diff --git a/.eslintrc.js b/.eslintrc.js
index 2d51c3c05..57826c457 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -52,7 +52,7 @@ module.exports = {
       },
     },
     {
-      files: ["*.ts"],
+      files: ["*.ts", "*.mts"],
       parser: "@typescript-eslint/parser",
       parserOptions: {
         sourceType: "module",
diff --git a/docs-svelte-kit/.eslintrc.cjs b/docs-svelte-kit/.eslintrc.cjs
index bddda3031..20e9b4b96 100644
--- a/docs-svelte-kit/.eslintrc.cjs
+++ b/docs-svelte-kit/.eslintrc.cjs
@@ -1,4 +1,3 @@
-// eslint-disable-next-line no-undef -- ignore
 module.exports = {
   extends: ["plugin:svelte/recommended"],
   env: {
@@ -15,5 +14,6 @@ module.exports = {
     "svelte/prefer-class-directive": "error",
     "svelte/prefer-style-directive": "error",
     "svelte/spaced-html-comment": "error",
+    "node/file-extension-in-import": "off",
   },
 }
diff --git a/docs-svelte-kit/build-system/build.js b/docs-svelte-kit/build-system/build.mts
similarity index 70%
rename from docs-svelte-kit/build-system/build.js
rename to docs-svelte-kit/build-system/build.mts
index b071bf50f..3a335ffe1 100644
--- a/docs-svelte-kit/build-system/build.js
+++ b/docs-svelte-kit/build-system/build.mts
@@ -1,21 +1,28 @@
-const esbuild = require("esbuild")
-const path = require("path")
-const fs = require("fs")
+import esbuild from "esbuild"
+import path from "path"
+import fs from "fs"
 // const babelCore = require("@babel/core")
 // const t = require("@babel/types")
 
+const dirname = path.dirname(
+  new URL(
+    // @ts-expect-error -- Cannot change `module` option
+    import.meta.url,
+  ).pathname,
+)
+
 build(
-  require.resolve("./src/eslint.mjs"),
-  path.join(__dirname, "../shim/eslint.mjs"),
+  path.join(dirname, "./src/eslint.mjs"),
+  path.join(dirname, "../shim/eslint.mjs"),
   ["assert", "util"],
 )
 build(
-  require.resolve("../../node_modules/assert"),
-  path.join(__dirname, "../shim/assert.mjs"),
+  path.join(dirname, "../../node_modules/assert"),
+  path.join(dirname, "../shim/assert.mjs"),
 )
 
 /** build */
-function build(input, out, injects = []) {
+function build(input: string, out: string, injects: string[] = []) {
   // eslint-disable-next-line no-console -- ignore
   console.log(`build@ ${input}`)
   let code = bundle(input, ["path", ...injects])
@@ -24,21 +31,21 @@ function build(input, out, injects = []) {
 }
 
 /** bundle */
-function bundle(entryPoint, externals) {
+function bundle(entryPoint: string, externals: string[]) {
   const result = esbuild.buildSync({
     entryPoints: [entryPoint],
     format: "esm",
     bundle: true,
     external: externals,
     write: false,
-    inject: [require.resolve("./src/process-shim.mjs")],
+    inject: [path.join(dirname, "./src/process-shim.mjs")],
   })
 
   return `${result.outputFiles[0].text}`
 }
 
 /** transform code */
-function transform(code, injects) {
+function transform(code: string, injects: string[]) {
   const newCode = code.replace(/"[a-z]+" = "[a-z]+";/, "")
   // const newCode = babelCore.transformSync(code, {
   //   babelrc: false,
diff --git a/docs-svelte-kit/shim/module.mjs b/docs-svelte-kit/shim/module.mjs
index 6f5e094c7..9e4f5c979 100644
--- a/docs-svelte-kit/shim/module.mjs
+++ b/docs-svelte-kit/shim/module.mjs
@@ -1,7 +1,7 @@
 /* eslint require-jsdoc:0 -- shim */
-function createRequire() {
+function _createRequire() {
   return () => null
 }
 
