From 219b2ad82b9dcd5c3b7a79653316d1c2451e873f Mon Sep 17 00:00:00 2001
From: Claude <noreply@anthropic.com>
Date: Thu, 1 Oct 2026 20:15:01 +0000
Subject: [PATCH 1/2] Add an experimental gjs|codegen format: templates
 compiled straight to DOM ops

Adds a `codegen` flavor to the gjs compiler. Instead of compiling
<template>s to the wire format (and then to VM bytecode at runtime), the
templates are compiled directly to JavaScript that builds and updates
DOM, using a small runtime (`@glimmer/dom`).

The compiler and runtime are vendored from an ember.js branch:
https://github.com/NullVoxPopuli-ai-agent/ember.js/tree/claude/gallant-heisenberg-aovzyr

- repl-sdk: `gjs.codegen` config, sharing the gjs pipeline, but with the
  codegen babel plugin, and rendering with @glimmer/dom
- ember-repl: provides `@glimmer/dom` to compiled code
- repl app: 'Glimmer JS (codegen, experimental)' format + a demo

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01H2cNyDMVxZb1xQB6oCzX89
---
 apps/repl/app/components/verify-danger.gts    |  12 +-
 apps/repl/app/languages.gts                   |   7 +
 apps/repl/app/snippets.ts                     |   7 +-
 apps/repl/app/templates/edit/format-menu.gts  |   1 +
 .../edit/layout/controls/formatting.ts        |   4 +
 apps/repl/public/samples/gjs-codegen-demo.gjs |  81 ++
 .../ember-repl/src/services/known-modules.ts  |   7 +
 packages/ember-repl/src/vendor/glimmer-dom.js | 860 +++++++++++++++++
 packages/repl-sdk/src/compilers/ember.js      |  37 +-
 packages/repl-sdk/src/compilers/ember/gjs.js  |  42 +-
 .../ember/vendor/codegen-compiler.js          | 900 ++++++++++++++++++
 11 files changed, 1936 insertions(+), 22 deletions(-)
 create mode 100644 apps/repl/public/samples/gjs-codegen-demo.gjs
 create mode 100644 packages/ember-repl/src/vendor/glimmer-dom.js
 create mode 100644 packages/repl-sdk/src/compilers/ember/vendor/codegen-compiler.js

diff --git a/apps/repl/app/components/verify-danger.gts b/apps/repl/app/components/verify-danger.gts
index bb32a5562..302378c50 100644
--- a/apps/repl/app/components/verify-danger.gts
+++ b/apps/repl/app/components/verify-danger.gts
@@ -17,6 +17,7 @@ const ALLOWED = Object.freeze([]);
 const MARKUP_FORMATS = new Set([
   'js',
   'gjs',
+  'gjs|codegen',
   'gts',
   'vue',
   'jsx',
@@ -27,7 +28,16 @@ const MARKUP_FORMATS = new Set([
   'hbs',
   'hbs|ember',
 ]);
-const SCRIPT_FORMATS = new Set(['js', 'gjs', 'gts', 'vue', 'jsx', 'jsx|react', 'svelte']);
+const SCRIPT_FORMATS = new Set([
+  'js',
+  'gjs',
+  'gjs|codegen',
+  'gts',
+  'vue',
+  'jsx',
+  'jsx|react',
+  'svelte',
+]);
 
 function couldHaveMarkup(format: Format) {
   return MARKUP_FORMATS.has(format);
diff --git a/apps/repl/app/languages.gts b/apps/repl/app/languages.gts
index aef90fd88..5d70f067c 100644
--- a/apps/repl/app/languages.gts
+++ b/apps/repl/app/languages.gts
@@ -52,6 +52,13 @@ const languages = {
       </span>
