diff --git a/test/customRules-pre-imported/.markdownlint-cli2.cjs b/test/customRules-pre-imported/.markdownlint-cli2.cjs
index 98fa5da8..5ba88bee 100644
--- a/test/customRules-pre-imported/.markdownlint-cli2.cjs
+++ b/test/customRules-pre-imported/.markdownlint-cli2.cjs
@@ -2,7 +2,7 @@
 
 "use strict";
 
-const anyBlockquote = require("./rules/any-blockquote.js");
+const anyBlockquote = require("./rules/any-blockquote.cjs");
 
 module.exports = {
   "customRules": [
diff --git a/test/customRules-pre-imported/rules/any-blockquote.js b/test/customRules-pre-imported/rules/any-blockquote.cjs
similarity index 100%
rename from test/customRules-pre-imported/rules/any-blockquote.js
rename to test/customRules-pre-imported/rules/any-blockquote.cjs
diff --git a/test/customRules-throws/.markdownlint-cli2.jsonc b/test/customRules-throws/.markdownlint-cli2.jsonc
index 59e833f9..5d41a132 100644
--- a/test/customRules-throws/.markdownlint-cli2.jsonc
+++ b/test/customRules-throws/.markdownlint-cli2.jsonc
@@ -1,5 +1,5 @@
 {
   "customRules": [
-    "./rules/throws.js"
+    "./rules/throws.cjs"
   ]
 }
diff --git a/test/customRules-throws/rules/throws.js b/test/customRules-throws/rules/throws.cjs
similarity index 100%
rename from test/customRules-throws/rules/throws.js
rename to test/customRules-throws/rules/throws.cjs
diff --git a/test/customRules/.markdownlint-cli2.jsonc b/test/customRules/.markdownlint-cli2.jsonc
index 1350bd58..599aee08 100644
--- a/test/customRules/.markdownlint-cli2.jsonc
+++ b/test/customRules/.markdownlint-cli2.jsonc
@@ -1,8 +1,8 @@
 {
   "customRules": [
-    "./rules/any-blockquote.js",
-    "./rules/every-n-lines.js",
-    "./rules/first-line.js"
+    "./rules/any-blockquote.cjs",
+    "./rules/every-n-lines.cjs",
+    "./rules/first-line.cjs"
   ],
   "config": {
     "every-n-lines": {
diff --git a/test/customRules/dir/subdir/.markdownlint-cli2.jsonc b/test/customRules/dir/subdir/.markdownlint-cli2.jsonc
index ab641367..66c3cb4b 100644
--- a/test/customRules/dir/subdir/.markdownlint-cli2.jsonc
+++ b/test/customRules/dir/subdir/.markdownlint-cli2.jsonc
@@ -1,6 +1,6 @@
 {
   "customRules": [
-    "../../rules/first-line.js",
+    "../../rules/first-line.cjs",
     "../../node_modules/markdownlint-rule-sample-commonjs",
     "../../node_modules/markdownlint-rule-sample-module/sample-rule.mjs",
     "markdownlint-rule-extended-ascii"
diff --git a/test/customRules/dir3/.markdownlint-cli2.jsonc b/test/customRules/dir3/.markdownlint-cli2.jsonc
index 0fed617e..e9a71c6c 100644
--- a/test/customRules/dir3/.markdownlint-cli2.jsonc
+++ b/test/customRules/dir3/.markdownlint-cli2.jsonc
@@ -1,6 +1,6 @@
 {
   "customRules": [
-    "../rules/all-rules",
+    "../rules/all-rules.cjs",
     "../node_modules/markdownlint-rule-sample-commonjs",
     "../node_modules/markdownlint-rule-sample-module/sample-rule.mjs"
   ]
diff --git a/test/customRules/rules/all-rules.cjs b/test/customRules/rules/all-rules.cjs
new file mode 100644
index 00000000..b333a173
--- /dev/null
+++ b/test/customRules/rules/all-rules.cjs
@@ -0,0 +1,10 @@
+// @ts-check
+
+"use strict";
+
+module.exports = [
+  require("./any-blockquote.cjs"),
+  require("./every-n-lines.cjs"),
+  require("./first-line.cjs"),
+  require("./second-line.cjs")
+];
diff --git a/test/customRules/rules/all-rules.js b/test/customRules/rules/all-rules.js
deleted file mode 100644
index 32817133..00000000
--- a/test/customRules/rules/all-rules.js
+++ /dev/null
@@ -1,10 +0,0 @@
-// @ts-check
-
-"use strict";
-
-module.exports = [
-  require("./any-blockquote"),
-  require("./every-n-lines"),
-  require("./first-line"),
-  require("./second-line")
-];
diff --git a/test/customRules/rules/any-blockquote.js b/test/customRules/rules/any-blockquote.cjs
similarity index 100%
rename from test/customRules/rules/any-blockquote.js
rename to test/customRules/rules/any-blockquote.cjs
diff --git a/test/customRules/rules/every-n-lines.js b/test/customRules/rules/every-n-lines.cjs
similarity index 100%
rename from test/customRules/rules/every-n-lines.js
rename to test/customRules/rules/every-n-lines.cjs
diff --git a/test/customRules/rules/second-line.js b/test/customRules/rules/second-line.cjs
similarity index 100%
rename from test/customRules/rules/second-line.js
rename to test/customRules/rules/second-line.cjs
diff --git a/test/import-with-type-json.mjs b/test/import-with-type-json.mjs
new file mode 100644
index 00000000..7b2cc924
--- /dev/null
+++ b/test/import-with-type-json.mjs
@@ -0,0 +1,7 @@
+// @ts-check
+
+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"));
diff --git a/test/markdownlint-cli2-test-cases.js b/test/markdownlint-cli2-test-cases.js
index 11fdfad6..b4c34534 100644
--- a/test/markdownlint-cli2-test-cases.js
+++ b/test/markdownlint-cli2-test-cases.js
@@ -1,11 +1,9 @@
 // @ts-check
 