-export { createRequire }
-export default { createRequire }
+export { _createRequire as createRequire }
+export default { createRequire: _createRequire }
diff --git a/docs-svelte-kit/src/lib/eslint/scripts/linter.js b/docs-svelte-kit/src/lib/eslint/scripts/linter.js
index 85a34939c..334221494 100644
--- a/docs-svelte-kit/src/lib/eslint/scripts/linter.js
+++ b/docs-svelte-kit/src/lib/eslint/scripts/linter.js
@@ -1,8 +1,7 @@
-// eslint-disable-next-line node/file-extension-in-import -- ignore
 import { rules as pluginRules } from "../../../../../src/utils/rules.ts"
 import { Linter } from "eslint"
 import * as svelteEslintParser from "svelte-eslint-parser"
-// eslint-disable-next-line node/file-extension-in-import -- ignore
+
 export { preprocess, postprocess } from "../../../../../src/processor/index.ts"
 
 const linter = new Linter()
diff --git a/docs-svelte-kit/src/lib/utils.js b/docs-svelte-kit/src/lib/utils.js
index 4e7a09460..5cdc53b9f 100644
--- a/docs-svelte-kit/src/lib/utils.js
+++ b/docs-svelte-kit/src/lib/utils.js
@@ -1,4 +1,3 @@
-// eslint-disable-next-line node/file-extension-in-import -- ignore
 import { rules } from "../../../src/utils/rules.ts"
 import { readable, writable } from "svelte/store"
 // eslint-disable-next-line node/no-missing-import -- ignore
diff --git a/docs-svelte-kit/tools/highlight.mjs b/docs-svelte-kit/tools/highlight.mts
similarity index 86%
rename from docs-svelte-kit/tools/highlight.mjs
rename to docs-svelte-kit/tools/highlight.mts
index 0734c43ce..c274aae27 100644
--- a/docs-svelte-kit/tools/highlight.mjs
+++ b/docs-svelte-kit/tools/highlight.mts
@@ -7,12 +7,12 @@ import "prism-svelte"
 loadLanguages(["markup", "css", "javascript"])
 
 /** Wrap pre tag */
-function wrapPre(code, lang) {
+function wrapPre(code: string, lang: string) {
   const htmlCode = lang === "text" ? escapeHtml(code) : code
   return `<pre class="language-${lang}"><code>${htmlCode}</code></pre>`
 }
 
-const EXTENSION_MAPPINGS = {
+const EXTENSION_MAPPINGS: Record<string, string | undefined> = {
   vue: "markup",
   html: "markup",
   svelte: "svelte",
@@ -28,7 +28,7 @@ const EXTENSION_MAPPINGS = {
   rs: "rust",
 }
 
-export default (str, lang) => {
+export default (str: string, lang: string): string => {
   if (!lang) {
     return wrapPre(str, "text")
   }
diff --git a/docs-svelte-kit/tools/markdown-it-auto-inject-components.mjs b/docs-svelte-kit/tools/markdown-it-auto-inject-components.mts
similarity index 79%
rename from docs-svelte-kit/tools/markdown-it-auto-inject-components.mjs
rename to docs-svelte-kit/tools/markdown-it-auto-inject-components.mts
index 0e5c2b1cb..6ec02750e 100644
--- a/docs-svelte-kit/tools/markdown-it-auto-inject-components.mjs
+++ b/docs-svelte-kit/tools/markdown-it-auto-inject-components.mts
@@ -1,13 +1,15 @@
+import type Md from "markdown-it"
+import type Token from "markdown-it/lib/token"
 /**
  * @param {import('markdown-it')} md
  */
-export default (md) => {
+export default (md: Md): void => {
   md.core.ruler.push("auto_inject_components", (state) => {
     const injected = new Set(extractInjectedComponents(state.tokens))
     for (const component of new Set(
       extractComponents(state.tokens, injected),
     )) {
-      const newToken = new state.Token("auto_inject_component")
+      const newToken = new state.Token("auto_inject_component", "", 0)
       newToken.content = `<script>
 import ${component} from '$lib/components/${component}.svelte'
 </script>`
@@ -15,7 +17,7 @@ import ${component} from '$lib/components/${component}.svelte'
     }
 