     </template>,
   },
+  'gjs|codegen': {
+    name: 'Glimmer JS (codegen, experimental)',
+    ext: 'gjs',
+    icon: <template>
+      <span>{{{FileGlimmer}}}</span>
+    </template>,
+  },
   // an alias
   get hbs() {
     return languages['hbs|ember'];
diff --git a/apps/repl/app/snippets.ts b/apps/repl/app/snippets.ts
index 0f500da75..01812f543 100644
--- a/apps/repl/app/snippets.ts
+++ b/apps/repl/app/snippets.ts
@@ -130,6 +130,11 @@ export const ALL = [
     path: '/samples/nested-ember-routing-demo.gjs',
   },
   { format: 'gts', label: 'Ember GTS', path: '/samples/gts-demo.gts' },
+  {
+    format: 'gjs|codegen',
+    label: 'Ember GJS (codegen, experimental)',
+    path: '/samples/gjs-codegen-demo.gjs',
+  },
   { format: 'svelte', label: 'Svelte', path: '/samples/svelte-demo.svelte' },
   { format: 'js', label: 'Vanilla JS', path: '/samples/js-demo.js' },
   // Yaml
@@ -195,7 +200,7 @@ export async function getFromLabel(label: string): Promise<string> {
 }
 
 export function defaultSnippetForFormat(format: string) {
-  if (format === 'gjs') {
+  if (format === 'gjs' || format === 'gjs|codegen') {
     return DEFAULT_GJS;
   }
 
diff --git a/apps/repl/app/templates/edit/format-menu.gts b/apps/repl/app/templates/edit/format-menu.gts
index eb30df2c4..0a5d9bb39 100644
--- a/apps/repl/app/templates/edit/format-menu.gts
+++ b/apps/repl/app/templates/edit/format-menu.gts
@@ -106,6 +106,7 @@ export class FormatMenu extends Component<{ Element: HTMLButtonElement }> {
           <Button @format="js" />
           <Button @format="gjs" />
           <Button @format="gts" />
+          <Button @format="gjs|codegen" />
           <Button @format="hbs" />
           <Button @format="svelte" />
           <Button @format="vue" />
diff --git a/apps/repl/app/templates/edit/layout/controls/formatting.ts b/apps/repl/app/templates/edit/layout/controls/formatting.ts
index 8df76e769..5a1a5b3d1 100644
--- a/apps/repl/app/templates/edit/layout/controls/formatting.ts
+++ b/apps/repl/app/templates/edit/layout/controls/formatting.ts
@@ -49,6 +49,10 @@ const FORMATTERS: Record<FormatQP, { parser: string; plugins: PluginName[] } | u
     parser: 'ember-template-tag',
     plugins: ['babel', 'estree', 'glimmer', 'ember-template-tag'],
   },
+  'gjs|codegen': {
+    parser: 'ember-template-tag',
+    plugins: ['babel', 'estree', 'glimmer', 'ember-template-tag'],
+  },
   hbs: { parser: 'glimmer', plugins: ['glimmer'] },
   'hbs|ember': { parser: 'glimmer', plugins: ['glimmer'] },
   md: { parser: 'markdown', plugins: ['markdown'] },
diff --git a/apps/repl/public/samples/gjs-codegen-demo.gjs b/apps/repl/public/samples/gjs-codegen-demo.gjs
new file mode 100644
index 000000000..45763ac0a
--- /dev/null
+++ b/apps/repl/public/samples/gjs-codegen-demo.gjs
@@ -0,0 +1,81 @@
+// EXPERIMENTAL: this format compiles <template>s directly to DOM operations
+// (no wire format, no VM). Strict mode only.
