLegend.tsx
+++ b/packages/mui-base/src/Fieldset/Legend/FieldsetLegend.tsx
@@ -1,10 +1,10 @@
 'use client';
 import * as React from 'react';
 import PropTypes from 'prop-types';
-import type { FieldsetLegendOwnerState, FieldsetLegendProps } from './FieldsetLegend.types';
 import { useComponentRenderer } from '../../utils/useComponentRenderer';
 import { useFieldsetLegend } from './useFieldsetLegend';
 import { useFieldsetRootContext } from '../Root/FieldsetRootContext';
+import type { BaseUIComponentProps } from '../../utils/types';
 
 /**
  * Renders an element that labels the fieldset.
@@ -18,7 +18,7 @@ import { useFieldsetRootContext } from '../Root/FieldsetRootContext';
  * - [FieldsetLegend API](https://base-ui.netlify.app/components/react-fieldset/#api-reference-FieldsetLegend)
  */
 const FieldsetLegend = React.forwardRef(function FieldsetLegend(
-  props: FieldsetLegendProps,
+  props: FieldsetLegend.Props,
   forwardedRef: React.ForwardedRef<HTMLSpanElement>,
 ) {
   const { render, className, id, ...otherProps } = props;
@@ -27,7 +27,7 @@ const FieldsetLegend = React.forwardRef(function FieldsetLegend(
 
   const { disabled } = useFieldsetRootContext();
 
-  const ownerState: FieldsetLegendOwnerState = React.useMemo(
+  const ownerState: FieldsetLegend.OwnerState = React.useMemo(
     () => ({
       disabled: disabled ?? false,
     }),
@@ -46,6 +46,14 @@ const FieldsetLegend = React.forwardRef(function FieldsetLegend(
   return renderElement();
 });
 
+namespace FieldsetLegend {
+  export type OwnerState = {
+    disabled: boolean;
+  };
+
+  export interface Props extends BaseUIComponentProps<'span', OwnerState> {}
+}
+
 FieldsetLegend.propTypes /* remove-proptypes */ = {
   // ┌────────────────────────────── Warning ──────────────────────────────┐
   // │ These PropTypes are generated from the TypeScript type definitions. │
diff --git a/packages/mui-base/src/Fieldset/Legend/FieldsetLegend.types.ts b/packages/mui-base/src/Fieldset/Legend/FieldsetLegend.types.ts
deleted file mode 100644
index 1cb1ed5e18..0000000000
--- a/packages/mui-base/src/Fieldset/Legend/FieldsetLegend.types.ts
+++ /dev/null
@@ -1,8 +0,0 @@
-import type { BaseUIComponentProps } from '../../utils/types';
-
-export type FieldsetLegendOwnerState = {
-  disabled: boolean;
-};
-
-export interface FieldsetLegendProps
-  extends BaseUIComponentProps<'span', FieldsetLegendOwnerState> {}
diff --git a/packages/mui-base/src/Fieldset/Legend/useFieldsetLegend.ts b/packages/mui-base/src/Fieldset/Legend/useFieldsetLegend.ts
index 37aefaa774..2d07e6032b 100644
--- a/packages/mui-base/src/Fieldset/Legend/useFieldsetLegend.ts
+++ b/packages/mui-base/src/Fieldset/Legend/useFieldsetLegend.ts
@@ -5,11 +5,7 @@ import { useId } from '../../utils/useId';
 import { useEnhancedEffect } from '../../utils/useEnhancedEffect';
 import { useFieldsetRootContext } from '../Root/FieldsetRootContext';
 
-interface UseFieldsetLegendParameters {
-  id?: string;
-}
-
-export function useFieldsetLegend(params: UseFieldsetLegendParameters) {
+export function useFieldsetLegend(params: useFieldsetLegend.Parameters) {
   const { id: idProp } = params;
 
   const { setLegendId } = useFieldsetRootContext();
@@ -38,3 +34,9 @@ export function useFieldsetLegend(params: UseFieldsetLegendParameters) {
     [getLegendProps],
   );
 }
+
+export namespace useFieldsetLegend {
+  export interface Parameters {
+    id?: string;
+  }
+}
diff --git a/packages/mui-base/src/Fieldset/Root/FieldsetRoot.tsx b/packages/mui-base/src/Fieldset/Root/FieldsetRoot.tsx
index ba657b9e3a..74a47b859b 100644
--- a/packages/mui-base/src/Fieldset/Root/FieldsetRoot.tsx
+++ b/packages/mui-base/src/Fieldset/Root/FieldsetRoot.tsx
@@ -1,10 +1,10 @@
 'use client';
 import * as React from 'react';
 import PropTypes from 'prop-types';
-import type { FieldsetRootOwnerState, FieldsetRootProps } from './FieldsetRoot.types';
 import { useComponentRenderer } from '../../utils/useComponentRenderer';
-import { FieldsetRootContext, type FieldsetRootContextValue } from './FieldsetRootContext';
+import { FieldsetRootContext } from './FieldsetRootContext';
 import { useFieldsetRoot } from './useFieldsetRoot';
+import type { BaseUIComponentProps } from '../../utils/types';
 