     /** Extract imported components */
-    function* extractInjectedComponents(tokens) {
+    function* extractInjectedComponents(tokens: Token[]): Iterable<string> {
       for (const token of tokens) {
         if (
           (token.type === "html_inline" || token.type === "html_block") &&
@@ -33,7 +35,10 @@ import ${component} from '$lib/components/${component}.svelte'
     }
 
     /** Extract inject components */
-    function* extractComponents(tokens, injected) {
+    function* extractComponents(
+      tokens: Token[],
+      injected: Set<string>,
+    ): Iterable<string> {
       for (const token of tokens) {
         if (token.type === "html_inline" || token.type === "html_block") {
           const match = /<([A-Z][\w$]*)/u.exec(token.content)
@@ -47,7 +52,7 @@ import ${component} from '$lib/components/${component}.svelte'
       }
     }
   })
-  // eslint-disable-next-line camelcase -- ignore
+
   md.renderer.rules.auto_inject_component = (tokens, idx, _options) => {
     return tokens[idx].content
   }
diff --git a/docs-svelte-kit/tools/markdown-it-container-option.mjs b/docs-svelte-kit/tools/markdown-it-container-option.mts
similarity index 79%
rename from docs-svelte-kit/tools/markdown-it-container-option.mjs
rename to docs-svelte-kit/tools/markdown-it-container-option.mts
index f8dff94f1..f2cabf0cf 100644
--- a/docs-svelte-kit/tools/markdown-it-container-option.mjs
+++ b/docs-svelte-kit/tools/markdown-it-container-option.mts
@@ -1,8 +1,13 @@
+import type containerPlugin from "markdown-it-container"
+type ContainerPluginOption = Parameters<typeof containerPlugin>[2]
 /**
  * Generate markdown-it-container option
  * @see https://github.com/markdown-it/markdown-it-container
  */
-export default (type, defaultTitle = type.toUpperCase()) => {
+export default (
+  type: string,
+  defaultTitle = type.toUpperCase(),
+): ContainerPluginOption => {
   return {
     render(tokens, index) {
       const token = tokens[index]
diff --git a/docs-svelte-kit/tools/markdown-it-markdown.mjs b/docs-svelte-kit/tools/markdown-it-markdown.mts
similarity index 72%
rename from docs-svelte-kit/tools/markdown-it-markdown.mjs
rename to docs-svelte-kit/tools/markdown-it-markdown.mts
index 17123c999..81b750e74 100644
--- a/docs-svelte-kit/tools/markdown-it-markdown.mjs
+++ b/docs-svelte-kit/tools/markdown-it-markdown.mts
@@ -1,15 +1,24 @@
 import path from "path"
 import spawn from "cross-spawn"
+import type Md from "markdown-it"
+
+type TreeItem = {
+  children: TreeItem[]
+}
+type TreeStack = { item: TreeItem; level: number; upper: TreeStack | null }
 
 class TOCRenderer {
-  constructor(name) {
-    const item = { children: [] }
+  private readonly tree: TreeItem
+
+  private stack: TreeStack
+
+  public constructor() {
+    const item: TreeItem = { children: [] }
     this.tree = item
     this.stack = { item, level: 1, upper: null }
-    this.name = name
   }
 
-  addMenu(level, id, title) {
+  public addMenu(level: number, id: string, title: string) {
     if (this.stack.level < level) {
       const parent = this.stack.item
       const item = parent.children[parent.children.length - 1]
@@ -24,19 +33,19 @@ class TOCRenderer {
     this.stack.item.children.push(item)
   }
 
