diff --git a/.eslintrc.js b/.eslintrc.js
index 5eed8409d2..5987e8c654 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -41,6 +41,7 @@ module.exports = {
         'test/es-module/test-esm-type-flag.js',
         'test/es-module/test-esm-type-flag-alias.js',
         '*.mjs',
+        'test/es-module/test-esm-example-loader.js',
       ],
       parserOptions: { sourceType: 'module' },
     },
diff --git a/doc/api/cli.md b/doc/api/cli.md
index de822b6a06..62e13496c0 100644
--- a/doc/api/cli.md
+++ b/doc/api/cli.md
@@ -268,6 +268,13 @@ default) is not firewall-protected.**
 
 See the [debugging security implications][] section for more information.
 
+### `--loader=file`
+<!-- YAML
+added: v9.0.0
+-->
+
+Specify the `file` of the custom [experimental ECMAScript Module][] loader.
+
 ### `--max-http-header-size=size`
 <!-- YAML
 added: v11.6.0
@@ -716,6 +723,7 @@ Node.js options that are allowed are:
 - `--inspect`
 - `--inspect-brk`
 - `--inspect-port`
+- `--loader`
 - `--max-http-header-size`
 - `--napi-modules`
 - `--no-deprecation`
@@ -903,6 +911,7 @@ greater than `4` (its current default value). For more information, see the
 [debugger]: debugger.html
 [debugging security implications]: https://nodejs.org/en/docs/guides/debugging-getting-started/#security-implications
 [emit_warning]: process.html#process_process_emitwarning_warning_type_code_ctor
+[experimental ECMAScript Module]: esm.html#esm_experimental_loader_hooks
 [libuv threadpool documentation]: http://docs.libuv.org/en/latest/threadpool.html
 [remote code execution]: https://www.owasp.org/index.php/Code_Injection
 [secureProtocol]: tls.html#tls_tls_createsecurecontext_options
diff --git a/doc/api/esm.md b/doc/api/esm.md
index 37f3d12df1..25c2e82673 100644
--- a/doc/api/esm.md
+++ b/doc/api/esm.md
@@ -289,6 +289,128 @@ READ_PACKAGE_JSON(_packageURL_)
 >    1. Throw an _Invalid Package Configuration_ error.
 > 1. Return the parsed JSON source of the file at _pjsonURL_.
 
+## Experimental Loader hooks
+
+**Note: This API is currently being redesigned and will still change.**.
+
+<!-- type=misc -->
+
+To customize the default module resolution, loader hooks can optionally be
+provided via a `--loader ./loader-name.mjs` argument to Node.js.
+
+When hooks are used they only apply to ES module loading and not to any
+CommonJS modules loaded.
+
+### Resolve hook
+
+The resolve hook returns the resolved file URL and module format for a
+given module specifier and parent file URL:
+
+```js
+const baseURL = new URL('file://');
+baseURL.pathname = `${process.cwd()}/`;
+
+export async function resolve(specifier,
+                              parentModuleURL = baseURL,
+                              defaultResolver) {
+  return {
+    url: new URL(specifier, parentModuleURL).href,
+    format: 'esm'
+  };
+}
+```
+
+The `parentModuleURL` is provided as `undefined` when performing main Node.js
+load itself.
+
+The default Node.js ES module resolution function is provided as a third
+argument to the resolver for easy compatibility workflows.
