diff --git a/.babelrc.js b/.babelrc.js
index 4067bd1..d44cdb1 100644
--- a/.babelrc.js
+++ b/.babelrc.js
@@ -1,4 +1,4 @@
-module.exports = (api) => ({
+export default (api) => ({
   presets: [
     ['env-modules', { modules: api.env() === 'cjs' ? 'commonjs' : false }],
     ['@babel/react', { runtime: 'automatic' }],
diff --git a/eslint.config.mjs b/eslint.config.mjs
index a96b397..0aa3eb4 100644
--- a/eslint.config.mjs
+++ b/eslint.config.mjs
@@ -55,6 +55,7 @@ export default tseslint.config(
           ignoreRestSiblings: false,
         },
       ],
+      'react/prop-types': 'off',
     },
   },
   {
@@ -82,7 +83,6 @@ export default tseslint.config(
       '@typescript-eslint/no-unused-expressions': 'off',
       'padded-blocks': 'off',
       'react/no-multi-comp': 'off',
-      'react/prop-types': 'off',
     },
   },
 );
diff --git a/package.json b/package.json
index f4881d9..ed57770 100644
--- a/package.json
+++ b/package.json
@@ -11,7 +11,8 @@
     "url": "git+https://github.com/react-restart/ui.git"
   },
   "license": "MIT",
-  "main": "cjs/index.js",
+  "type": "module",
+  "main": "lib/index.js",
   "module": "lib/index.js",
   "types": "lib/index.d.ts",
   "exports": {
@@ -100,7 +101,7 @@
     "@restart/hooks": "^0.6.2",
     "@types/warning": "^3.0.3",
     "dequal": "^2.0.3",
-    "dom-helpers": "^5.2.0",
+    "dom-helpers": "^6.0.1",
     "uncontrollable": "^9.0.0",
     "warning": "^4.0.3"
   },
diff --git a/src/Anchor.tsx b/src/Anchor.tsx
index 2ff615d..f1a9a6c 100644
--- a/src/Anchor.tsx
+++ b/src/Anchor.tsx
@@ -1,7 +1,7 @@
 import * as React from 'react';
 
 import useEventCallback from '@restart/hooks/useEventCallback';
-import { useButtonProps } from './Button';
+import { useButtonProps } from './Button.js';
 
 export function isTrivialHref(href?: string) {
   return !href || href.trim() === '#';
diff --git a/src/Dropdown.tsx b/src/Dropdown.tsx
index 4acfb62..271a911 100644
--- a/src/Dropdown.tsx
+++ b/src/Dropdown.tsx
@@ -8,23 +8,23 @@ import useForceUpdate from '@restart/hooks/useForceUpdate';
 import useEventListener from '@restart/hooks/useEventListener';
 import useEventCallback from '@restart/hooks/useEventCallback';
 
-import DropdownContext from './DropdownContext';
+import DropdownContext from './DropdownContext.js';
 import DropdownMenu, {
-  DropdownMenuProps,
-  UseDropdownMenuMetadata,
-  UseDropdownMenuOptions,
-} from './DropdownMenu';
+  type DropdownMenuProps,
+  type UseDropdownMenuMetadata,
+  type UseDropdownMenuOptions,
+} from './DropdownMenu.js';
 import DropdownToggle, {
-  DropdownToggleProps,
-  UseDropdownToggleMetadata,
+  type DropdownToggleProps,
+  type UseDropdownToggleMetadata,
   isRoleMenu,
-} from './DropdownToggle';
-import DropdownItem, { DropdownItemProps } from './DropdownItem';
-import SelectableContext from './SelectableContext';
-import { SelectCallback } from './types';
-import { dataAttr } from './DataKey';
-import { Placement } from './usePopper';
-import useWindow from './useWindow';
+} from './DropdownToggle.js';
+import DropdownItem, { type DropdownItemProps } from './DropdownItem.js';
+import SelectableContext from './SelectableContext.js';
+import type { SelectCallback } from './types.js';
+import { dataAttr } from './DataKey.js';
+import type { Placement } from './usePopper.js';
+import useWindow from './useWindow.js';
 