-  toc() {
+  public toc() {
     return this.tree
   }
 }
 /**
  * @param {import('markdown-it')} md
  */
-export default (md) => {
+export default (md: Md): void => {
   md.core.ruler.push("custom_markdown", (state) => {
     const tokens = state.tokens
-    tokens.unshift(new state.Token("custom_markdown_data"))
+    tokens.unshift(new state.Token("custom_markdown_data", "", 0))
   })
-  // eslint-disable-next-line camelcase -- ignore
+
   md.renderer.rules.custom_markdown_data = (
     tokens,
     _idx,
@@ -44,21 +53,20 @@ export default (md) => {
     env,
     _self,
   ) => {
-    const name = path.basename(env.id).replace(/\.md$/, "")
-    const renderer = new TOCRenderer(name)
+    const renderer = new TOCRenderer()
     for (let idx = 0; idx < tokens.length; idx++) {
       const token = tokens[idx]
 
       if (token.type !== "heading_open") {
         continue
       }
-      let level = Number(token.tag.substr(1))
+      const level = Number(token.tag.slice(1))
       if (level > 3) {
         continue
       }
       // Aggregate the next token children text.
-      const title = tokens[idx + 1].children
-        .filter(
+      const title = tokens[idx + 1]
+        .children!.filter(
           (token) =>
             token.type === "text" ||
             token.type === "emoji" ||
@@ -66,11 +74,11 @@ export default (md) => {
         )
         .reduce((acc, t) => acc + t.content, "")
 
-      let slug = token.attrGet("id")
+      const slug = token.attrGet("id")!
       renderer.addMenu(level, slug, title)
     }
 
-    const fileInfo = {}
+    const fileInfo: { timestamp?: number; lastUpdated?: string } = {}
     const timestamp = getGitLastUpdatedTimestamp(env.id)
     if (timestamp) {
       fileInfo.timestamp = timestamp
@@ -85,7 +93,7 @@ export default (md) => {
 }
 
 /** Get last updated timestamp */
-function getGitLastUpdatedTimestamp(filePath) {
+function getGitLastUpdatedTimestamp(filePath: string) {
   let lastUpdated
   try {
     lastUpdated =
diff --git a/docs-svelte-kit/tools/markdown-it-replace-link.mjs b/docs-svelte-kit/tools/markdown-it-replace-link.mts
similarity index 70%
rename from docs-svelte-kit/tools/markdown-it-replace-link.mjs
rename to docs-svelte-kit/tools/markdown-it-replace-link.mts
index a1c612b43..c4d8ebf01 100644
--- a/docs-svelte-kit/tools/markdown-it-replace-link.mjs
+++ b/docs-svelte-kit/tools/markdown-it-replace-link.mts
@@ -1,17 +1,17 @@
-// eslint-disable-next-line eslint-comments/disable-enable-pair -- ignore
-/* eslint-disable camelcase -- ignore */
 import path from "path"
+import type Md from "markdown-it"
+import type Token from "markdown-it/lib/token"
 
-export default (md, options = {}) => {
+export default (md: Md, options: { baseUrl: string; root: string }): void => {
   const base = options.baseUrl
   const root = path.resolve(options.root)
 