 /**
  * The foundation for building custom-styled fieldsets.
@@ -18,14 +18,14 @@ import { useFieldsetRoot } from './useFieldsetRoot';
  * - [FieldsetRoot API](https://base-ui.netlify.app/components/react-fieldset/#api-reference-FieldsetRoot)
  */
 const FieldsetRoot = React.forwardRef(function FieldsetRoot(
-  props: FieldsetRootProps,
+  props: FieldsetRoot.Props,
   forwardedRef: React.ForwardedRef<HTMLFieldSetElement>,
 ) {
   const { render, className, disabled = false, ...otherProps } = props;
 
   const { legendId, setLegendId, getRootProps } = useFieldsetRoot();
 
-  const ownerState: FieldsetRootOwnerState = React.useMemo(
+  const ownerState: FieldsetRoot.OwnerState = React.useMemo(
     () => ({
       disabled,
     }),
@@ -41,7 +41,7 @@ const FieldsetRoot = React.forwardRef(function FieldsetRoot(
     extraProps: otherProps,
   });
 
-  const contextValue: FieldsetRootContextValue = React.useMemo(
+  const contextValue: FieldsetRootContext = React.useMemo(
     () => ({
       legendId,
       setLegendId,
@@ -57,6 +57,14 @@ const FieldsetRoot = React.forwardRef(function FieldsetRoot(
   );
 });
 
+namespace FieldsetRoot {
+  export type OwnerState = {
+    disabled: boolean;
+  };
+
+  export interface Props extends BaseUIComponentProps<'fieldset', OwnerState> {}
+}
+
 FieldsetRoot.propTypes /* remove-proptypes */ = {
   // ┌────────────────────────────── Warning ──────────────────────────────┐
   // │ These PropTypes are generated from the TypeScript type definitions. │
diff --git a/packages/mui-base/src/Fieldset/Root/FieldsetRoot.types.ts b/packages/mui-base/src/Fieldset/Root/FieldsetRoot.types.ts
deleted file mode 100644
index 5405138555..0000000000
--- a/packages/mui-base/src/Fieldset/Root/FieldsetRoot.types.ts
+++ /dev/null
@@ -1,8 +0,0 @@
-import type { BaseUIComponentProps } from '../../utils/types';
-
-export type FieldsetRootOwnerState = {
-  disabled: boolean;
-};
-
-export interface FieldsetRootProps
-  extends BaseUIComponentProps<'fieldset', FieldsetRootOwnerState> {}
diff --git a/packages/mui-base/src/Fieldset/Root/FieldsetRootContext.ts b/packages/mui-base/src/Fieldset/Root/FieldsetRootContext.ts
index 9692eae8b5..80dc08ea3c 100644
--- a/packages/mui-base/src/Fieldset/Root/FieldsetRootContext.ts
+++ b/packages/mui-base/src/Fieldset/Root/FieldsetRootContext.ts
@@ -1,13 +1,13 @@
 'use client';
 import * as React from 'react';
 
-export interface FieldsetRootContextValue {
+export interface FieldsetRootContext {
   legendId: string | undefined;
   setLegendId: React.Dispatch<React.SetStateAction<string | undefined>>;
   disabled: boolean | undefined;
 }
 
-export const FieldsetRootContext = React.createContext<FieldsetRootContextValue>({
+export const FieldsetRootContext = React.createContext<FieldsetRootContext>({
   legendId: undefined,
   setLegendId: () => {},
   disabled: undefined,
diff --git a/packages/mui-base/src/Fieldset/index.barrel.ts b/packages/mui-base/src/Fieldset/index.barrel.ts
index bd5416640a..b5a4cbaf40 100644
--- a/packages/mui-base/src/Fieldset/index.barrel.ts
+++ b/packages/mui-base/src/Fieldset/index.barrel.ts
@@ -1,5 +1,2 @@
 export * from './Root/FieldsetRoot';
 export * from './Legend/FieldsetLegend';
-
-export type * from './Root/FieldsetRoot.types';
-export type * from './Legend/FieldsetLegend.types';
diff --git a/packages/mui-base/src/Fieldset/index.ts b/packages/mui-base/src/Fieldset/index.ts
index 9d2e949e67..ee2ae05cbc 100644
--- a/packages/mui-base/src/Fieldset/index.ts
+++ b/packages/mui-base/src/Fieldset/index.ts
@@ -1,11 +1,2 @@
 export { FieldsetRoot as Root } from './Root/FieldsetRoot';
 export { FieldsetLegend as Legend } from './Legend/FieldsetLegend';
-
-export type {
-  FieldsetRootProps as RootProps,
-  FieldsetRootOwnerState as RootOwnerState,
-} from './Root/FieldsetRoot.types';
-export type {
-  FieldsetLegendProps as LegendProps,
-  FieldsetLegendOwnerState as LegendOwnerState,
-} from './Legend/FieldsetLegend.types';