diff --git a/package.json b/package.json
index 80bb6df57a0d..db81f0674cc1 100644
--- a/package.json
+++ b/package.json
@@ -43,9 +43,9 @@
   "scripts": {
     "create-patch": "node tools/create-patch.js",
     "curate": "node tools/prepare-curated.js ed curated && node tools/prepare-packages.js curated packages",
-    "test": "mocha --recursive",
-    "test-css": "mocha --recursive test/css",
-    "test-elements": "mocha --recursive test/elements",
-    "test-idl": "mocha --recursive test/idl"
+    "test": "node --test",
+    "test-css": "node --test \"test/css/*.js\"",
+    "test-elements": "node --test \"test/elements/*.js\"",
+    "test-idl": "node --test \"test/idl/*.js\""
   }
 }
diff --git a/test/cddl/all.js b/test/cddl/all.js
index dfffb06974d9..98e8769e36a4 100644
--- a/test/cddl/all.js
+++ b/test/cddl/all.js
@@ -4,6 +4,7 @@
  * The tests run against the curated view of the extracts.
  */
 
+import { describe, it } from 'node:test';
 import { strict as assert } from 'node:assert';
 import path from 'node:path';
 import { fileURLToPath } from 'node:url';
@@ -19,9 +20,8 @@ function writeAnomalies(report) {
     report.map(anomaly => anomaly.content).join('\n');
 }
 
-describe('The curated view of CDDL extracts', function () {
-  // First run may download micropip and cddlparser packages from the net
-  this.timeout(30000);
+describe('The curated view of CDDL extracts', {timeout: 30000}, function () {
+  // Long timeout as first run may download micropip and cddlparser packages
 
   it('passes Strudy\'s scrutiny', async function () {
     const crawlFile = path.join(curatedFolder, 'index.json');
diff --git a/test/css/all.js b/test/css/all.js
index c7671adc0753..c082949a22ec 100644
--- a/test/css/all.js
+++ b/test/css/all.js
@@ -7,6 +7,7 @@
  * data because that view is a strict subset of the curated view.
  */
 
+import { describe, it, before } from 'node:test';
 import { strict as assert } from 'node:assert';
 import path from 'node:path';
 import { fileURLToPath } from 'node:url';
diff --git a/test/css/package.js b/test/css/package.js
index ff286bb012d2..0fb63b18f0bc 100644
--- a/test/css/package.js
+++ b/test/css/package.js
@@ -1,3 +1,4 @@
+import { describe, it } from 'node:test';
 import { strict as assert } from 'node:assert';
 
 import cssPackage from '../../packages/css/package.json' with { type: 'json' };
diff --git a/test/elements/all.js b/test/elements/all.js
index 7b0b4482abba..da93242537fa 100644
--- a/test/elements/all.js
+++ b/test/elements/all.js
@@ -7,6 +7,7 @@
  * the data because that view is a strict subset of the curated view.
  */
 
+import { describe, it } from 'node:test';
 import { strict as assert } from 'node:assert';
 import path from 'node:path';
 import { fileURLToPath } from 'node:url';
@@ -17,7 +18,6 @@ const curatedFolder = path.join(scriptPath, '..', '..', 'curated', 'elements');
 
 describe('The curated view of elements extracts', function () {
   it('contains valid JSON and expected properties', async function () {
-    this.slow(5000);
 
     const all = await elements.listAll({ folder: curatedFolder });
     assert(Object.keys(all).length > 0);
diff --git a/test/elements/consistency.js b/test/elements/consistency.js
index ed66fea43a33..576a8724c38f 100644
--- a/test/elements/consistency.js
+++ b/test/elements/consistency.js
@@ -6,6 +6,7 @@
  * view because of some missing IDL definition in that view.
  */
 
+import { describe, it, before } from 'node:test';
 import { strict as assert } from 'node:assert';
 import path from 'node:path';
 import { fileURLToPath } from 'node:url';
diff --git a/test/events/all.js b/test/events/all.js
index c04107462b54..53bb97d3955d 100644
--- a/test/events/all.js
+++ b/test/events/all.js
@@ -7,6 +7,7 @@
  * the data because that view is a strict subset of the curated view.
  */
 
+import { describe, it, before } from 'node:test';
 import { strict as assert } from 'node:assert';
 import path from 'node:path';
 import { fileURLToPath } from 'node:url';
@@ -146,4 +147,4 @@ describe('The curated view of events extracts', () => {
   // Dummy test to make sure that "before" function runs and has a place
   // to report runtime errors
   it('contains events', () => {});
-});
\ No newline at end of file
+});
diff --git a/test/idl/all.js b/test/idl/all.js
index c6f23947b381..52f0ba59e6c4 100644
--- a/test/idl/all.js
+++ b/test/idl/all.js
@@ -7,6 +7,7 @@
  * data because that view is a strict subset of the curated view.
  */
 