   /** Normalize href */
-  function normalizeHref(curr, href) {
+  function normalizeHref(curr: string, href: string) {
     let absolutePath
     let hash = ""
     if (/\.md(?:#.*)?$/.test(href)) {
-      hash = /\.md(#.*)?$/.exec(href)[1] || ""
+      hash = /\.md(#.*)?$/.exec(href)![1] || ""
       absolutePath = path.join(
         path.dirname(curr),
         hash ? href.slice(0, -hash.length) : href,
@@ -31,23 +31,23 @@ export default (md, options = {}) => {
     const token = tokens[idx]
     const hrefIndex = token.attrIndex("href")
     if (hrefIndex >= 0) {
-      const link = token.attrs[hrefIndex]
+      const link = token.attrs![hrefIndex]
       const href = link[1]
       if (/^https?:/.test(href)) {
         const proxyToken = {
           ...token,
-          attrs: [...token.attrs, ["target", "_blank"]],
-        }
+          attrs: [...token.attrs!, ["target", "_blank"]],
+        } as Token
         return self.renderToken([proxyToken], 0, options)
       } else if (/\.md(?:#.*)?$/.test(href) || /^#.*$/.test(href)) {
         const proxyToken = {
           ...token,
           attrs: [
-            ...token.attrs.slice(0, hrefIndex - 1),
+            ...token.attrs!.slice(0, hrefIndex - 1),
             [link[0], normalizeHref(env.id, href)],
-            ...token.attrs.slice(hrefIndex + 1),
+            ...token.attrs!.slice(hrefIndex + 1),
           ],
-        }
+        } as Token
         return self.renderToken([proxyToken], 0, options)
       }
     }
diff --git a/docs-svelte-kit/tools/markdown-it-title.mjs b/docs-svelte-kit/tools/markdown-it-title.mts
similarity index 80%
rename from docs-svelte-kit/tools/markdown-it-title.mjs
rename to docs-svelte-kit/tools/markdown-it-title.mts
index 25bda4644..73b9ccac5 100644
--- a/docs-svelte-kit/tools/markdown-it-title.mjs
+++ b/docs-svelte-kit/tools/markdown-it-title.mts
@@ -1,20 +1,21 @@
+import type Md from "markdown-it"
 /**
  * @param {import('markdown-it')} md
  */
-export default (md) => {
+export default (md: Md): void => {
   const headingOpen = md.renderer.rules.heading_open
-  // eslint-disable-next-line camelcase -- ignore
+
   md.renderer.rules.heading_open = (tokens, idx, options, env, self) => {
     const head = headingOpen
       ? headingOpen(tokens, idx, options, env, self)
       : self.renderToken(tokens, idx, options)
     const token = tokens[idx]
-    let level = Number(token.tag.substr(1))
+    const level = Number(token.tag.substr(1))
     if (level > 1) {
       return head
     }
-    const title = tokens[idx + 1].children
-      .filter(
+    const title = tokens[idx + 1]
+      .children!.filter(
         (token) =>
           token.type === "text" ||
           token.type === "emoji" ||
diff --git a/docs-svelte-kit/tools/vite-plugin-svelte-md-option.mjs b/docs-svelte-kit/tools/vite-plugin-svelte-md-option.mts
similarity index 91%
rename from docs-svelte-kit/tools/vite-plugin-svelte-md-option.mjs
rename to docs-svelte-kit/tools/vite-plugin-svelte-md-option.mts
index 1d1a6c4ed..af9ff3fca 100644
--- a/docs-svelte-kit/tools/vite-plugin-svelte-md-option.mjs
+++ b/docs-svelte-kit/tools/vite-plugin-svelte-md-option.mts
@@ -8,8 +8,9 @@ import titlePlugin from "./markdown-it-title.mjs"
 import markdownPlugin from "./markdown-it-markdown.mjs"
 import containerPluginOption from "./markdown-it-container-option.mjs"
 import slugify from "@sindresorhus/slugify"
+import type { Options } from "vite-plugin-svelte-md"
 