+
+In addition to returning the resolved file URL value, the resolve hook also
+returns a `format` property specifying the module format of the resolved
+module. This can be one of the following:
+
+| `format` | Description |
+| --- | --- |
+| `'module'` | Load a standard JavaScript module |
+| `'commonjs'` | Load a Node.js CommonJS module |
+| `'builtin'` | Load a Node.js builtin module |
+| `'dynamic'` | Use a [dynamic instantiate hook][] |
+
+For example, a dummy loader to load JavaScript restricted to browser resolution
+rules with only JS file extension and Node.js builtin modules support could
+be written:
+
+```js
+import path from 'path';
+import process from 'process';
+import Module from 'module';
+
+const builtins = Module.builtinModules;
+const JS_EXTENSIONS = new Set(['.js', '.mjs']);
+
+const baseURL = new URL('file://');
+baseURL.pathname = `${process.cwd()}/`;
+
+export function resolve(specifier, parentModuleURL = baseURL, defaultResolve) {
+  if (builtins.includes(specifier)) {
+    return {
+      url: specifier,
+      format: 'builtin'
+    };
+  }
+  if (/^\.{0,2}[/]/.test(specifier) !== true && !specifier.startsWith('file:')) {
+    // For node_modules support:
+    // return defaultResolve(specifier, parentModuleURL);
+    throw new Error(
+      `imports must begin with '/', './', or '../'; '${specifier}' does not`);
+  }
+  const resolved = new URL(specifier, parentModuleURL);
+  const ext = path.extname(resolved.pathname);
+  if (!JS_EXTENSIONS.has(ext)) {
+    throw new Error(
+      `Cannot load file with non-JavaScript file extension ${ext}.`);
+  }
+  return {
+    url: resolved.href,
+    format: 'esm'
+  };
+}
+```
+
+With this loader, running:
+
+```console
+NODE_OPTIONS='--experimental-modules --loader ./custom-loader.mjs' node x.js
+```
+
+would load the module `x.js` as an ES module with relative resolution support
+(with `node_modules` loading skipped in this example).
+
+### Dynamic instantiate hook
+
+To create a custom dynamic module that doesn't correspond to one of the
+existing `format` interpretations, the `dynamicInstantiate` hook can be used.
+This hook is called only for modules that return `format: 'dynamic'` from
+the `resolve` hook.
+
+```js
+export async function dynamicInstantiate(url) {
+  return {
+    exports: ['customExportName'],
+    execute: (exports) => {
+      // Get and set functions provided for pre-allocated export names
+      exports.customExportName.set('value');
+    }
+  };
+}
+```
+
+With the list of module exports provided upfront, the `execute` function will
+then be called at the exact point of module evaluation order for that module
+in the import tree.
+
 [Node.js EP for ES Modules]: https://github.com/nodejs/node-eps/blob/master/002-es-modules.md
+[dynamic instantiate hook]: #esm_dynamic_instantiate_hook
 [`module.createRequireFromPath()`]: modules.html#modules_module_createrequirefrompath_filename
 [ESM Minimal Kernel]: https://github.com/nodejs/modules/blob/master/doc/plan-for-new-modules-implementation.md
diff --git a/lib/internal/process/esm_loader.js b/lib/internal/process/esm_loader.js
index e405dc8b30..803c854d9a 100644
--- a/lib/internal/process/esm_loader.js
+++ b/lib/internal/process/esm_loader.js
@@ -7,6 +7,7 @@ const {
   ERR_INVALID_TYPE_FLAG,
   ERR_VM_DYNAMIC_IMPORT_CALLBACK_MISSING,
 } = require('internal/errors').codes;
+const { emitExperimentalWarning } = require('internal/util');
 
 const type = require('internal/options').getOptionValue('--type');
 if (type && type !== 'commonjs' && type !== 'module')
@@ -14,6 +15,7 @@ if (type && type !== 'commonjs' && type !== 'module')
 exports.typeFlag = type;
 
 const { Loader } = require('internal/modules/esm/loader');
+const { pathToFileURL } = require('internal/url');
 const {
   wrapToModuleMap,
 } = require('internal/vm/source_text_module');
@@ -44,8 +46,16 @@ exports.loaderPromise = new Promise((resolve) => loaderResolve = resolve);
 exports.ESMLoader = undefined;
 
 exports.initializeLoader = function(cwd, userLoader) {
-  const ESMLoader = new Loader();
+  let ESMLoader = new Loader();
   const loaderPromise = (async () => {
+    if (userLoader) {
+      emitExperimentalWarning('--loader');
+      const hooks = await ESMLoader.import(
+        userLoader, pathToFileURL(`${cwd}/`).href);