 export type {
   DropdownMenuProps,
diff --git a/src/DropdownContext.ts b/src/DropdownContext.ts
index 94bf89f..5421a6e 100644
--- a/src/DropdownContext.ts
+++ b/src/DropdownContext.ts
@@ -1,5 +1,5 @@
 import * as React from 'react';
-import type { Placement } from './usePopper';
+import type { Placement } from './usePopper.js';
 
 export type DropdownContextValue = {
   toggle: (
diff --git a/src/DropdownItem.tsx b/src/DropdownItem.tsx
index 95cb8ee..f4e8113 100644
--- a/src/DropdownItem.tsx
+++ b/src/DropdownItem.tsx
@@ -2,12 +2,12 @@ import * as React from 'react';
 import { useContext } from 'react';
 import useEventCallback from '@restart/hooks/useEventCallback';
 
-import SelectableContext, { makeEventKey } from './SelectableContext';
-import NavContext from './NavContext';
+import SelectableContext, { makeEventKey } from './SelectableContext.js';
+import NavContext from './NavContext.js';
 
-import { EventKey, DynamicRefForwardingComponent } from './types';
-import Button from './Button';
-import { dataAttr } from './DataKey';
+import type { EventKey, DynamicRefForwardingComponent } from './types.js';
+import Button from './Button.js';
+import { dataAttr } from './DataKey.js';
 
 export interface DropdownItemProps extends React.HTMLAttributes<HTMLElement> {
   /**
diff --git a/src/DropdownMenu.tsx b/src/DropdownMenu.tsx
index 3afef73..b511fd6 100644
--- a/src/DropdownMenu.tsx
+++ b/src/DropdownMenu.tsx
@@ -1,15 +1,19 @@
 import { useContext, useRef } from 'react';
 import * as React from 'react';
 import useCallbackRef from '@restart/hooks/useCallbackRef';
-import DropdownContext, { DropdownContextValue } from './DropdownContext';
+import DropdownContext, {
+  type DropdownContextValue,
+} from './DropdownContext.js';
 import usePopper, {
-  UsePopperOptions,
-  Placement,
-  Offset,
-  UsePopperState,
-} from './usePopper';
-import useClickOutside, { ClickOutsideOptions } from './useClickOutside';
-import mergeOptionsWithPopperConfig from './mergeOptionsWithPopperConfig';
+  type UsePopperOptions,
+  type Placement,
+  type Offset,
+  type UsePopperState,
+} from './usePopper.js';
+import useClickOutside, {
+  type ClickOutsideOptions,
+} from './useClickOutside.js';
+import mergeOptionsWithPopperConfig from './mergeOptionsWithPopperConfig.js';
 
 export interface UseDropdownMenuOptions {
   /**
diff --git a/src/DropdownToggle.tsx b/src/DropdownToggle.tsx
index 030ad7b..7e9f872 100644
--- a/src/DropdownToggle.tsx
+++ b/src/DropdownToggle.tsx
@@ -1,6 +1,8 @@
 import { useContext, useCallback, useId } from 'react';
 import * as React from 'react';
-import DropdownContext, { DropdownContextValue } from './DropdownContext';
+import DropdownContext, {
+  type DropdownContextValue,
+} from './DropdownContext.js';
 
 export const isRoleMenu = (el: HTMLElement) =>
   el.getAttribute('role')?.toLowerCase() === 'menu';
diff --git a/src/ImperativeTransition.tsx b/src/ImperativeTransition.tsx
index ac2559f..d580286 100644
--- a/src/ImperativeTransition.tsx
+++ b/src/ImperativeTransition.tsx
@@ -2,10 +2,10 @@ import useMergedRefs from '@restart/hooks/useMergedRefs';
 import useEventCallback from '@restart/hooks/useEventCallback';
 import useIsomorphicEffect from '@restart/hooks/useIsomorphicEffect';
 import { useRef, cloneElement, useState } from 'react';
-import { TransitionComponent, TransitionProps } from './types';
-import NoopTransition from './NoopTransition';
-import RTGTransition from './RTGTransition';
-import { getChildRef } from './utils';
+import type { TransitionComponent, TransitionProps } from './types.js';
+import NoopTransition from './NoopTransition.js';
+import RTGTransition from './RTGTransition.js';
+import { getChildRef } from './utils.js';
 