+import { describe, it } from 'node:test';
 import { strict as assert } from 'node:assert';
 import path from 'node:path';
 import { fileURLToPath } from 'node:url';
@@ -16,7 +17,6 @@ const scriptPath = path.dirname(fileURLToPath(import.meta.url));
 const curatedFolder = path.join(scriptPath, '..', '..', 'curated', 'idl');
 
 describe('The curated view of Web IDL extracts', function () {
-  this.slow(5000);
 
   it('contains valid JSON and expected properties', async function () {
     const files = await idl.listAll({ folder: curatedFolder });
diff --git a/test/idl/consistency.js b/test/idl/consistency.js
index bf9f4c0a2463..68a702d46862 100644
--- a/test/idl/consistency.js
+++ b/test/idl/consistency.js
@@ -10,6 +10,7 @@
  * view because of some missing IDL definition in that view.
  */
 
+import { describe, it } from 'node:test';
 import { strict as assert } from 'node:assert';
 import path from 'node:path';
 import { fileURLToPath } from 'node:url';
@@ -59,4 +60,4 @@ views.forEach(({ name, folder }) => {
       assert.equal(results.length, 0, writeAnomalies(results));
     });
   });
-});
\ No newline at end of file
+});
diff --git a/test/idl/package.js b/test/idl/package.js
index 40794682f9a6..73c666ad21a8 100644
--- a/test/idl/package.js
+++ b/test/idl/package.js
@@ -1,3 +1,4 @@
+import { describe, it } from 'node:test';
 import { strict as assert } from 'node:assert';
 
 import idlPackage from '../../packages/idl/package.json' with { type: 'json' };
diff --git a/test/idl/validate.js b/test/idl/validate.js
index d5dd48f51e23..5e31acde46ed 100644
--- a/test/idl/validate.js
+++ b/test/idl/validate.js
@@ -9,6 +9,7 @@
  * the package view, e.g. due to missing base interfaces.
  */
 
+import { describe, it } from 'node:test';
 import { strict as assert } from 'node:assert';
 import path from 'node:path';
 import { fileURLToPath } from 'node:url';
@@ -20,6 +21,7 @@ const curatedView = {
   name: 'curated',
   folder: path.join(scriptPath, '..', '..', 'curated', 'idl')
 };
+
 const packageView = {
   name: '@webref/idl package',
   folder: path.join(scriptPath, '..', '..', 'packages', 'idl')
@@ -40,44 +42,39 @@ function validate(ast) {
   assert.fail(message);
 }
 
-describe(`The ${curatedView.name} view of Web IDL extracts`, function () {
-  before(async () => {
-    const all = await idl.parseAll(curatedView.folder);
+describe(`The ${curatedView.name} view of Web IDL extracts`, async function () {
+  let all;
+  try {
+    all = await idl.parseAll({folder: curatedView.folder});
+  } catch (err) {
+    it('contains data that can be parsed with webidl2.js', () => {throw err ;});
+  };
 
-    describe(`The ${curatedView.name} view of Web IDL extracts`, function () {
-      for (const [spec, ast] of Object.entries(all)) {
-        it(`contains valid Web IDL for ${spec}`, function () {
-          validate(ast);
-        });
-      }
+  for (const [spec, ast] of Object.entries(all)) {
+    it(`contains valid Web IDL for ${spec}`, function () {
+      validate(ast);
     });
-
-    describe(`The combined Web IDL in the ${curatedView.name} view`, function () {
-      it('is valid Web IDL', function () {
-        this.slow(1000);
-        validate(Object.values(all).flat());
-      });
+  }
+  describe(`The combined Web IDL in the ${curatedView.name} view`, function () {
+    it('is valid Web IDL', function () {
+      validate(Object.values(all).flat());
     });
   });
-
-  // Dummy test needed for "before" to run and register late tests
-  // (test will fail if before function throws, e.g. because data is invalid)
-  it('contains data that can be parsed with webidl2.js', () => {});
 });
 
-
 describe(`The ${packageView.name} view of Web IDL extracts`, async () => {
-  before(async () => {
-    const all = await idl.parseAll(packageView.folder);
+  let all;
+  try {
+    all = await idl.parseAll({folder: packageView.folder});
+  } catch (err) {
+    it('contains data that can be parsed with webidl2.js', () => {throw err;});
+  }
 
-    describe(`The combined Web IDL in the ${packageView.name} view`, function () {
-      it('is valid Web IDL', function () {
-        this.slow(1000);
-        validate(Object.values(all).flat());
-      });
+  describe(`The combined Web IDL in the ${packageView.name} view`, function () {
+    it('is valid Web IDL', function () {
+      validate(Object.values(all).flat());
     });
   });
 
-  it('contains data that can be parsed with webidl2.js', () => {});
 });
 
diff --git a/test/schemas.js b/test/schemas.js
index 8b018fb3164d..816f37ee0eea 100644
--- a/test/schemas.js
+++ b/test/schemas.js
@@ -4,6 +4,7 @@
  * The tests run against the curated view of the extracts.
  */
 
+import { describe, it } from 'node:test';
 import { strict as assert } from 'node:assert';
 import fs from 'node:fs';
 import path from 'node:path';