+      ESMLoader = new Loader();
+      ESMLoader.hook(hooks);
+      exports.ESMLoader = ESMLoader;
+    }
     return ESMLoader;
   })();
   loaderResolve(loaderPromise);
diff --git a/src/node_options.cc b/src/node_options.cc
index e76e1a0282..413169fde4 100644
--- a/src/node_options.cc
+++ b/src/node_options.cc
@@ -101,6 +101,10 @@ void PerIsolateOptions::CheckOptions(std::vector<std::string>* errors) {
 }
 
 void EnvironmentOptions::CheckOptions(std::vector<std::string>* errors) {
+  if (!userland_loader.empty() && !experimental_modules) {
+    errors->push_back("--loader requires --experimental-modules be enabled");
+  }
+
   if (syntax_check_only && has_eval_string) {
     errors->push_back("either --check or --eval can be used, not both");
   }
@@ -242,6 +246,11 @@ EnvironmentOptionsParser::EnvironmentOptionsParser() {
             "(default: llhttp).",
             &EnvironmentOptions::http_parser,
             kAllowedInEnvironment);
+  AddOption("--loader",
+            "(with --experimental-modules) use the specified file as a "
+            "custom loader",
+            &EnvironmentOptions::userland_loader,
+            kAllowedInEnvironment);
   AddOption("--no-deprecation",
             "silence deprecation warnings",
             &EnvironmentOptions::no_deprecation,
diff --git a/src/node_options.h b/src/node_options.h
index ee4cc98c9b..83c3be8674 100644
--- a/src/node_options.h
+++ b/src/node_options.h
@@ -105,6 +105,7 @@ class EnvironmentOptions : public Options {
   bool trace_deprecation = false;
   bool trace_sync_io = false;
   bool trace_warnings = false;
+  std::string userland_loader;
 
   bool syntax_check_only = false;
   bool has_eval_string = false;
diff --git a/test/es-module/test-esm-example-loader.js b/test/es-module/test-esm-example-loader.js
new file mode 100644
index 0000000000..0b0001acea
--- /dev/null
+++ b/test/es-module/test-esm-example-loader.js
@@ -0,0 +1,6 @@
+// Flags: --experimental-modules --loader ./test/fixtures/es-module-loaders/example-loader.mjs
+/* eslint-disable node-core/required-modules */
+import assert from 'assert';
+import ok from '../fixtures/es-modules/test-esm-ok.mjs';
+
+assert(ok);
diff --git a/test/es-module/test-esm-loader-dependency.mjs b/test/es-module/test-esm-loader-dependency.mjs
new file mode 100644
index 0000000000..1ed8685a6f
--- /dev/null
+++ b/test/es-module/test-esm-loader-dependency.mjs
@@ -0,0 +1,5 @@
+// Flags: --experimental-modules --loader ./test/fixtures/es-module-loaders/loader-with-dep.mjs
+/* eslint-disable node-core/required-modules */
+import '../fixtures/es-modules/test-esm-ok.mjs';
+
+// We just test that this module doesn't fail loading
diff --git a/test/es-module/test-esm-loader-invalid-format.mjs b/test/es-module/test-esm-loader-invalid-format.mjs
new file mode 100644
index 0000000000..c3f3a87407
--- /dev/null
+++ b/test/es-module/test-esm-loader-invalid-format.mjs
@@ -0,0 +1,12 @@
+// Flags: --experimental-modules --loader ./test/fixtures/es-module-loaders/loader-invalid-format.mjs
+/* eslint-disable node-core/required-modules */
+import { expectsError, mustCall } from '../common/index.mjs';
+import assert from 'assert';
+
+import('../fixtures/es-modules/test-esm-ok.mjs')
+.then(assert.fail, expectsError({
+  code: 'ERR_INVALID_RETURN_PROPERTY_VALUE',
+  message: 'Expected string to be returned for the "format" from the ' +
+           '"loader resolve" function but got type undefined.'
+}))
+.then(mustCall());
diff --git a/test/es-module/test-esm-loader-invalid-url.mjs b/test/es-module/test-esm-loader-invalid-url.mjs
new file mode 100644
index 0000000000..9cf17b2478
--- /dev/null
+++ b/test/es-module/test-esm-loader-invalid-url.mjs
@@ -0,0 +1,14 @@
+// Flags: --experimental-modules --loader ./test/fixtures/es-module-loaders/loader-invalid-url.mjs
+/* eslint-disable node-core/required-modules */
+
+import { expectsError, mustCall } from '../common/index.mjs';
+import assert from 'assert';
+
+import('../fixtures/es-modules/test-esm-ok.mjs')
+.then(assert.fail, expectsError({
+  code: 'ERR_INVALID_RETURN_PROPERTY',
+  message: 'Expected a valid url to be returned for the "url" from the ' +
+           '"loader resolve" function but got ' +
+           '../fixtures/es-modules/test-esm-ok.mjs.'