-"use strict";
-
-const fs = require("node:fs").promises;
-const os = require("node:os");
-const path = require("node:path");
-const test = require("ava").default;
+import fs from "node:fs/promises";
+import os from "node:os";
+import path from "node:path";
+import test from "ava";
 
 const noop = () => null;
 const empty = () => "";
@@ -13,7 +11,7 @@ const sanitize = (str) => str.
   replace(/\r/gu, "").
   replace(/\bv\d+\.\d+\.\d+\b/gu, "vX.Y.Z").
   replace(/ :.+[/\\]sentinel/gu, " :[PATH]");
-const sameFileSystem = (path.relative(os.homedir(), __dirname) !== __dirname);
+const sameFileSystem = (path.relative(os.homedir(), import.meta.dirname) !== import.meta.dirname);
 const isModule = (file) => file.endsWith(".cjs") || file.endsWith(".mjs");
 
 const testCases = ({
@@ -57,7 +55,7 @@ const testCases = ({
     }
     test(`${name} (${host})`, (t) => {
       t.plan(3);
-      const directory = path.join(__dirname, cwd || name);
+      const directory = path.join(import.meta.dirname, cwd || name);
       return ((pre || noop)(name, shadow) || Promise.resolve()).
         then(invoke(directory, args, noRequire, env, script)).
         then((result) => Promise.all([
@@ -143,13 +141,13 @@ const testCases = ({
 
   const copyDirectory = (dir, alt) => import("cpy").then((cpy) => (
     cpy.default(
-      path.join(__dirname, (alt || dir), "**"),
-      path.join(__dirname, directoryName(dir))
+      path.join(import.meta.dirname, (alt || dir), "**"),
+      path.join(import.meta.dirname, directoryName(dir))
     )
   ));
 
