@@ -1092,7 +1092,7 @@ EnvironmentOptionsParser::EnvironmentOptionsParser() {
             "Type-stripping for TypeScript files.",
             &EnvironmentOptions::strip_types,
             kAllowedInEnvvar,
-            true);
+            HAVE_AMARO);
   AddAlias("--experimental-strip-types", "--strip-types");
   AddOption("--experimental-transform-types",
             "enable transformation of TypeScript-only"
 
@@ -259,7 +259,7 @@ class EnvironmentOptions : public Options {
 
   std::vector<std::string> preload_esm_modules;
 
-  bool strip_types = true;
+  bool strip_types = HAVE_AMARO;
   bool experimental_transform_types = false;
 
   std::vector<std::string> user_argv;
 
@@ -21,6 +21,8 @@ function wrapScriptInUrlWorker(script) {
   `;
 }
 
+const onlyWithAmaro = { skip: !process.config.variables.node_use_amaro };
+
 describe('import.meta.main in evaluated scripts', () => {
   const importMetaMainScript = `
 import assert from 'node:assert/strict';
@@ -85,7 +87,7 @@ const { isMain: importedModuleIsMain } = await import(
 assert.strictEqual(importedModuleIsMain, false, 'import.meta.main should evaluate false in imported module');
 `;
 
-  it('should evaluate true in evaluated script', async () => {
+  it('should evaluate true in evaluated script', onlyWithAmaro, async () => {
     const result = await spawnPromisified(
       process.execPath,
       ['--input-type=module-typescript', '--disable-warning=ExperimentalWarning', '--eval', importMetaMainTSScript],
@@ -98,7 +100,7 @@ assert.strictEqual(importedModuleIsMain, false, 'import.meta.main should evaluat
     });
   });
 
-  it('should evaluate true in worker instantiated with module source by evaluated script', async () => {
+  it('should evaluate true in worker instantiated with module source by evaluated script', onlyWithAmaro, async () => {
     const result = await spawnPromisified(
       process.execPath,
       ['--input-type=module-typescript',
@@ -114,7 +116,7 @@ assert.strictEqual(importedModuleIsMain, false, 'import.meta.main should evaluat
     });
   });
 
-  it('should evaluate true in worker instantiated with `data:` URL by evaluated script', async () => {
+  it('should evaluate true in worker instantiated with `data:` URL by evaluated script', onlyWithAmaro, async () => {
     const result = await spawnPromisified(
       process.execPath,
       ['--input-type=module',
 
@@ -23,6 +23,8 @@ async function assertSpawnedProcess(args, options = {}, expected = {}) {
 // Common expectation for experimental feature warning in stderr
 const experimentalFeatureWarning = { stderr: /--entry-url is an experimental feature/ };
 
+const onlyWithAmaro = { skip: !process.config.variables.node_use_amaro };
+
 describe('--entry-url', { concurrency: true }, () => {
   it('should reject loading a path that contains %', async () => {
     await assertSpawnedProcess(
@@ -76,7 +78,7 @@ describe('--entry-url', { concurrency: true }, () => {
     );
   });
 
-  it('should support loading TypeScript URLs', { skip: !process.config.variables.node_use_amaro }, async () => {
+  it('should support loading TypeScript URLs', onlyWithAmaro, async () => {
     const typescriptUrls = [
       'typescript/cts/test-require-ts-file.cts',
       'typescript/mts/test-import-ts-file.mts',
 
@@ -198,6 +198,10 @@ try {
       subdirPackageType,
       expectedResolvedFormat,
       mainSuffix = '' ] = testVariant;
+    const skip = mainImportScript.endsWith('.ts') && !process.config.variables.node_use_amaro;
+    if (skip) {
+      return;
+    }
 
     const mDir = rel(`node_modules/${moduleName}`);
     const subDir = rel(`node_modules/${moduleName}/subdir`);
 
@@ -63,6 +63,11 @@ for (const [, envVar, config] of nodeOptionsCC.matchAll(addOptionRE)) {
     hasTrueAsDefaultValue = true;
   }
 
+  // Exception for HAVE_AMARO conditional default (defaults to true when Amaro is available)
+  if (config.includes('HAVE_AMARO')) {
+    hasTrueAsDefaultValue = true;
+  }
+
   if (
     envVar.startsWith('[') ||
     deprecated.includes(envVar) ||
 
@@ -2,7 +2,10 @@
 
 // This tests NODE_COMPILE_CACHE works for CommonJS with types.
 
-require('../common');
+const common = require('../common');
+if (!process.config.variables.node_use_amaro) {
+  common.skip('Requires Amaro');
+}
 const { spawnSyncAndAssert } = require('../common/child_process');
 const assert = require('assert');
 const tmpdir = require('../common/tmpdir');
 
@@ -2,7 +2,10 @@
 
 // This tests NODE_COMPILE_CACHE works for ESM with types.
 
-require('../common');
+const common = require('../common');
+if (!process.config.variables.node_use_amaro) {
+  common.skip('Requires Amaro');
+}
 const { spawnSyncAndAssert } = require('../common/child_process');
 const assert = require('assert');
 const tmpdir = require('../common/tmpdir');
 
@@ -3,7 +3,10 @@
 // This tests NODE_COMPILE_CACHE can handle cache invalidation
 // between strip-only TypeScript and transformed TypeScript.
 
-require('../common');
+const common = require('../common');
+if (!process.config.variables.node_use_amaro) {
+  common.skip('Requires Amaro');
+}
 const { spawnSyncAndAssert } = require('../common/child_process');
 const assert = require('assert');
 const tmpdir = require('../common/tmpdir');
 
@@ -3,7 +3,10 @@
 // This tests NODE_COMPILE_CACHE can be used for type stripping and ignores
 // --enable-source-maps as there's no difference in the code generated.
 
-require('../common');
+const common = require('../common');
+if (!process.config.variables.node_use_amaro) {
+  common.skip('Requires Amaro');
+}
 const { spawnSyncAndAssert } = require('../common/child_process');
 const assert = require('assert');
 const tmpdir = require('../common/tmpdir');