+}))
+.then(mustCall());
diff --git a/test/es-module/test-esm-loader-missing-dynamic-instantiate-hook.mjs b/test/es-module/test-esm-loader-missing-dynamic-instantiate-hook.mjs
new file mode 100644
index 0000000000..ab2da7adce
--- /dev/null
+++ b/test/es-module/test-esm-loader-missing-dynamic-instantiate-hook.mjs
@@ -0,0 +1,10 @@
+// Flags: --experimental-modules --loader ./test/fixtures/es-module-loaders/missing-dynamic-instantiate-hook.mjs
+/* eslint-disable node-core/required-modules */
+
+import { expectsError } from '../common/index.mjs';
+
+import('test').catch(expectsError({
+  code: 'ERR_MISSING_DYNAMIC_INSTANTIATE_HOOK',
+  message: 'The ES Module loader may not return a format of \'dynamic\' ' +
+    'when no dynamicInstantiate function was provided'
+}));
diff --git a/test/es-module/test-esm-named-exports.mjs b/test/es-module/test-esm-named-exports.mjs
new file mode 100644
index 0000000000..e235f598cb
--- /dev/null
+++ b/test/es-module/test-esm-named-exports.mjs
@@ -0,0 +1,9 @@
+// Flags: --experimental-modules --loader ./test/fixtures/es-module-loaders/builtin-named-exports-loader.mjs
+/* eslint-disable node-core/required-modules */
+import '../common/index.mjs';
+import { readFile } from 'fs';
+import assert from 'assert';
+import ok from '../fixtures/es-modules/test-esm-ok.mjs';
+
+assert(ok);
+assert(readFile);
diff --git a/test/es-module/test-esm-preserve-symlinks-not-found-plain.mjs b/test/es-module/test-esm-preserve-symlinks-not-found-plain.mjs
new file mode 100644
index 0000000000..2ca0f56581
--- /dev/null
+++ b/test/es-module/test-esm-preserve-symlinks-not-found-plain.mjs
@@ -0,0 +1,3 @@
+// Flags: --experimental-modules --loader ./test/fixtures/es-module-loaders/not-found-assert-loader.mjs
+/* eslint-disable node-core/required-modules */
+import './not-found.js';
diff --git a/test/es-module/test-esm-preserve-symlinks-not-found.mjs b/test/es-module/test-esm-preserve-symlinks-not-found.mjs
new file mode 100644
index 0000000000..b5be2d7e63
--- /dev/null
+++ b/test/es-module/test-esm-preserve-symlinks-not-found.mjs
@@ -0,0 +1,3 @@
+// Flags: --experimental-modules --loader ./test/fixtures/es-module-loaders/not-found-assert-loader.mjs
+/* eslint-disable node-core/required-modules */
+import './not-found.mjs';
diff --git a/test/es-module/test-esm-resolve-hook.mjs b/test/es-module/test-esm-resolve-hook.mjs
new file mode 100644
index 0000000000..e326d20b6d
--- /dev/null
+++ b/test/es-module/test-esm-resolve-hook.mjs
@@ -0,0 +1,8 @@
+// Flags: --experimental-modules --loader ./test/fixtures/es-module-loaders/js-loader.mjs
+/* eslint-disable node-core/required-modules */
+import { namedExport } from '../fixtures/es-module-loaders/js-as-esm.js';
+import assert from 'assert';
+import ok from '../fixtures/es-modules/test-esm-ok.mjs';
+
+assert(ok);
+assert(namedExport);
diff --git a/test/es-module/test-esm-shared-loader-dep.mjs b/test/es-module/test-esm-shared-loader-dep.mjs
new file mode 100644
index 0000000000..b8953ab1ec
--- /dev/null
+++ b/test/es-module/test-esm-shared-loader-dep.mjs
@@ -0,0 +1,11 @@
+// Flags: --experimental-modules --loader ./test/fixtures/es-module-loaders/loader-shared-dep.mjs
+/* eslint-disable node-core/required-modules */
+import { createRequire } from '../common/index.mjs';
+
+import assert from 'assert';
+import '../fixtures/es-modules/test-esm-ok.mjs';
+
+const require = createRequire(import.meta.url);
+const dep = require('../fixtures/es-module-loaders/loader-dep.js');
+
+assert.strictEqual(dep.format, 'module');
diff --git a/test/es-module/test-esm-throw-undefined.mjs b/test/es-module/test-esm-throw-undefined.mjs
