diff --git a/eslint.config.mjs b/eslint.config.mjs
index 4255d5f..1389b9e 100644
--- a/eslint.config.mjs
+++ b/eslint.config.mjs
@@ -26,9 +26,6 @@ export default [
     ]
   },
   {
-    "languageOptions": {
-      "sourceType": "commonjs"
-    },
     "linterOptions": {
       "reportUnusedDisableDirectives": true
     },
@@ -68,10 +65,20 @@ export default [
   },
   {
     "files": [
-      "**/*.mjs"
+      "**/*-formatter-*.js",
+      "webworker/*.js"
+    ],
+    "ignores": [
+      "webworker/fs-virtual.js"
     ],
     "languageOptions": {
-      "sourceType": "module"
+      "sourceType": "commonjs",
+      "globals": {
+        "__dirname": "readonly",
+        "__filename": "readonly",
+        "module": "readonly",
+        "require": "readonly"
+      }
     }
   }
 ];
diff --git a/export-markdownlint-helpers.js b/export-markdownlint-helpers.js
index 90d31e2..6598099 100644
--- a/export-markdownlint-helpers.js
+++ b/export-markdownlint-helpers.js
@@ -1,4 +1,3 @@
 // @ts-check
 
-import helpers from "markdownlint/helpers";
-export default helpers;
+export { default } from "markdownlint/helpers";
diff --git a/export-markdownlint.js b/export-markdownlint.js
index a1e0f6b..d14558b 100644
--- a/export-markdownlint.js
+++ b/export-markdownlint.js
@@ -1,4 +1,3 @@
 // @ts-check
 
-import markdownlint from "markdownlint";
-export default markdownlint;
+export { default } from "markdownlint";
diff --git a/markdownlint-cli2.js b/markdownlint-cli2.js
index 19e57d4..a4b7ba7 100755
--- a/markdownlint-cli2.js
+++ b/markdownlint-cli2.js
@@ -4,7 +4,7 @@
 
 // Requires
 import fsx from "node:fs";
-import { createRequire } from 'node:module';
+import { createRequire } from "node:module";
 const dynamicRequire = createRequire(import.meta.url);
 import os from "node:os";
 import pathDefault from "node:path";
@@ -211,12 +211,12 @@ const readOptionsOrConfig = async (configPath, fs, noRequire) => {
 };
 
 // Filter a list of files to ignore by glob
-const removeIgnoredFiles = (dir, files, ignores) => {
-  return micromatch(
+const removeIgnoredFiles = (dir, files, ignores) => (
+  micromatch(
     files.map((file) => pathPosix.relative(dir, file)),
     ignores
-  ).map((file) => pathPosix.join(dir, file));
-};
+  ).map((file) => pathPosix.join(dir, file))
+);
 
 // Process/normalize command-line arguments and return glob patterns
 const processArgv = (argv) => {
@@ -886,6 +886,7 @@ const outputSummary = async (
     const dirs = [ dir, ...modulePaths ];
     const formattersAndParams = outputFormatters
       ? await importOrRequireIdsAndParams(dirs, outputFormatters, noRequire)
+      // eslint-disable-next-line unicorn/no-await-expression-member
       : [ [ (await import("markdownlint-cli2-formatter-default")).default ] ];
     await Promise.all(formattersAndParams.map((formatterAndParams) => {
       const [ formatter, ...formatterParams ] = formatterAndParams;
diff --git a/package.json b/package.json
index 2834a7d..a3347ba 100644
--- a/package.json
+++ b/package.json
@@ -95,7 +95,6 @@
     "eslint-plugin-jsdoc": "50.5.0",
     "eslint-plugin-n": "17.13.2",
     "eslint-plugin-unicorn": "56.0.0",
-    "nano-spawn": "0.2.0",
     "markdown-it-emoji": "3.0.0",
     "markdown-it-for-inline": "2.0.1",
     "markdownlint-cli2-formatter-codequality": "0.0.5",
@@ -106,6 +105,7 @@
     "markdownlint-cli2-formatter-summarize": "0.0.7",
     "markdownlint-cli2-formatter-template": "0.0.2",
     "markdownlint-rule-extended-ascii": "0.1.0",
+    "nano-spawn": "0.2.0",
     "npm-run-all": "4.1.5"
   },
   "keywords": [
diff --git a/test/fs-mock.js b/test/fs-mock.js
index 7f9a0e5..655b5d8 100644
--- a/test/fs-mock.js
+++ b/test/fs-mock.js
@@ -3,9 +3,9 @@
 import fs from "node:fs";
 import nodePath from "node:path";
 
-const mapPath = (base, mockPath) => {
-  return nodePath.resolve(base, nodePath.relative("/mock", mockPath));
-};
+const mapPath = (base, mockPath) => (
+  nodePath.resolve(base, nodePath.relative("/mock", mockPath))
+);
 
 class fsMock {
   constructor(base, symbolicLinks) {
diff --git a/test/import-with-type-json.mjs b/test/import-with-type-json.mjs
index 7b2cc92..60521e2 100644
--- a/test/import-with-type-json.mjs
+++ b/test/import-with-type-json.mjs
@@ -4,4 +4,9 @@ import fs from "node:fs/promises";
 import path from "node:path";
 
 // Avoids "ExperimentalWarning: Importing JSON modules is an experimental feature and might change at any time"
-export default async (file) => JSON.parse(await fs.readFile(path.resolve(import.meta.dirname, file), "utf8"));
+const importWithTypeJson = async (file) => (
+  // @ts-ignore
+  JSON.parse(await fs.readFile(path.resolve(import.meta.dirname, file)))
+);
+
+export default importWithTypeJson;
diff --git a/test/markdownlint-cli2-test-exports.js b/test/markdownlint-cli2-test-exports.js
index 84f948f..74b7bbd 100644
--- a/test/markdownlint-cli2-test-exports.js
+++ b/test/markdownlint-cli2-test-exports.js
@@ -4,9 +4,6 @@ import test from "ava";
 import importWithTypeJson from "./import-with-type-json.mjs";
 const packageJson = await importWithTypeJson("../package.json");
 
-import { createRequire } from "node:module";
-const require = createRequire(import.meta.url);
-
 const exportMappings = new Map([
   [ ".", "../markdownlint-cli2.js" ],
   [ "./markdownlint", "markdownlint" ],
@@ -23,9 +20,11 @@ test("exportMappings", (t) => {
   );
 });
 
+const commonJsRe = /.js$/u;
+
 for (const [ exportName, exportPath ] of exportMappings) {
   test(exportName, async (t) => {
-    const commonJs = !/.js$/.test(exportPath);
+    const commonJs = !commonJsRe.test(exportPath);
     const importExportName = await import(exportName.replace(/^\./u, packageJson.name));
     const importExportPath = await import(exportPath);
     t.is(
diff --git a/test/resolve-and-require-test.js b/test/resolve-and-require-test.js
index b5f0bea..93f5019 100644
--- a/test/resolve-and-require-test.js
+++ b/test/resolve-and-require-test.js
@@ -7,8 +7,6 @@ import resolveAndRequire from "../resolve-and-require.js";
 import { createRequire } from "node:module";
 const require = createRequire(import.meta.url);
 
-/* eslint-disable n/no-missing-require */
-
 test("built-in module", (t) => {
   t.plan(1);
   t.deepEqual(