+import Component from '@glimmer/component';
+import { tracked } from '@glimmer/tracking';
+import { trackedArray } from '@ember/reactive/collections';
+import { on } from '@ember/modifier';
+import { fn } from '@ember/helper';
+
+const shout = (text) => `${text.toUpperCase()}!`;
+
+const Card = <template>
+  <section class="card" ...attributes>
+    <h2>{{yield to="title"}}</h2>
+    {{#if (has-block "body")}}
+      {{yield to="body"}}
+    {{else}}
+      <p>(no body)</p>
+    {{/if}}
+  </section>
+</template>;
+
+class Counter extends Component {
+  @tracked count = 0;
+
+  increment = (by) => (this.count += by);
+
+  <template>
+    <button type="button" {{on "click" (fn this.increment @step)}}>
+      +{{@step}}
+    </button>
+    <output>{{this.count}}</output>
+    {{#if (eq this.count 0)}}
+      <span>Click it!</span>
+    {{else if (gt this.count 10)}}
+      <span>{{shout "that's a lot"}}</span>
+    {{/if}}
+  </template>
+}
+
+class Todos extends Component {
+  todos = trackedArray([
+    { id: 1, title: 'Compile templates to JS' },
+    { id: 2, title: 'Delete the VM?' },
+    { id: 3, title: 'Measure it' },
+  ]);
+
+  reverse = () => this.todos.reverse();
+  remove = (todo) => this.todos.splice(this.todos.indexOf(todo), 1);
+
+  <template>
+    <button type="button" {{on "click" this.reverse}}>Reverse</button>
+    <ul>
+      {{#each this.todos key="id" as |todo i|}}
+        <li>
+          {{i}}: {{todo.title}}
+          <button type="button" {{on "click" (fn this.remove todo)}}>×</button>
+        </li>
+      {{else}}
+        <li>All done</li>
+      {{/each}}
+    </ul>
+  </template>
+}
+
+<template>
+  <Card class="counter">
+    <:title>Counter</:title>
+    <:body><Counter @step={{2}} /></:body>
+  </Card>
+
+  <Card>
+    <:title>Todos</:title>
+    <:body><Todos /></:body>
+  </Card>
+
+  <Card><:title>Empty</:title></Card>
+
+  <style>
+    .card { border: 1px solid #ccc; border-radius: 0.5rem; padding: 0.5rem 1rem; margin: 1rem 0; }
+  </style>
+</template>
diff --git a/packages/ember-repl/src/services/known-modules.ts b/packages/ember-repl/src/services/known-modules.ts
index 008964c8d..a44a8e721 100644
--- a/packages/ember-repl/src/services/known-modules.ts
+++ b/packages/ember-repl/src/services/known-modules.ts
@@ -40,6 +40,13 @@ const frameworkModules = {
   '@glimmer/tracking': () => import('@glimmer/tracking'),
   '@glimmer/tracking/primitives/cache': () =>
     import('@glimmer/tracking/primitives/cache'),
+  /**
+   * EXPERIMENTAL: the runtime for the `gjs|codegen` format, where templates
+   * are compiled directly to DOM operations (no wire format, no VM).
+   * Vendored from a branch of ember.js, see the file's header.
+   */
+  // @ts-ignore
+  '@glimmer/dom': () => import('../vendor/glimmer-dom.js'),
 };
 
 const coreLibraries = {
diff --git a/packages/ember-repl/src/vendor/glimmer-dom.js b/packages/ember-repl/src/vendor/glimmer-dom.js
new file mode 100644
index 000000000..5db434514
--- /dev/null
+++ b/packages/ember-repl/src/vendor/glimmer-dom.js
@@ -0,0 +1,860 @@
+// @ts-nocheck
+/* eslint-disable */
+/**
+ * VENDORED -- do not edit.
+ *
+ * The runtime for compiled templates (`@glimmer/dom`).
+ * Built from https://github.com/NullVoxPopuli-ai-agent/ember.js/tree/claude/gallant-heisenberg-aovzyr (2b03eb8).
+ *
+ * This is an experiment: strict-mode templates compiled directly to DOM
+ * operations, with no wire format and no VM.
+ */
+
+// packages/@glimmer/dom/lib/core.ts
+import { associateDestroyableChild, destroy } from "@glimmer/destroyable";
+var Root = class {
+  constructor(owner, document) {
+    this.owner = owner;
+    this.document = document;
+  }
+  owner;
+  document;
+  #queue = [];
+  /**
+   * Schedule work that must happen after DOM is inserted
+   * (modifier install/update, component didCreate hooks).