 export interface TransitionFunctionOptions {
   in: boolean;
diff --git a/src/Modal.tsx b/src/Modal.tsx
index 78c3cb9..7342d8f 100644
--- a/src/Modal.tsx
+++ b/src/Modal.tsx
@@ -1,5 +1,3 @@
-/* eslint-disable react/prop-types */
-
 import activeElement from 'dom-helpers/activeElement';
 import contains from 'dom-helpers/contains';
 import canUseDOM from 'dom-helpers/canUseDOM';
@@ -19,12 +17,15 @@ import useWillUnmount from '@restart/hooks/useWillUnmount';
 
 import usePrevious from '@restart/hooks/usePrevious';
 import useEventCallback from '@restart/hooks/useEventCallback';
-import ModalManager from './ModalManager';
-import useWaitForDOMRef, { DOMContainer } from './useWaitForDOMRef';
-import { TransitionCallbacks, TransitionComponent } from './types';
-import useWindow from './useWindow';
-import { renderTransition, TransitionHandler } from './ImperativeTransition';
-import { isEscKey } from './utils';
+import ModalManager from './ModalManager.js';
+import useWaitForDOMRef, { type DOMContainer } from './useWaitForDOMRef.js';
+import type { TransitionCallbacks, TransitionComponent } from './types.js';
+import useWindow from './useWindow.js';
+import {
+  renderTransition,
+  type TransitionHandler,
+} from './ImperativeTransition.js';
+import { isEscKey } from './utils.js';
 
 let manager: ModalManager;
 
diff --git a/src/ModalManager.ts b/src/ModalManager.ts
index fbab930..70f7cf1 100644
--- a/src/ModalManager.ts
+++ b/src/ModalManager.ts
@@ -1,6 +1,6 @@
 import css from 'dom-helpers/css';
-import { dataAttr } from './DataKey';
-import getBodyScrollbarWidth from './getScrollbarWidth';
+import { dataAttr } from './DataKey.js';
+import getBodyScrollbarWidth from './getScrollbarWidth.js';
 
 export interface ModalInstance {
   dialog: Element;
diff --git a/src/Nav.tsx b/src/Nav.tsx
index 91feced..1db6545 100644
--- a/src/Nav.tsx
+++ b/src/Nav.tsx
@@ -3,16 +3,19 @@ import * as React from 'react';
 import { useContext, useEffect, useRef } from 'react';
 import useForceUpdate from '@restart/hooks/useForceUpdate';
 import useMergedRefs from '@restart/hooks/useMergedRefs';
-import NavContext from './NavContext';
-import SelectableContext, { makeEventKey } from './SelectableContext';
-import TabContext from './TabContext';
-import {
+import NavContext from './NavContext.js';
+import SelectableContext, { makeEventKey } from './SelectableContext.js';
+import TabContext from './TabContext.js';
+import type {
   EventKey,
   DynamicRefForwardingComponent,
   SelectCallback,
-} from './types';
-import { dataAttr, dataProp } from './DataKey';
-import NavItem, { UseNavItemOptions, NavItemProps } from './NavItem';
+} from './types.js';
+import { dataAttr, dataProp } from './DataKey.js';
+import NavItem, {
+  type UseNavItemOptions,
+  type NavItemProps,
+} from './NavItem.js';
 
 export type { UseNavItemOptions, NavItemProps };
 
diff --git a/src/NavContext.tsx b/src/NavContext.tsx
index eceae8c..f6ec13c 100644
--- a/src/NavContext.tsx
+++ b/src/NavContext.tsx
@@ -1,5 +1,5 @@
 import * as React from 'react';
-import { EventKey } from './types';
+import type { EventKey } from './types.js';
 
 interface NavContextType {
   role?: string; // used by NavItem to determine it's role
diff --git a/src/NavItem.tsx b/src/NavItem.tsx
index 0ab4c42..f082a12 100644
--- a/src/NavItem.tsx
+++ b/src/NavItem.tsx
@@ -2,12 +2,12 @@ import * as React from 'react';
 import { useContext } from 'react';
 import useEventCallback from '@restart/hooks/useEventCallback';
 