new file mode 100644
index 0000000000..97e917da5e
--- /dev/null
+++ b/test/es-module/test-esm-throw-undefined.mjs
@@ -0,0 +1,16 @@
+// Flags: --experimental-modules
+/* eslint-disable node-core/required-modules */
+
+import '../common/index.mjs';
+import assert from 'assert';
+
+async function doTest() {
+  await assert.rejects(
+    async () => {
+      await import('../fixtures/es-module-loaders/throw-undefined.mjs');
+    },
+    (e) => e === undefined
+  );
+}
+
+doTest();
diff --git a/test/fixtures/es-module-loaders/builtin-named-exports-loader.mjs b/test/fixtures/es-module-loaders/builtin-named-exports-loader.mjs
new file mode 100644
index 0000000000..a944c4fd5e
--- /dev/null
+++ b/test/fixtures/es-module-loaders/builtin-named-exports-loader.mjs
@@ -0,0 +1,24 @@
+import module from 'module';
+
+export function dynamicInstantiate(url) {
+  const builtinInstance = module._load(url.substr(5));
+  const builtinExports = ['default', ...Object.keys(builtinInstance)];
+  return {
+    exports: builtinExports,
+    execute: exports => {
+      for (let name of builtinExports)
+        exports[name].set(builtinInstance[name]);
+      exports.default.set(builtinInstance);
+    }
+  };
+}
+
+export function resolve(specifier, base, defaultResolver) {
+  if (module.builtinModules.includes(specifier)) {
+    return {
+      url: `node:${specifier}`,
+      format: 'dynamic'
+    };
+  }
+  return defaultResolver(specifier, base);
+}
diff --git a/test/fixtures/es-module-loaders/example-loader.mjs b/test/fixtures/es-module-loaders/example-loader.mjs
new file mode 100644
index 0000000000..d8e0ddcba3
--- /dev/null
+++ b/test/fixtures/es-module-loaders/example-loader.mjs
@@ -0,0 +1,34 @@
+import url from 'url';
+import path from 'path';
+import process from 'process';
+import { builtinModules } from 'module';
+
+const JS_EXTENSIONS = new Set(['.js', '.mjs']);
+
+const baseURL = new url.URL('file://');
+baseURL.pathname = process.cwd() + '/';
+
+export function resolve(specifier, parentModuleURL = baseURL /*, defaultResolve */) {
+  if (builtinModules.includes(specifier)) {
+    return {
+      url: specifier,
+      format: 'builtin'
+    };
+  }
+  if (/^\.{0,2}[/]/.test(specifier) !== true && !specifier.startsWith('file:')) {
+    // For node_modules support:
+    // return defaultResolve(specifier, parentModuleURL);
+    throw new Error(
+      `imports must begin with '/', './', or '../'; '${specifier}' does not`);
+  }
+  const resolved = new url.URL(specifier, parentModuleURL);
+  const ext = path.extname(resolved.pathname);
+  if (!JS_EXTENSIONS.has(ext)) {
+    throw new Error(
+      `Cannot load file with non-JavaScript file extension ${ext}.`);
+  }
+  return {
+    url: resolved.href,
+    format: 'module'
+  };
+}
diff --git a/test/fixtures/es-module-loaders/js-as-esm.js b/test/fixtures/es-module-loaders/js-as-esm.js
new file mode 100644
index 0000000000..b4d2741b2f
--- /dev/null
+++ b/test/fixtures/es-module-loaders/js-as-esm.js
@@ -0,0 +1 @@
+export const namedExport = 'named-export';
diff --git a/test/fixtures/es-module-loaders/js-loader.mjs b/test/fixtures/es-module-loaders/js-loader.mjs
new file mode 100644
index 0000000000..4b8a0fc365
--- /dev/null
+++ b/test/fixtures/es-module-loaders/js-loader.mjs
@@ -0,0 +1,20 @@
+import { URL } from 'url';
+import { builtinModules } from 'module';
+
+const baseURL = new URL('file://');
+baseURL.pathname = process.cwd() + '/';
+
+export function resolve (specifier, base = baseURL) {
+  if (builtinModules.includes(specifier)) {
+    return {
+      url: specifier,
+      format: 'builtin'
+    };
+  }