   const deleteDirectory = (dir) => import("del").then((del) => (
-    del.deleteAsync(path.join(__dirname, directoryName(dir)))
+    del.deleteAsync(path.join(import.meta.dirname, directoryName(dir)))
   ));
 
   testCase({
@@ -588,7 +586,7 @@ const testCases = ({
   });
 
   const literalFilesAbsoluteFile = absolute(
-    path.join(__dirname, "literal-files"),
+    path.join(import.meta.dirname, "literal-files"),
     "sentinel/dir(1)/(view)me.md"
   ).
     split(path.sep).
@@ -670,7 +668,7 @@ const testCases = ({
       "name": `config-files-${configFile}-absolute-arg`,
       "args": [
         "--config",
-        path.join(__dirname, "config-files", `cfg/${configFile}`),
+        path.join(import.meta.dirname, "config-files", `cfg/${configFile}`),
         "**/*.md"
       ],
       "exitCode": 1,
@@ -1161,4 +1159,4 @@ const testCases = ({
 
 };
 
-module.exports = testCases;
+export default testCases;
diff --git a/test/markdownlint-cli2-test-exec.js b/test/markdownlint-cli2-test-exec.js
index 394262f5..c1671ba3 100644
--- a/test/markdownlint-cli2-test-exec.js
+++ b/test/markdownlint-cli2-test-exec.js
@@ -1,14 +1,12 @@
 // @ts-check
 
-"use strict";
-
-const fs = require("node:fs/promises");
-const path = require("node:path");
-const test = require("ava").default;
-const testCases = require("./markdownlint-cli2-test-cases");
+import fs from "node:fs/promises";
+import path from "node:path";
+import test from "ava";
+import testCases from "./markdownlint-cli2-test-cases.js";
 
 const absolute = (rootDir, file) => path.join(rootDir, file);
-const repositoryPath = (name) => path.join(__dirname, "..", name);
+const repositoryPath = (name) => path.join(import.meta.dirname, "..", name);
 
 const invoke = (directory, args, noRequire, env, script) => async () => {
   await fs.access(directory);
@@ -160,7 +158,7 @@ test("- parameter uses base directory configuration", (t) => {
   return invokeStdin(
     [ "-" ],
     invalidInput,
-    path.join(__dirname, "stdin")
+    path.join(import.meta.dirname, "stdin")
   ).
     then(() => t.fail()).
     catch((error) => {
@@ -174,7 +172,7 @@ test("- parameter not treated as stdin in configuration file globs", (t) => {
   return invokeStdin(
     [],
     invalidInput,
-    path.join(__dirname, "stdin-globs")
+    path.join(import.meta.dirname, "stdin-globs")
   ).
     then(() => t.pass()).
     catch(() => t.fail());
diff --git a/test/markdownlint-cli2-test-exports.js b/test/markdownlint-cli2-test-exports.js
index 7fd6b0bc..84f948f6 100644
--- a/test/markdownlint-cli2-test-exports.js
+++ b/test/markdownlint-cli2-test-exports.js
@@ -1,7 +1,8 @@
 // @ts-check
 
 import test from "ava";
-import packageJson from "../package.json" with { type: "json" };
+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);
diff --git a/test/markdownlint-cli2-test-fs.js b/test/markdownlint-cli2-test-fs.js
index d2b703af..35bc42eb 100644
--- a/test/markdownlint-cli2-test-fs.js
+++ b/test/markdownlint-cli2-test-fs.js
@@ -1,11 +1,9 @@
 // @ts-check
 
-"use strict";
-
-const path = require("node:path");
-const { "main": markdownlintCli2 } = require("../markdownlint-cli2.js");
-const testCases = require("./markdownlint-cli2-test-cases");
-const FsMock = require("./fs-mock");
+import path from "node:path";
+import { "main" as markdownlintCli2 } from "../markdownlint-cli2.js";
+import testCases from "./markdownlint-cli2-test-cases.js";
+import FsMock from "./fs-mock.js";
 const mockDirectory = "/mock";
 
 const linesEndingWithNewLine =
diff --git a/test/markdownlint-cli2-test-main.js b/test/markdownlint-cli2-test-main.js
index 80e61ca7..cbe93e84 100644
--- a/test/markdownlint-cli2-test-main.js
+++ b/test/markdownlint-cli2-test-main.js
@@ -1,10 +1,8 @@
 // @ts-check
 