-import NavContext from './NavContext';
-import SelectableContext, { makeEventKey } from './SelectableContext';
-import { EventKey, DynamicRefForwardingComponent } from './types';
-import Button from './Button';
-import { dataAttr } from './DataKey';
-import TabContext from './TabContext';
+import NavContext from './NavContext.js';
+import SelectableContext, { makeEventKey } from './SelectableContext.js';
+import type { EventKey, DynamicRefForwardingComponent } from './types.js';
+import Button from './Button.js';
+import { dataAttr } from './DataKey.js';
+import TabContext from './TabContext.js';
 
 export interface NavItemProps extends React.HTMLAttributes<HTMLElement> {
   /**
diff --git a/src/NoopTransition.tsx b/src/NoopTransition.tsx
index d4f1983..56a1b09 100644
--- a/src/NoopTransition.tsx
+++ b/src/NoopTransition.tsx
@@ -1,8 +1,8 @@
 import useEventCallback from '@restart/hooks/useEventCallback';
 import useMergedRefs from '@restart/hooks/useMergedRefs';
 import { cloneElement, useEffect, useRef } from 'react';
-import { TransitionProps } from './types';
-import { getChildRef } from './utils';
+import type { TransitionProps } from './types.js';
+import { getChildRef } from './utils.js';
 
 function NoopTransition({
   children,
diff --git a/src/Overlay.tsx b/src/Overlay.tsx
index 1e7ffb2..f5baf9d 100644
--- a/src/Overlay.tsx
+++ b/src/Overlay.tsx
@@ -4,17 +4,20 @@ import useCallbackRef from '@restart/hooks/useCallbackRef';
 import useMergedRefs from '@restart/hooks/useMergedRefs';
 import { useState } from 'react';
 import usePopper, {
-  Offset,
-  Placement,
-  UsePopperOptions,
-  UsePopperState,
-  VirtualElement,
-} from './usePopper';
-import useRootClose, { RootCloseOptions } from './useRootClose';
-import useWaitForDOMRef, { DOMContainer } from './useWaitForDOMRef';
-import { TransitionCallbacks, TransitionComponent } from './types';
-import mergeOptionsWithPopperConfig from './mergeOptionsWithPopperConfig';
-import { renderTransition, TransitionHandler } from './ImperativeTransition';
+  type Offset,
+  type Placement,
+  type UsePopperOptions,
+  type UsePopperState,
+  type VirtualElement,
+} from './usePopper.js';
+import useRootClose, { type RootCloseOptions } from './useRootClose.js';
+import useWaitForDOMRef, { type DOMContainer } from './useWaitForDOMRef.js';
+import type { TransitionCallbacks, TransitionComponent } from './types.js';
+import mergeOptionsWithPopperConfig from './mergeOptionsWithPopperConfig.js';
+import {
+  renderTransition,
+  type TransitionHandler,
+} from './ImperativeTransition.js';
 
 export interface OverlayArrowProps extends Record<string, any> {
   ref: React.RefCallback<HTMLElement>;
diff --git a/src/Portal.tsx b/src/Portal.tsx
index 92a200f..474dac0 100644
--- a/src/Portal.tsx
+++ b/src/Portal.tsx
@@ -1,7 +1,7 @@
 import ReactDOM from 'react-dom';
 
 import * as React from 'react';
-import useWaitForDOMRef, { DOMContainer } from './useWaitForDOMRef';
+import useWaitForDOMRef, { type DOMContainer } from './useWaitForDOMRef.js';
 
 export interface PortalProps {
   children: React.ReactElement;
diff --git a/src/RTGTransition.tsx b/src/RTGTransition.tsx
index 068bfc4..b45d25e 100644
--- a/src/RTGTransition.tsx
+++ b/src/RTGTransition.tsx
@@ -1,7 +1,7 @@
 import * as React from 'react';
 import useRTGTransitionProps, {
-  TransitionProps,
-} from './useRTGTransitionProps';
+  type TransitionProps,
+} from './useRTGTransitionProps.js';
 