-export default (options = {}) => ({
+export default (options: { baseUrl: string; root: string }): Options => ({
   wrapperClasses: [],
   markdownItOptions: {
     highlight,
diff --git a/package.json b/package.json
index 90d15a39c..f8f60c441 100644
--- a/package.json
+++ b/package.json
@@ -43,7 +43,7 @@
     "prepublishOnly": "yarn clean && yarn build",
     "pretest:base": "cross-env DEBUG=eslint-plugin-svelte*",
     "preversion": "yarn test && git add .",
-    "svelte-kit": "node --experimental-loader ./svelte-kit-import-hook.mjs node_modules/vite/bin/vite.js --config vite.config.mjs",
+    "svelte-kit": "node --experimental-loader ./svelte-kit-import-hook.mjs node_modules/vite/bin/vite.js",
     "test": "yarn mocha \"tests/src/**/*.ts\" --reporter dot --timeout 60000",
     "ts": "node -r esbuild-register",
     "update": "yarn ts ./tools/update.ts && yarn format-for-gen-file",
@@ -74,19 +74,25 @@
     "@babel/plugin-proposal-function-bind": "^7.16.7",
     "@babel/types": "^7.16.0",
     "@fontsource/fira-mono": "^4.5.0",
-    "@ota-meshi/eslint-plugin": "^0.11.0",
+    "@ota-meshi/eslint-plugin": "^0.11.3",
     "@sindresorhus/slugify": "^2.1.0",
     "@sveltejs/adapter-static": "^1.0.0-next.26",
     "@sveltejs/kit": "^1.0.0-next.360",
     "@types/babel__core": "^7.1.19",
+    "@types/cross-spawn": "^6.0.2",
+    "@types/escape-html": "^1.0.2",
     "@types/eslint": "^8.0.0",
     "@types/eslint-scope": "^3.7.0",
     "@types/eslint-visitor-keys": "^1.0.0",
     "@types/estree": "^0.0.52",
     "@types/less": "^3.0.3",
+    "@types/markdown-it": "^12.2.3",
+    "@types/markdown-it-container": "^2.0.5",
+    "@types/markdown-it-emoji": "^2.0.2",
     "@types/mocha": "^9.0.0",
     "@types/node": "^16.0.0",
     "@types/postcss-safe-parser": "^5.0.1",
+    "@types/prismjs": "^1.26.0",
     "@types/stylus": "^0.48.38",
     "@typescript-eslint/eslint-plugin": "^5.4.0",
     "@typescript-eslint/parser": "^5.4.1-0",
@@ -119,7 +125,6 @@
     "mocha": "^10.0.0",
     "nyc": "^15.1.0",
     "pako": "^2.0.3",
-    "pirates": "^4.0.1",
     "postcss-nested": "^5.0.6",
     "prettier": "^2.2.1",
     "prettier-plugin-pkg": "^0.16.0",
@@ -134,8 +139,8 @@
     "svelte": "^3.46.1",
     "svelte-adapter-ghpages": "0.0.2",
     "typescript": "^4.5.2",
-    "vite": "^2.9.13",
-    "vite-plugin-svelte-md": "^0.1.3"
+    "vite": "^3.0.0-0",
+    "vite-plugin-svelte-md": "^0.1.5"
   },
   "publishConfig": {
     "access": "public"
diff --git a/svelte-kit-import-hook.mjs b/svelte-kit-import-hook.mjs
index 3b0256a22..5fee66968 100644
--- a/svelte-kit-import-hook.mjs
+++ b/svelte-kit-import-hook.mjs
@@ -2,25 +2,22 @@
 import babelCore from "@babel/core"
 import * as t from "@babel/types"
 
-import pirates from "pirates"
-
-pirates.addHook(transform, {
-  exts: [".js", ".mjs"],
-})
-
 /** transform code */
-function transform(code, _filename) {
-  if (code.includes("import(")) {
+function transform(code, filename) {
+  if (
+    filename.includes("/@sveltejs/kit/") &&
+    code.includes("svelte.config.js")
+  ) {
     let transformed = false
     const newCode = babelCore.transformSync(code, {
       babelrc: false,
       plugins: [
         {
           visitor: {
-            CallExpression(path) {
-              const callee = path.get("callee")
-              if (callee.type === "Import") {
-                callee.replaceWith(t.identifier("$$$import"))
+            StringLiteral(path) {
+              if (path.node.value === "svelte.config.js") {
+                // The configuration file loads `svelte.config.mjs`.
+                path.replaceWith(t.stringLiteral("svelte.config.mjs"))
                 transformed = true
               }
             },
@@ -31,25 +28,7 @@ function transform(code, _filename) {
     if (!transformed) {
       return code
     }
-    return `${newCode.code}
-async function $$$import(module, ...args) {
-  const m = await import(module)
-  return ________adjustModule(m)
-}
-function ________adjustModule(m) {
-  const keys = Object.keys(m);
-  if(m.default && keys.length === 1 && keys[0] === 'default' && typeof m.default === 'object') {
-    const result = {
-      default: ________adjustModule(m.default)
-    }
-    for (const key of Object.keys(m.default)) {
-      result[key] = m.default[key]
-    }
-    return result
-  }
-  return m
-}
-`
+    return `${newCode.code}`
   }
 