+   */
+  schedule(fn) {
+    this.#queue.push(fn);
+  }
+  flush() {
+    while (this.#queue.length > 0) {
+      let queue = this.#queue;
+      this.#queue = [];
+      for (let fn of queue) fn();
+    }
+  }
+};
+var Block = class {
+  constructor(root, parent) {
+    this.root = root;
+    if (parent) associateDestroyableChild(parent, this);
+  }
+  root;
+  updaters = [];
+  update() {
+    let { updaters } = this;
+    for (let i = 0; i < updaters.length; i++) {
+      updaters[i]();
+    }
+  }
+};
+function marker(root) {
+  return root.document.createTextNode("");
+}
+function mount(parent, before, render2) {
+  let b = new Block(parent.root, parent);
+  let start = marker(parent.root);
+  let end = marker(parent.root);
+  let target = before.parentNode;
+  target.insertBefore(start, before);
+  target.insertBefore(render2(b), before);
+  target.insertBefore(end, before);
+  return { b, start, end };
+}
+function unmount(m) {
+  removeRange(m.start, m.end);
+  destroy(m.b);
+}
+function removeRange(first, last) {
+  let parent = first.parentNode;
+  if (!parent) return;
+  let node = first;
+  while (node) {
+    let next = node === last ? null : node.nextSibling;
+    parent.removeChild(node);
+    node = next;
+  }
+}
+function moveRange(m, before) {
+  let parent = before.parentNode;
+  let node = m.start;
+  while (node) {
+    let next = node === m.end ? null : node.nextSibling;
+    parent.insertBefore(node, before);
+    node = next;
+  }
+}
+function html(markup) {
+  return { markup, parsed: null };
+}
+function clone(b, t) {
+  let parsed = t.parsed;
+  if (parsed === null) {
+    parsed = t.parsed = b.root.document.createElement("template");
+    parsed.innerHTML = t.markup;
+  }
+  return b.root.document.importNode(parsed.content, true);
+}
+function at(node, ...path) {
+  for (let i of path) {
+    node = node.childNodes[i];
+  }
+  return node;
+}
+var Template = class {
+  constructor(render2) {
+    this.render = render2;
+  }
+  render;
+  toString() {
+    return "(compiled template)";
+  }
+};
+function template(render2) {
+  return new Template(render2);
+}
+var TEMPLATES = /* @__PURE__ */ new WeakMap();
+function setTemplate(definition, t) {
+  TEMPLATES.set(definition, t);
+  return definition;
+}
+function templateFor(definition) {
+  if (definition instanceof Template) return definition;
+  let pointer = definition;
+  while (pointer !== null && pointer !== Function.prototype && pointer !== Object.prototype) {
+    let found = TEMPLATES.get(pointer);
+    if (found) return found;
+    pointer = Object.getPrototypeOf(pointer);
+  }
+  return void 0;
+}
+
+// packages/@glimmer/dom/lib/attributes.ts
+import { registerDestructor } from "@glimmer/destroyable";
+
+// shim:@glimmer/validator/lib/tracking
+import { consumeTag, createCache, getValue, isConst, track } from "@glimmer/validator";
+
+// packages/@glimmer/dom/lib/attributes.ts
+var XHTML = "http://www.w3.org/1999/xhtml";
+var PROPERTIES = /* @__PURE__ */ new Set(["value", "checked", "selected", "indeterminate", "muted"]);
+var SANITIZED_TAGS = /* @__PURE__ */ new Set(["A", "BODY", "LINK", "IMG", "IFRAME", "BASE", "FORM"]);
+var SANITIZED_ATTRS = /* @__PURE__ */ new Set(["href", "src", "background", "action"]);
+var BAD_PROTOCOLS = /* @__PURE__ */ new Set(["javascript:", "vbscript:"]);
+function normalizeAttrValue(value) {
+  if (value === false || value === void 0 || value === null) return null;
+  if (value === true) return "";
+  if (typeof value === "function") return null;
+  if (typeof value.toString !== "function") return null;
+  return String(value);
+}
+function sanitize(element, name, value) {
+  if (value === null || !SANITIZED_TAGS.has(element.tagName) || !SANITIZED_ATTRS.has(name)) {
+    return value;
+  }
+  let protocol;
+  try {
+    protocol = new URL(value, "http://localhost").protocol;
+  } catch {
+    return value;
+  }
+  return BAD_PROTOCOLS.has(protocol) ? `unsafe:${value}` : value;
+}
+function setterFor(element, name) {
+  if (element.namespaceURI === XHTML && PROPERTIES.has(name) && name in element) {
+    return (value) => {
+      element[name] = value === null || value === void 0 ? name === "value" ? "" : false : value;