 export type RTGTransitionProps = TransitionProps & {
   component: React.ElementType;
diff --git a/src/SelectableContext.tsx b/src/SelectableContext.tsx
index f25ebe9..6fa3937 100644
--- a/src/SelectableContext.tsx
+++ b/src/SelectableContext.tsx
@@ -1,5 +1,5 @@
 import * as React from 'react';
-import { EventKey, SelectCallback } from './types';
+import type { EventKey, SelectCallback } from './types.js';
 
 const SelectableContext = React.createContext<SelectCallback | null>(null);
 
diff --git a/src/TabContext.tsx b/src/TabContext.tsx
index e64809c..668e720 100644
--- a/src/TabContext.tsx
+++ b/src/TabContext.tsx
@@ -1,5 +1,5 @@
 import * as React from 'react';
-import { EventKey, SelectCallback, TransitionComponent } from './types';
+import type { EventKey, SelectCallback, TransitionComponent } from './types.js';
 
 export interface TabContextType {
   onSelect: SelectCallback;
diff --git a/src/TabPanel.tsx b/src/TabPanel.tsx
index d2af7bd..960881f 100644
--- a/src/TabPanel.tsx
+++ b/src/TabPanel.tsx
@@ -1,15 +1,15 @@
 import * as React from 'react';
 import { useContext } from 'react';
 
-import TabContext from './TabContext';
-import SelectableContext, { makeEventKey } from './SelectableContext';
-import {
+import TabContext from './TabContext.js';
+import SelectableContext, { makeEventKey } from './SelectableContext.js';
+import type {
   EventKey,
   DynamicRefForwardingComponent,
   TransitionCallbacks,
   TransitionComponent,
-} from './types';
-import NoopTransition from './NoopTransition';
+} from './types.js';
+import NoopTransition from './NoopTransition.js';
 
 export interface TabPanelProps
   extends TransitionCallbacks,
diff --git a/src/Tabs.tsx b/src/Tabs.tsx
index 61741e2..6485a08 100644
--- a/src/Tabs.tsx
+++ b/src/Tabs.tsx
@@ -2,10 +2,10 @@ import * as React from 'react';
 import { useId, useMemo } from 'react';
 import { useUncontrolledProp } from 'uncontrollable';
 
-import TabContext, { TabContextType } from './TabContext';
-import SelectableContext from './SelectableContext';
-import { EventKey, SelectCallback, TransitionComponent } from './types';
-import TabPanel, { TabPanelProps } from './TabPanel';
+import TabContext, { type TabContextType } from './TabContext.js';
+import SelectableContext from './SelectableContext.js';
+import { EventKey, SelectCallback, TransitionComponent } from './types.js';
+import TabPanel, { TabPanelProps } from './TabPanel.js';
 
 export type { TabPanelProps };
 export interface TabsProps extends React.PropsWithChildren<unknown> {
diff --git a/src/Waypoint.tsx b/src/Waypoint.tsx
index 4dab2e4..451d5ee 100644
--- a/src/Waypoint.tsx
+++ b/src/Waypoint.tsx
@@ -2,10 +2,10 @@ import useCallbackRef from '@restart/hooks/useCallbackRef';
 import * as React from 'react';
 
 import useWaypoint, {
-  WaypointOptions,
-  WaypointEvent,
-  Position,
-} from './useWaypoint';
+  type WaypointOptions,
+  type WaypointEvent,
+  type Position,
+} from './useWaypoint.js';
 
 export { Position };
 export type { WaypointEvent };
diff --git a/src/index.ts b/src/index.ts
index 0717963..ddb3f59 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,16 +1,16 @@
-import Dropdown from './Dropdown';
-import { useDropdownMenu } from './DropdownMenu';
-import { useDropdownToggle } from './DropdownToggle';
-import { useDropdownItem } from './DropdownItem';
-import Modal from './Modal';
-import Overlay from './Overlay';
-import Portal from './Portal';
-import useRootClose from './useRootClose';
-import Nav from './Nav';
-import NavItem, { useNavItem } from './NavItem';
-import Button from './Button';
-import Tabs from './Tabs';
-import TabPanel from './TabPanel';
+import Dropdown from './Dropdown.js';
+import { useDropdownMenu } from './DropdownMenu.js';
+import { useDropdownToggle } from './DropdownToggle.js';
+import { useDropdownItem } from './DropdownItem.js';
+import Modal from './Modal.js';
+import Overlay from './Overlay.js';
+import Portal from './Portal.js';
+import useRootClose from './useRootClose.js';
+import Nav from './Nav.js';
+import NavItem, { useNavItem } from './NavItem.js';
+import Button from './Button.js';
+import Tabs from './Tabs.js';
+import TabPanel from './TabPanel.js';
 