   return code
@@ -70,7 +49,7 @@ export async function load(url, context, defaultLoad) {
   const result = await defaultLoad(url, context, defaultLoad)
   return {
     format: result.format,
-    source: transform(`${result.source}`),
+    source: transform(`${result.source}`, url),
   }
 }
 
@@ -90,6 +69,6 @@ export async function transformSource(source, context, defaultTransformSource) {
     defaultTransformSource,
   )
   return {
-    source: transform(`${result.source}`),
+    source: transform(`${result.source}`, context.url),
   }
 }
diff --git a/svelte.config.js b/svelte.config.js
deleted file mode 100644
index 73c8688bc..000000000
--- a/svelte.config.js
+++ /dev/null
@@ -1,95 +0,0 @@
-"use strict"
-
-/* !! This project can't be ESM yet, so hack it to get sveltekit to work. !! */
-const esbuild = require("esbuild")
-const path = require("path")
-const babelCore = require("@babel/core")
-const pirates = require("pirates")
-
-/* -- Build config -- */
-esbuild.buildSync({
-  entryPoints: [require.resolve("./svelte.config.esm.mjs")],
-  outfile: path.join(__dirname, "./svelte.config-dist.js"),
-  format: "cjs",
-  bundle: true,
-  external: [
-    "path",
-    "cross-spawn",
-    "prismjs",
-    "os",
-    "fs",
-    "stream",
-    "zlib",
-    "util",
-    "./docs-svelte-kit/build-system/build.js",
-  ],
-})
-
-/* -- transpile -- */
-const { register } = require("esbuild-register/dist/node")
-register({
-  format: "cjs",
-  extensions: [".js", ".mjs", ".cjs", ".ts"],
-})
-
-/* -- transform '@sveltejs/kit/ssr' path -- */
-pirates.addHook(transformImportSsr, {
-  exts: [".js", ".mjs"],
-})
-
-/** transform '@sveltejs/kit/ssr' path */
-function transformImportSsr(code, _filename) {
-  if (code.includes("@sveltejs/kit/ssr")) {
-    const resolvedPath = require.resolve(
-      "./node_modules/@sveltejs/kit/dist/ssr",
-    )
-    let transformed = false
-    const newCode = babelCore.transformSync(code, {
-      babelrc: false,
-      plugins: [
-        {
-          visitor: {
-            CallExpression(path) {
-              const callee = path.get("callee")
-              if (
-                callee.type !== "Identifier" ||
-                callee.node.name !== "require"
-              ) {
-                return
-              }
-              const args = path.get("arguments")
-              if (args.length !== 1) {
-                return
-              }
-              const arg = args[0]
-              if (
-                arg.type === "StringLiteral" &&
-                arg.node.value === "@sveltejs/kit/ssr"
-              ) {
-                arg.node.value = resolvedPath
-                transformed = true
-              }
-            },
-            ImportDeclaration(path) {
-              if (path.node.source.value === "@sveltejs/kit/ssr") {
-                path.node.source.value = resolvedPath
-                transformed = true
-              }
-            },
-          },
-        },
-      ],
-    })
-    if (!transformed) {
-      return code
-    }
-    return `${newCode.code}`
-  }
-
-  return code
-}
-
-/* eslint node/no-missing-require: 0 -- ignore */
-const config = require("./svelte.config-dist.js").default
-
-module.exports = config
diff --git a/svelte.config.esm.mjs b/svelte.config.mjs
similarity index 65%
rename from svelte.config.esm.mjs
rename to svelte.config.mjs
index 0a27a6952..1bc0e851a 100644
--- a/svelte.config.esm.mjs
+++ b/svelte.config.mjs
@@ -1,14 +1,18 @@
-/* global __dirname, URL -- __dirname, URL */
 import ghpagesAdapter from "svelte-adapter-ghpages"
 import path from "path"
+import fs from "fs"
 