+    };
+  }
+  return (value) => {
+    let normalized = sanitize(element, name, normalizeAttrValue(value));
+    if (normalized === null) {
+      element.removeAttribute(name);
+    } else {
+      element.setAttribute(name, normalized);
+    }
+  };
+}
+function bind(b, value, setter) {
+  if (typeof value !== "function") {
+    setter(value);
+    return;
+  }
+  let cache = createCache(value);
+  let current = getValue(cache);
+  setter(current);
+  if (isConst(cache)) return;
+  b.updaters.push(() => {
+    let next = getValue(cache);
+    if (next !== current) {
+      current = next;
+      setter(next);
+    }
+  });
+}
+var CLASSES = /* @__PURE__ */ new WeakMap();
+function classPart(b, element, value) {
+  let state = CLASSES.get(element);
+  if (!state) {
+    state = { parts: [] };
+    let existing = element.getAttribute("class");
+    if (existing) state.parts.push(existing);
+    CLASSES.set(element, state);
+  }
+  let { parts } = state;
+  let index = parts.length;
+  parts.push("");
+  bind(b, value, (next) => {
+    parts[index] = normalizeAttrValue(next) ?? "";
+    let className = parts.filter(Boolean).join(" ");
+    if (className) {
+      element.setAttribute("class", className);
+    } else {
+      element.removeAttribute("class");
+    }
+  });
+}
+function attr(b, element, name, value) {
+  if (name === "class") {
+    classPart(b, element, value);
+  } else {
+    bind(b, value, setterFor(element, name));
+  }
+}
+function splat(b, element, ctx) {
+  ctx.attrs?.(b, element);
+}
+function listen(b, element, eventName, handler, options) {
+  let cache = createCache(handler);
+  let listener = (event) => {
+    let fn = getValue(cache);
+    if (typeof fn === "function") {
+      return fn(event);
+    }
+    throw new Error(
+      `You must pass a function as the second argument to the \`on\` modifier; you passed ${String(fn)}.`
+    );
+  };
+  element.addEventListener(eventName, listener, options);
+  registerDestructor(b, () => {
+    element.removeEventListener(eventName, listener, options);
+  });
+}
+
+// shim:@glimmer/manager/lib/internal/api
+import { getInternalComponentManager, getInternalHelperManager, getInternalModifierManager } from "@glimmer/manager";
+
+// packages/@glimmer/dom/lib/invoke.ts
+import { associateDestroyableChild as associateDestroyableChild3, registerDestructor as registerDestructor2 } from "@glimmer/destroyable";
+
+// shim:@glimmer/reference/lib/reference
+import { createComputeRef, valueForRef } from "@glimmer/reference";
+
+// packages/@glimmer/dom/lib/managers.ts
+import { associateDestroyableChild as associateDestroyableChild2, destroy as destroy2 } from "@glimmer/destroyable";
+
+// shim:@glimmer/validator/lib/validators
+import { createTag, dirtyTag, updateTag, validateTag, valueForTag } from "@glimmer/validator";
+
+// packages/@glimmer/dom/lib/managers.ts
+function capture(named, positional) {
+  let capturedNamed = /* @__PURE__ */ Object.create(null);
+  if (named) {
+    for (let key of Object.keys(named)) {
+      capturedNamed[key] = createComputeRef(named[key]);
+    }
+  }
+  let capturedPositional = (positional ?? []).map((thunk) => createComputeRef(thunk));
+  return {
+    named: capturedNamed,
+    positional: capturedPositional
+  };
+}
+function resolveHelper(definition) {
+  let manager = getInternalHelperManager(definition);
+  return typeof manager === "function" ? manager : manager.getHelper(definition);
+}
+function instantiateHelper(b, definition, args) {
+  let ref = resolveHelper(definition)(args, b.root.owner);
+  associateDestroyableChild2(b, ref);
+  return ref;
+}
+function helper(b, definition, positional, named) {
+  let ref = instantiateHelper(b, definition, capture(named, positional));
+  return () => valueForRef(ref);
+}
+function helperDyn(b, definition, positional, named) {
+  let args = capture(named, positional);
+  let definitionCache = createCache(definition);
+  let current;
+  let ref = null;
+  return () => {
+    let next = getValue(definitionCache);
+    if (next !== current || ref === null) {
+      if (ref !== null) destroy2(ref);