 export {
   Button,
@@ -29,7 +29,7 @@ export {
   TabPanel,
 };
 
-export type { ButtonProps } from './Button';
+export type { ButtonProps } from './Button.js';
 export type {
   DropdownProps,
   DropdownMenuProps,
@@ -38,9 +38,9 @@ export type {
   DropdownToggleProps,
   UseDropdownToggleMetadata,
   DropdownItemProps,
-} from './Dropdown';
-export type { NavItemProps, UseNavItemOptions, NavProps } from './Nav';
-export type { ModalProps } from './Modal';
-export type { OverlayProps } from './Overlay';
-export type { PortalProps } from './Portal';
-export type { TabsProps, TabPanelProps } from './Tabs';
+} from './Dropdown.js';
+export type { NavItemProps, UseNavItemOptions, NavProps } from './Nav.js';
+export type { ModalProps } from './Modal.js';
+export type { OverlayProps } from './Overlay.js';
+export type { PortalProps } from './Portal.js';
+export type { TabsProps, TabPanelProps } from './Tabs.js';
diff --git a/src/mergeOptionsWithPopperConfig.ts b/src/mergeOptionsWithPopperConfig.ts
index 501fff8..b1c4ef2 100644
--- a/src/mergeOptionsWithPopperConfig.ts
+++ b/src/mergeOptionsWithPopperConfig.ts
@@ -1,4 +1,9 @@
-import { UsePopperOptions, Offset, Placement, Modifiers } from './usePopper';
+import type {
+  UsePopperOptions,
+  Offset,
+  Placement,
+  Modifiers,
+} from './usePopper.js';
 
 export type Config = {
   flip?: boolean;
diff --git a/src/popper.ts b/src/popper.ts
index ed0ec6b..758294f 100644
--- a/src/popper.ts
+++ b/src/popper.ts
@@ -1,13 +1,17 @@
-import arrow from '@popperjs/core/lib/modifiers/arrow';
-import computeStyles from '@popperjs/core/lib/modifiers/computeStyles';
-import eventListeners from '@popperjs/core/lib/modifiers/eventListeners';
-import flip from '@popperjs/core/lib/modifiers/flip';
-import hide from '@popperjs/core/lib/modifiers/hide';
-import offset from '@popperjs/core/lib/modifiers/offset';
-import popperOffsets from '@popperjs/core/lib/modifiers/popperOffsets';
-import preventOverflow from '@popperjs/core/lib/modifiers/preventOverflow';
-import { placements } from '@popperjs/core/lib/enums';
-import { popperGenerator } from '@popperjs/core/lib/popper-base';
+// Since tsconfig is set for nodenext, these imports are resolving with a { default: ... } object, which
+// messes up the types.
+// eslint-disable-next-line @typescript-eslint/ban-ts-comment
+// @ts-nocheck
+import arrow from '@popperjs/core/lib/modifiers/arrow.js';
+import computeStyles from '@popperjs/core/lib/modifiers/computeStyles.js';
+import eventListeners from '@popperjs/core/lib/modifiers/eventListeners.js';
+import flip from '@popperjs/core/lib/modifiers/flip.js';
+import hide from '@popperjs/core/lib/modifiers/hide.js';
+import offset from '@popperjs/core/lib/modifiers/offset.js';
+import popperOffsets from '@popperjs/core/lib/modifiers/popperOffsets.js';
+import preventOverflow from '@popperjs/core/lib/modifiers/preventOverflow.js';
+import { placements } from '@popperjs/core/lib/enums.js';
+import { popperGenerator } from '@popperjs/core/lib/popper-base.js';
 