-const dirname =
-  typeof __dirname !== "undefined"
-    ? __dirname
-    : (() => {
-        const metaUrl = Function(`return import.meta.url`)()
-        return path.dirname(new URL(metaUrl).pathname)
-      })()
+const dirname = path.dirname(new URL(import.meta.url).pathname)
+
+// This project can't be ESM yet, so hack it to get svelte-kit to work.
+// A hack that treats files in the `.svelte-kit` directory as ESM.
+if (!fs.existsSync(path.join(dirname, ".svelte-kit"))) {
+  fs.mkdirSync(path.join(dirname, ".svelte-kit"))
+}
+fs.writeFileSync(
+  path.join(dirname, ".svelte-kit/package.json"),
+  JSON.stringify({ type: "module" }),
+)
 
 /** @type {import('@sveltejs/kit').Config} */
 const config = {
diff --git a/tsconfig.build.json b/tsconfig.build.json
index 31b62dbf8..542d743fb 100644
--- a/tsconfig.build.json
+++ b/tsconfig.build.json
@@ -1,6 +1,12 @@
 {
   "extends": "./tsconfig.json",
-  "exclude": ["tests/**/*", "tools/**/*", "typings/**/*"],
+  "exclude": [
+    "tests/**/*",
+    "tools/**/*",
+    "typings/**/*",
+    "vite.config.mts",
+    "docs-svelte-kit/**/*.mts"
+  ],
   "compilerOptions": {
     "removeComments": true /* Do not emit comments to output. */
   }
diff --git a/tsconfig.json b/tsconfig.json
index 9c5f25268..f498baa9c 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -27,7 +27,9 @@
     "src/**/*",
     "tests/src/**/*",
     "tests/utils/**/*",
-    "tools/**/*"
+    "tools/**/*",
+    "vite.config.mts",
+    "docs-svelte-kit/**/*.mts"
     // "typings/**/*"
   ],
   "exclude": ["lib/**/*", "tests/fixtures/**/*"]
diff --git a/vite.config.mjs b/vite.config.mts
similarity index 82%
rename from vite.config.mjs
rename to vite.config.mts
index a9c730e15..9e2c669f5 100644
--- a/vite.config.mjs
+++ b/vite.config.mts
@@ -1,15 +1,21 @@
-/* global URL -- URL */
+// @ts-expect-error -- Missing type information
 import { sveltekit } from "@sveltejs/kit/vite"
 import path from "path"
 import svelteMd from "vite-plugin-svelte-md"
 import svelteMdOption from "./docs-svelte-kit/tools/vite-plugin-svelte-md-option.mjs"
 
-import "./docs-svelte-kit/build-system/build.js"
+import "./docs-svelte-kit/build-system/build.mts"
+import type { UserConfig } from "vite"
 
-const dirname = path.dirname(new URL(import.meta.url).pathname)
+const dirname = path.dirname(
+  new URL(
+    // @ts-expect-error -- Cannot change `module` option
+    import.meta.url,
+  ).pathname,
+)
 
 /** @type {import('vite').UserConfig} */
-const config = {
+const config: UserConfig = {
   plugins: [
     svelteMd(
       svelteMdOption({