+  // load all dependencies as esm, regardless of file extension
+  const url = new URL(specifier, base).href;
+  return {
+    url,
+    format: 'module'
+  };
+}
diff --git a/test/fixtures/es-module-loaders/loader-dep.js b/test/fixtures/es-module-loaders/loader-dep.js
new file mode 100644
index 0000000000..c8154ac5db
--- /dev/null
+++ b/test/fixtures/es-module-loaders/loader-dep.js
@@ -0,0 +1 @@
+exports.format = 'module';
diff --git a/test/fixtures/es-module-loaders/loader-invalid-format.mjs b/test/fixtures/es-module-loaders/loader-invalid-format.mjs
new file mode 100644
index 0000000000..17a0dcd04d
--- /dev/null
+++ b/test/fixtures/es-module-loaders/loader-invalid-format.mjs
@@ -0,0 +1,8 @@
+export async function resolve(specifier, parentModuleURL, defaultResolve) {
+  if (parentModuleURL && specifier === '../fixtures/es-modules/test-esm-ok.mjs') {
+    return {
+      url: 'file:///asdf'
+    };
+  }
+  return defaultResolve(specifier, parentModuleURL);
+}
diff --git a/test/fixtures/es-module-loaders/loader-invalid-url.mjs b/test/fixtures/es-module-loaders/loader-invalid-url.mjs
new file mode 100644
index 0000000000..f653155899
--- /dev/null
+++ b/test/fixtures/es-module-loaders/loader-invalid-url.mjs
@@ -0,0 +1,10 @@
+/* eslint-disable node-core/required-modules */
+export async function resolve(specifier, parentModuleURL, defaultResolve) {
+  if (parentModuleURL && specifier === '../fixtures/es-modules/test-esm-ok.mjs') {
+    return {
+      url: specifier,
+      format: 'esm'
+    };
+  }
+  return defaultResolve(specifier, parentModuleURL);
+}
diff --git a/test/fixtures/es-module-loaders/loader-shared-dep.mjs b/test/fixtures/es-module-loaders/loader-shared-dep.mjs
new file mode 100644
index 0000000000..3acafcce1e
--- /dev/null
+++ b/test/fixtures/es-module-loaders/loader-shared-dep.mjs
@@ -0,0 +1,11 @@
+import assert from 'assert';
+
+import {createRequire} from '../../common/index.mjs';
+
+const require = createRequire(import.meta.url);
+const dep = require('./loader-dep.js');
+
+export function resolve(specifier, base, defaultResolve) {
+  assert.strictEqual(dep.format, 'module');
+  return defaultResolve(specifier, base);
+}
diff --git a/test/fixtures/es-module-loaders/loader-unknown-builtin-module.mjs b/test/fixtures/es-module-loaders/loader-unknown-builtin-module.mjs
new file mode 100644
index 0000000000..e7c6c8ff34
--- /dev/null
+++ b/test/fixtures/es-module-loaders/loader-unknown-builtin-module.mjs
@@ -0,0 +1,6 @@
+export async function resolve(specifier, parent, defaultResolve) {
+  if (specifier === 'unknown-builtin-module') {
+    return { url: 'unknown-builtin-module', format: 'builtin' };
+  }
+  return defaultResolve(specifier, parent);
+}
\ No newline at end of file
diff --git a/test/fixtures/es-module-loaders/loader-with-dep.mjs b/test/fixtures/es-module-loaders/loader-with-dep.mjs
new file mode 100644
index 0000000000..5afd3b2e21
--- /dev/null
+++ b/test/fixtures/es-module-loaders/loader-with-dep.mjs
@@ -0,0 +1,11 @@
+import {createRequire} from '../../common/index.mjs';
+
+const require = createRequire(import.meta.url);
+const dep = require('./loader-dep.js');
+
+export function resolve (specifier, base, defaultResolve) {
+  return {
+    url: defaultResolve(specifier, base).url,
+    format: dep.format
+  };
+}
diff --git a/test/fixtures/es-module-loaders/missing-dynamic-instantiate-hook.mjs b/test/fixtures/es-module-loaders/missing-dynamic-instantiate-hook.mjs
new file mode 100644
index 0000000000..6993747fcc
--- /dev/null
+++ b/test/fixtures/es-module-loaders/missing-dynamic-instantiate-hook.mjs
@@ -0,0 +1,6 @@