 // For the common JS build we will turn this file into a bundle with no imports.
 // This is b/c the Popper lib is all esm files, and would break in a common js only environment
diff --git a/src/usePopper.ts b/src/usePopper.ts
index a357781..7b3e0d9 100644
--- a/src/usePopper.ts
+++ b/src/usePopper.ts
@@ -2,7 +2,7 @@ import * as Popper from '@popperjs/core';
 import { useCallback, useEffect, useMemo, useRef, useState } from 'react';
 import { dequal } from 'dequal';
 import useSafeState from '@restart/hooks/useSafeState';
-import { createPopper } from './popper';
+import { createPopper } from './popper.js';
 
 const disabledApplyStylesModifier = {
   name: 'applyStyles',
diff --git a/src/useRTGTransitionProps.ts b/src/useRTGTransitionProps.ts
index 0c46f6e..3003759 100644
--- a/src/useRTGTransitionProps.ts
+++ b/src/useRTGTransitionProps.ts
@@ -1,10 +1,10 @@
 import { cloneElement, useCallback, useRef } from 'react';
 import useMergedRefs from '@restart/hooks/useMergedRefs';
-import {
+import type {
   TransitionProps as RTGTransitionProps,
   TransitionStatus,
-} from 'react-transition-group/Transition';
-import { getChildRef } from './utils';
+} from 'react-transition-group/Transition.js';
+import { getChildRef } from './utils.js';
 
 export type TransitionProps = RTGTransitionProps & {
   children:
diff --git a/src/useRootClose.ts b/src/useRootClose.ts
index 33db5b3..991f21f 100644
--- a/src/useRootClose.ts
+++ b/src/useRootClose.ts
@@ -4,10 +4,10 @@ import { useEffect } from 'react';
 
 import useEventCallback from '@restart/hooks/useEventCallback';
 import useClickOutside, {
-  ClickOutsideOptions,
+  type ClickOutsideOptions,
   getRefTarget,
-} from './useClickOutside';
-import { isEscKey } from './utils';
+} from './useClickOutside.js';
+import { isEscKey } from './utils.js';
 
 const noop = () => {};
 
diff --git a/src/useWaitForDOMRef.ts b/src/useWaitForDOMRef.ts
index 40a6b8a..e77f79f 100644
--- a/src/useWaitForDOMRef.ts
+++ b/src/useWaitForDOMRef.ts
@@ -1,8 +1,8 @@
 import ownerDocument from 'dom-helpers/ownerDocument';
 import canUseDOM from 'dom-helpers/canUseDOM';
 import { useState, useEffect } from 'react';
-import useWindow from './useWindow';
-import { VirtualElement } from './usePopper';
+import useWindow from './useWindow.js';
+import type { VirtualElement } from './usePopper.js';
 
 export type DOMContainer<T extends HTMLElement | VirtualElement = HTMLElement> =
 
diff --git a/tsconfig.json b/tsconfig.json
index f6d38e6..4aafba8 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -5,8 +5,8 @@
     "skipLibCheck": true,
     "lib": ["esnext", "dom"],
     "target": "esnext",
-    "module": "esnext",
-    "moduleResolution": "bundler",
+    "module": "NodeNext",
+    "moduleResolution": "NodeNext",
     "allowJs": true,
     "allowSyntheticDefaultImports": true,
     "esModuleInterop": true,
diff --git a/www/plugins/webpack.js b/www/plugins/webpack.js
index 1f98818..4524503 100644
--- a/www/plugins/webpack.js
+++ b/www/plugins/webpack.js
@@ -24,6 +24,9 @@ module.exports = () => ({
         alias: {
           '@restart/ui': path.resolve(__dirname, '../../src'),
         },
+        extensionAlias: {
+          '.js': ['.ts', '.tsx', '.js'],
+        },
       },
     };
   },
diff --git a/yarn.lock b/yarn.lock
index 5dd7de1..7da3e56 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1549,6 +1549,11 @@
   dependencies:
     regenerator-runtime "^0.14.0"
 