-"use strict";
-
-const path = require("node:path");
-const { "main": markdownlintCli2 } = require("../markdownlint-cli2.js");
-const testCases = require("./markdownlint-cli2-test-cases");
+import path from "node:path";
+import { "main" as markdownlintCli2 } from "../markdownlint-cli2.js";
+import testCases from "./markdownlint-cli2-test-cases.js";
 
 const linesEndingWithNewLine =
   (lines) => lines.map((line) => `${line}\n`).join("");
diff --git a/test/markdownlint-cli2-test.js b/test/markdownlint-cli2-test.js
index fda92323..bb068e5c 100644
--- a/test/markdownlint-cli2-test.js
+++ b/test/markdownlint-cli2-test.js
@@ -1,14 +1,13 @@
 // @ts-check
 
-"use strict";
-
 import nodeFs from "node:fs";
 import fs from "node:fs/promises";
 import path from "node:path";
 import Ajv from "ajv";
 import test from "ava";
 import { globby } from "globby";
-import packageJson from "../package.json" with { type: "json" };
+import importWithTypeJson from "./import-with-type-json.mjs";
+const packageJson = await importWithTypeJson("../package.json");
 import { "main" as markdownlintCli2 } from "../markdownlint-cli2.js";
 import jsoncParse from "../parsers/jsonc-parse.js";
 import yamlParse from "../parsers/yaml-parse.js";
@@ -17,8 +16,8 @@ import FsVirtual from "../webworker/fs-virtual.js";
 import firstLine from "./customRules/rules/first-line.cjs";
 
 const schemaIdVersionRe = /^.*v(?<version>\d+\.\d+\.\d+).*$/u;
-import markdownlintConfigSchemaDefinition from "../schema/markdownlint-config-schema.json" with { type: "json" };
-import markdownlintCli2ConfigSchemaDefinition from "../schema/markdownlint-cli2-config-schema.json" with { type: "json" };
+const markdownlintConfigSchemaDefinition = await importWithTypeJson("../schema/markdownlint-config-schema.json");
+const markdownlintCli2ConfigSchemaDefinition = await importWithTypeJson("../schema/markdownlint-cli2-config-schema.json");
 