+export function resolve(specifier, parentModule, defaultResolver) {
+  if (specifier !== 'test') {
+    return defaultResolver(specifier, parentModule);
+  }
+  return { url: 'file://', format: 'dynamic' };
+}
diff --git a/test/fixtures/es-module-loaders/module-named-exports.mjs b/test/fixtures/es-module-loaders/module-named-exports.mjs
new file mode 100644
index 0000000000..04f7f43ebd
--- /dev/null
+++ b/test/fixtures/es-module-loaders/module-named-exports.mjs
@@ -0,0 +1,2 @@
+export const foo = 'foo';
+export const bar = 'bar';
diff --git a/test/fixtures/es-module-loaders/not-found-assert-loader.mjs b/test/fixtures/es-module-loaders/not-found-assert-loader.mjs
new file mode 100644
index 0000000000..d3eebcd47e
--- /dev/null
+++ b/test/fixtures/es-module-loaders/not-found-assert-loader.mjs
@@ -0,0 +1,22 @@
+import assert from 'assert';
+
+// a loader that asserts that the defaultResolve will throw "not found"
+// (skipping the top-level main of course)
+let mainLoad = true;
+export async function resolve (specifier, base, defaultResolve) {
+  if (mainLoad) {
+    mainLoad = false;
+    return defaultResolve(specifier, base);
+  }
+  try {
+    await defaultResolve(specifier, base);
+  }
+  catch (e) {
+    assert.strictEqual(e.code, 'ERR_MODULE_NOT_FOUND');
+    return {
+      format: 'builtin',
+      url: 'fs'
+    };
+  }
+  assert.fail(`Module resolution for ${specifier} should be throw ERR_MODULE_NOT_FOUND`);
+}
diff --git a/test/fixtures/es-module-loaders/syntax-error-import.mjs b/test/fixtures/es-module-loaders/syntax-error-import.mjs
new file mode 100644
index 0000000000..3a6bc5effc
--- /dev/null
+++ b/test/fixtures/es-module-loaders/syntax-error-import.mjs
@@ -0,0 +1 @@
+import { foo, notfound } from './module-named-exports.mjs';
diff --git a/test/fixtures/es-module-loaders/syntax-error.mjs b/test/fixtures/es-module-loaders/syntax-error.mjs
new file mode 100644
index 0000000000..bda4a7e6eb
--- /dev/null
+++ b/test/fixtures/es-module-loaders/syntax-error.mjs
@@ -0,0 +1,2 @@
+'use strict';
+await async () => 0;
diff --git a/test/fixtures/es-module-loaders/throw-undefined.mjs b/test/fixtures/es-module-loaders/throw-undefined.mjs
new file mode 100644
index 0000000000..0349ae112d
--- /dev/null
+++ b/test/fixtures/es-module-loaders/throw-undefined.mjs
@@ -0,0 +1,4 @@
+'use strict';
+/* eslint-disable node-core/required-modules */
+
+throw undefined;
diff --git a/test/message/esm_display_syntax_error.out b/test/message/esm_display_syntax_error.out
index 2700fd894c..8f17d5cd7a 100644
--- a/test/message/esm_display_syntax_error.out
+++ b/test/message/esm_display_syntax_error.out
@@ -2,5 +2,6 @@
 file:///*/test/message/esm_display_syntax_error.mjs:3
 await async () => 0;
 ^^^^^
+
 SyntaxError: Unexpected reserved word
     at Loader.<anonymous> (internal/modules/esm/translators.js:*:*)
diff --git a/test/message/esm_display_syntax_error_import.mjs b/test/message/esm_display_syntax_error_import.mjs
new file mode 100644
index 0000000000..12d10270e9
--- /dev/null
+++ b/test/message/esm_display_syntax_error_import.mjs
@@ -0,0 +1,7 @@
+// Flags:  --experimental-modules
+/* eslint-disable no-unused-vars, node-core/required-modules */
+import '../common/index.mjs';
+import {
+  foo,
+  notfound
+} from '../fixtures/es-module-loaders/module-named-exports.mjs';
diff --git a/test/message/esm_display_syntax_error_import.out b/test/message/esm_display_syntax_error_import.out
new file mode 100644
index 0000000000..48f2e2fb74
--- /dev/null
+++ b/test/message/esm_display_syntax_error_import.out
@@ -0,0 +1,6 @@
+(node:*) ExperimentalWarning: The ESM module loader is experimental.
