diff --git a/package.json b/package.json
index 44e5d00..79f8019 100644
--- a/package.json
+++ b/package.json
@@ -32,7 +32,7 @@
 		"prepack": "pnpm build && clean-pkg-json"
 	},
 	"dependencies": {
-		"@esbuild-kit/core-utils": "^3.2.3",
+		"@esbuild-kit/core-utils": "^3.3.0",
 		"get-tsconfig": "^4.7.0"
 	},
 	"devDependencies": {
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index f9417b5..000fdd2 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -6,8 +6,8 @@ settings:
 
 dependencies:
   '@esbuild-kit/core-utils':
-    specifier: ^3.2.3
-    version: 3.2.3
+    specifier: ^3.3.0
+    version: 3.3.0
   get-tsconfig:
     specifier: ^4.7.0
     version: 4.7.0
@@ -91,8 +91,8 @@ packages:
       js-tokens: 4.0.0
     dev: true
 
-  /@esbuild-kit/core-utils@3.2.3:
-    resolution: {integrity: sha512-daTXIDXv6lTpADQYTfY9BgHfL3HjVfY7xD8aOuPWtD1bJdqk9hAtHK5cErBcxcBtjFcfB0B2tftFtW01jTveKw==}
+  /@esbuild-kit/core-utils@3.3.0:
+    resolution: {integrity: sha512-jTtSvVpr5ygNXyPXf9IBbCrKQ0uckq6vWkcGfy1fEr9KjkKdnFn4kFAGjpqZDZim1wsTwh/Be+lhAUemEmxEYA==}
     dependencies:
       esbuild: 0.18.20
       source-map-support: 0.5.21
diff --git a/src/loaders.ts b/src/loaders.ts
index b9bff7e..64a2fed 100644
--- a/src/loaders.ts
+++ b/src/loaders.ts
@@ -1,6 +1,9 @@
+import type { MessagePort } from 'node:worker_threads';
 import path from 'path';
 import { pathToFileURL, fileURLToPath } from 'url';
-import type { ResolveFnOutput, ResolveHookContext, LoadHook } from 'module';
+import type {
+	ResolveFnOutput, ResolveHookContext, LoadHook, GlobalPreloadHook,
+} from 'module';
 import {
 	transform,
 	transformDynamicImport,
@@ -31,6 +34,20 @@ type resolve = (
 	recursiveCall?: boolean,
 ) => MaybePromise<ResolveFnOutput>;
 
+/**
+ * Technically globalPreload is deprecated so it should be in loaders-deprecated
+ * but it shares a closure with the new load hook
+ */
+let mainThreadPort: MessagePort | undefined;
+export const globalPreload: GlobalPreloadHook = ({ port }) => {
+	mainThreadPort = port;
+	return `
+	const require = getBuiltin('module').createRequire(getBuiltin('process').cwd() + '/<preload>');
+	require('@esbuild-kit/core-utils').installSourceMapSupport(port);
+	port.unref(); // Allows process to exit without waiting for port to close
+	`;
+};
+
 const extensions = ['.js', '.json', '.ts', '.tsx', '.jsx'] as const;
 
 async function tryExtensions(
@@ -223,6 +240,7 @@ export const load: LoadHook = async function (
 	const code = loaded.source.toString();
 
 	if (
+		// Support named imports in JSON modules
 		loaded.format === 'json'
 		|| tsExtensionsPattern.test(url)
 	) {
@@ -236,7 +254,7 @@ export const load: LoadHook = async function (
 
 		return {
 			format: 'module',
-			source: applySourceMap(transformed, url),
+			source: applySourceMap(transformed, url, mainThreadPort),
 		};
 	}
 
@@ -246,6 +264,7 @@ export const load: LoadHook = async function (
 			loaded.source = applySourceMap(
 				dynamicImportTransformed,
 				url,
+				mainThreadPort,
 			);
 		}
 	}
diff --git a/tests/index.ts b/tests/index.ts
index 7ae03c6..0aa06e9 100644
--- a/tests/index.ts
+++ b/tests/index.ts
@@ -11,6 +11,7 @@ const nodeVersions = [
 				'16',
 				'17',
 				'18',
+				'20',
 			]
 			: []
 	),
diff --git a/tests/specs/typescript/tsconfig.ts b/tests/specs/typescript/tsconfig.ts
index 2ae6e9c..eb5eeb9 100644
--- a/tests/specs/typescript/tsconfig.ts
+++ b/tests/specs/typescript/tsconfig.ts
@@ -1,3 +1,5 @@
+import path from 'path';
+import fs from 'fs/promises';
 import { testSuite, expect } from 'manten';
 import { createFixture } from 'fs-fixture';
 import type { NodeApis } from '../../utils/node-with-loader.js';
@@ -37,6 +39,12 @@ export default testSuite(async ({ describe }, node: NodeApis) => {
 					},
 				});
 
+				await fs.symlink(
+					path.resolve('node_modules'),
+					path.join(fixture.path, 'node_modules'),
+					'dir',
+				);
+
 				onTestFinish(async () => await fixture.rm());
 
 				// Strict mode is not tested because ESM is strict by default
@@ -71,6 +79,12 @@ export default testSuite(async ({ describe }, node: NodeApis) => {
 					'src/jsx.jsx': checkJsx,
 				});
 
+				await fs.symlink(
+					path.resolve('node_modules'),
+					path.join(fixture.path, 'node_modules'),
+					'dir',
+				);
+
 				onTestFinish(async () => await fixture.rm());
 
 				const jsxJs = await node.load('./src/jsx.jsx', {