+"@babel/runtime@^7.27.1":
+  version "7.27.6"
+  resolved "https://registry.yarnpkg.com/@babel/runtime/-/runtime-7.27.6.tgz#ec4070a04d76bae8ddbb10770ba55714a417b7c6"
+  integrity sha512-vbavdySgbTTrmFE+EsiqUTzlOr5bzlnJtUv9PynGCAKvfQqjIXbvFdumPM/GxMDfyuGMJaJAU6TO4zc1Jf1i8Q==
+
 "@babel/runtime@^7.5.5", "@babel/runtime@^7.8.4", "@babel/runtime@^7.8.7":
   version "7.21.0"
   resolved "https://registry.yarnpkg.com/@babel/runtime/-/runtime-7.21.0.tgz#5b55c9d394e5fcf304909a8b00c07dc217b56673"
@@ -4130,6 +4135,11 @@ csstype@^3.0.2:
   resolved "https://registry.yarnpkg.com/csstype/-/csstype-3.0.8.tgz#d2266a792729fb227cd216fb572f43728e1ad340"
   integrity sha512-jXKhWqXPmlUeoQnF/EhTtTl4C9SnrxSH/jZUih3jmO6lBKr99rP3/+FmrMj4EFpOXzMtXHAZkd3x0E6h6Fgflw==
 
+csstype@^3.1.3:
+  version "3.1.3"
+  resolved "https://registry.yarnpkg.com/csstype/-/csstype-3.1.3.tgz#d80ff294d114fb0e6ac500fbf85b60137d7eff81"
+  integrity sha512-M1uQkMl8rQK/szD0LNhtqxIPLpimGm8sOBwU7lLnCpSbTyY3yeU1Vc7l4KT5zT4s/yOxHH5O7tIuuLOCnLADRw==
+
 dargs@^7.0.0:
   version "7.0.0"
   resolved "https://registry.yarnpkg.com/dargs/-/dargs-7.0.0.tgz#04015c41de0bcb69ec84050f3d9be0caf8d6d5cc"
@@ -4428,7 +4438,7 @@ dom-accessibility-api@^0.5.9:
   resolved "https://registry.yarnpkg.com/dom-accessibility-api/-/dom-accessibility-api-0.5.16.tgz#5a7429e6066eb3664d911e33fb0e45de8eb08453"
   integrity sha512-X7BJ2yElsnOJ30pZF4uIIDfBEVgF4XEBxL9Bxhy6dnrm5hkzqmsWHGTiHqRiITNhMyFLyAiWndIJP7Z1NTteDg==
 
-dom-helpers@^5.0.1, dom-helpers@^5.2.0:
+dom-helpers@^5.0.1:
   version "5.2.1"
   resolved "https://registry.yarnpkg.com/dom-helpers/-/dom-helpers-5.2.1.tgz#d9400536b2bf8225ad98fe052e029451ac40e902"
   integrity sha512-nRCa7CK3VTrM2NmGkIy4cbK7IZlgBE/PYMn55rrXefr5xXDP0LdtfPnblFDoVdcAfslJ7or6iqAUnx0CCGIWQA==
@@ -4436,6 +4446,14 @@ dom-helpers@^5.0.1, dom-helpers@^5.2.0:
     "@babel/runtime" "^7.8.7"
     csstype "^3.0.2"
 
+dom-helpers@^6.0.1:
+  version "6.0.1"
+  resolved "https://registry.yarnpkg.com/dom-helpers/-/dom-helpers-6.0.1.tgz#f56400eb45770e3dd4fa014513739e6b670e6362"
+  integrity sha512-IKySryuFwseGkrCA/pIqlwUPOD50w1Lj/B2Yief3vBOP18k5y4t+hTqKh55gULDVeJMRitcozve+g/wVFf4sFQ==
+  dependencies:
+    "@babel/runtime" "^7.27.1"
+    csstype "^3.1.3"
+
 dom-serializer@^1.0.1:
   version "1.3.2"
   resolved "https://registry.yarnpkg.com/dom-serializer/-/dom-serializer-1.3.2.tgz#6206437d32ceefaec7161803230c7a20bc1b4d91"