+file:///*/test/message/esm_display_syntax_error_import.mjs:6
+  notfound
+  ^^^^^^^^
+SyntaxError: The requested module '../fixtures/es-module-loaders/module-named-exports.mjs' does not provide an export named 'notfound'
+    at ModuleJob._instantiate (internal/modules/esm/module_job.js:*:*)
diff --git a/test/message/esm_display_syntax_error_import_module.mjs b/test/message/esm_display_syntax_error_import_module.mjs
new file mode 100644
index 0000000000..a53bbbcd19
--- /dev/null
+++ b/test/message/esm_display_syntax_error_import_module.mjs
@@ -0,0 +1,4 @@
+// Flags:  --experimental-modules
+/* eslint-disable node-core/required-modules */
+import '../common/index.mjs';
+import '../fixtures/es-module-loaders/syntax-error-import.mjs';
diff --git a/test/message/esm_display_syntax_error_import_module.out b/test/message/esm_display_syntax_error_import_module.out
new file mode 100644
index 0000000000..3e1024db8a
--- /dev/null
+++ b/test/message/esm_display_syntax_error_import_module.out
@@ -0,0 +1,6 @@
+(node:*) ExperimentalWarning: The ESM module loader is experimental.
+file:///*/test/fixtures/es-module-loaders/syntax-error-import.mjs:1
+import { foo, notfound } from './module-named-exports.mjs';
+              ^^^^^^^^
+SyntaxError: The requested module './module-named-exports.mjs' does not provide an export named 'notfound'
+    at ModuleJob._instantiate (internal/modules/esm/module_job.js:*:*)
diff --git a/test/message/esm_display_syntax_error_module.mjs b/test/message/esm_display_syntax_error_module.mjs
new file mode 100644
index 0000000000..5905d2a954
--- /dev/null
+++ b/test/message/esm_display_syntax_error_module.mjs
@@ -0,0 +1,4 @@
+// Flags:  --experimental-modules
+/* eslint-disable node-core/required-modules */
+import '../common/index.mjs';
+import '../fixtures/es-module-loaders/syntax-error.mjs';
diff --git a/test/message/esm_display_syntax_error_module.out b/test/message/esm_display_syntax_error_module.out
new file mode 100644
index 0000000000..7dbbd32f1f
--- /dev/null
+++ b/test/message/esm_display_syntax_error_module.out
@@ -0,0 +1,7 @@
+(node:*) ExperimentalWarning: The ESM module loader is experimental.
+file:///*/test/fixtures/es-module-loaders/syntax-error.mjs:2
+await async () => 0;
+^^^^^
+
+SyntaxError: Unexpected reserved word
+    at Loader.<anonymous> (internal/modules/esm/translators.js:*:*)
diff --git a/test/parallel/test-loaders-unknown-builtin-module.mjs b/test/parallel/test-loaders-unknown-builtin-module.mjs
new file mode 100644
index 0000000000..5f47f191f5
--- /dev/null
+++ b/test/parallel/test-loaders-unknown-builtin-module.mjs
@@ -0,0 +1,13 @@
+// Flags: --experimental-modules --loader ./test/fixtures/es-module-loaders/loader-unknown-builtin-module.mjs
+/* eslint-disable node-core/required-modules */
+import { expectsError, mustCall } from '../common/index.mjs';
+import assert from 'assert';
+
+const unknownBuiltinModule = 'unknown-builtin-module';
+
+import(unknownBuiltinModule)
+.then(assert.fail, expectsError({
+  code: 'ERR_UNKNOWN_BUILTIN_MODULE',
+  message: `No such built-in module: ${unknownBuiltinModule}`
+}))
+.then(mustCall());