 const outputFormatterLengthIs = (t, length) => (options) => {
   const { results } = options;
diff --git a/test/nested-options-config/config-options-disjoint-empty/dir/dir/.markdownlint-cli2.jsonc b/test/nested-options-config/config-options-disjoint-empty/dir/dir/.markdownlint-cli2.jsonc
index 3b0219dc..9f3778dd 100644
--- a/test/nested-options-config/config-options-disjoint-empty/dir/dir/.markdownlint-cli2.jsonc
+++ b/test/nested-options-config/config-options-disjoint-empty/dir/dir/.markdownlint-cli2.jsonc
@@ -1,5 +1,5 @@
 {
   "customRules": [
-    "../../../first-line.js"
+    "../../../first-line.cjs"
   ]
 }
diff --git a/test/nested-options-config/config-options-disjoint/dir/dir/.markdownlint-cli2.jsonc b/test/nested-options-config/config-options-disjoint/dir/dir/.markdownlint-cli2.jsonc
index 3b0219dc..9f3778dd 100644
--- a/test/nested-options-config/config-options-disjoint/dir/dir/.markdownlint-cli2.jsonc
+++ b/test/nested-options-config/config-options-disjoint/dir/dir/.markdownlint-cli2.jsonc
@@ -1,5 +1,5 @@
 {
   "customRules": [
-    "../../../first-line.js"
+    "../../../first-line.cjs"
   ]
 }
diff --git a/test/nested-options-config/config-options-overlap-empty/dir/dir/.markdownlint-cli2.jsonc b/test/nested-options-config/config-options-overlap-empty/dir/dir/.markdownlint-cli2.jsonc
index 4569433e..c8e78b72 100644
--- a/test/nested-options-config/config-options-overlap-empty/dir/dir/.markdownlint-cli2.jsonc
+++ b/test/nested-options-config/config-options-overlap-empty/dir/dir/.markdownlint-cli2.jsonc
@@ -1,6 +1,6 @@
 {
   "customRules": [
-    "../../../first-line.js"
+    "../../../first-line.cjs"
   ],
   "config": {
     "no-space-in-code": false
diff --git a/test/nested-options-config/config-options-overlap/dir/dir/.markdownlint-cli2.jsonc b/test/nested-options-config/config-options-overlap/dir/dir/.markdownlint-cli2.jsonc
index 4569433e..c8e78b72 100644
--- a/test/nested-options-config/config-options-overlap/dir/dir/.markdownlint-cli2.jsonc
+++ b/test/nested-options-config/config-options-overlap/dir/dir/.markdownlint-cli2.jsonc
@@ -1,6 +1,6 @@
 {
   "customRules": [
-    "../../../first-line.js"
+    "../../../first-line.cjs"
   ],
   "config": {
     "no-space-in-code": false
diff --git a/test/nested-options-config/first-line.js b/test/nested-options-config/first-line.cjs
similarity index 100%
rename from test/nested-options-config/first-line.js
rename to test/nested-options-config/first-line.cjs
diff --git a/test/nested-options-config/options-config-disjoint-empty/.markdownlint-cli2.jsonc b/test/nested-options-config/options-config-disjoint-empty/.markdownlint-cli2.jsonc
index 37174581..07bd66bb 100644
--- a/test/nested-options-config/options-config-disjoint-empty/.markdownlint-cli2.jsonc
+++ b/test/nested-options-config/options-config-disjoint-empty/.markdownlint-cli2.jsonc
@@ -1,5 +1,5 @@
 {
   "customRules": [
-    "../first-line.js"
+    "../first-line.cjs"
   ]
 }
diff --git a/test/nested-options-config/options-config-disjoint/.markdownlint-cli2.jsonc b/test/nested-options-config/options-config-disjoint/.markdownlint-cli2.jsonc
index 37174581..07bd66bb 100644
--- a/test/nested-options-config/options-config-disjoint/.markdownlint-cli2.jsonc
+++ b/test/nested-options-config/options-config-disjoint/.markdownlint-cli2.jsonc
@@ -1,5 +1,5 @@
 {
   "customRules": [
-    "../first-line.js"
+    "../first-line.cjs"
   ]
 }
diff --git a/test/nested-options-config/options-config-overlap-empty/.markdownlint-cli2.jsonc b/test/nested-options-config/options-config-overlap-empty/.markdownlint-cli2.jsonc
index 8c0936d0..ee852567 100644
--- a/test/nested-options-config/options-config-overlap-empty/.markdownlint-cli2.jsonc
+++ b/test/nested-options-config/options-config-overlap-empty/.markdownlint-cli2.jsonc
@@ -1,6 +1,6 @@
 {
   "customRules": [
-    "../first-line.js"
+    "../first-line.cjs"
   ],
   "config": {
     "no-space-in-code": false
diff --git a/test/nested-options-config/options-config-overlap/.markdownlint-cli2.jsonc b/test/nested-options-config/options-config-overlap/.markdownlint-cli2.jsonc
index 8c0936d0..ee852567 100644
--- a/test/nested-options-config/options-config-overlap/.markdownlint-cli2.jsonc
+++ b/test/nested-options-config/options-config-overlap/.markdownlint-cli2.jsonc
@@ -1,6 +1,6 @@
 {
   "customRules": [
-    "../first-line.js"
+    "../first-line.cjs"
   ],
   "config": {
     "no-space-in-code": false