+      current = next;
+      ref = instantiateHelper(b, next, args);
+    }
+    return valueForRef(ref);
+  };
+}
+function modifier(b, element, definition, positional, named) {
+  let manager = getInternalModifierManager(definition);
+  let state = manager.create(
+    b.root.owner,
+    element,
+    definition,
+    capture(named, positional)
+  );
+  let destroyable = manager.getDestroyable(state);
+  if (destroyable) associateDestroyableChild2(b, destroyable);
+  let tag = manager.getTag(state);
+  if (tag === null) {
+    b.root.schedule(() => {
+      manager.install(state);
+    });
+    return;
+  }
+  let lastRevision = null;
+  let run = (hook) => {
+    updateTag(
+      tag,
+      track(() => {
+        hook(state);
+      })
+    );
+    consumeTag(tag);
+    lastRevision = valueForTag(tag);
+  };
+  b.root.schedule(() => {
+    run((s) => {
+      manager.install(s);
+    });
+  });
+  b.updaters.push(() => {
+    consumeTag(tag);
+    if (lastRevision === null || validateTag(tag, lastRevision)) return;
+    lastRevision = null;
+    b.root.schedule(() => {
+      run((s) => {
+        manager.update(s);
+      });
+    });
+  });
+}
+
+// packages/@glimmer/dom/lib/invoke.ts
+var Curried = class {
+  constructor(definition, named) {
+    this.definition = definition;
+    this.named = named;
+  }
+  definition;
+  named;
+};
+function curry(definition, named) {
+  if (!definition) return null;
+  return new Curried(definition, named ?? {});
+}
+function isComponentDefinition(value) {
+  if (value instanceof Template || value instanceof Curried) return true;
+  if (typeof value !== "object" && typeof value !== "function" || value === null) return false;
+  if (templateFor(value)) return true;
+  return getInternalComponentManager(value, true) !== null;
+}
+var vmFallback = null;
+function setVMFallback(fallback) {
+  vmFallback = fallback;
+}
+function describe(definition) {
+  return typeof definition === "function" ? definition.name || "(anonymous component)" : Object.prototype.toString.call(definition);
+}
+function argsFor(captured) {
+  let args = /* @__PURE__ */ Object.create(null);
+  for (let key of Object.keys(captured.named)) {
+    let ref = captured.named[key];
+    Object.defineProperty(args, key, { enumerable: true, get: () => valueForRef(ref) });
+  }
+  return args;
+}
+function island(b, definition, named) {
+  if (!vmFallback) {
+    throw new Error(
+      `${describe(definition)} does not have a compiled template, and there is no VM fallback registered to render it.`
+    );
+  }
+  let args = /* @__PURE__ */ Object.create(null);
+  for (let key of Object.keys(named)) {
+    Object.defineProperty(args, key, { enumerable: true, get: named[key] });
+  }
+  let element = b.root.document.createElement("glimmer-island");
+  element.style.display = "contents";
+  let result = vmFallback(definition, element, b.root.owner, args);
+  registerDestructor2(b, () => {
+    result.destroy();
+  });
+  return element;
+}
+function instantiate(b, definition, named, blocks, attrs) {
+  while (definition instanceof Curried) {
+    named = { ...definition.named, ...named };
+    definition = definition.definition;
+  }
+  let compiled = templateFor(definition);
+  if (!compiled) return island(b, definition, named);
+  let captured = capture(named, null);
+  let args = argsFor(captured);
+  if (compiled === definition) {
+    return compiled.render(b, { self: void 0, args, blocks, attrs });
+  }
+  let manager = getInternalComponentManager(definition);
+  if (!("getDelegateFor" in manager)) {
+    throw new Error(
+      `Compiled templates can only be used with components that have a custom component manager (like @glimmer/component). ${describe(definition)} does not.`
+    );
+  }
+  let state = manager.create(b.root.owner, definition, { capture: () => captured });
+  let self = valueForRef(manager.getSelf(state));
+  let destroyable = manager.getDestroyable(state);
+  if (destroyable) associateDestroyableChild3(b, destroyable);
+  b.root.schedule(() => {
+    manager.didCreate(state);
+  });
+  return compiled.render(b, { self, args, blocks, attrs });
+}
+function invoke(b, anchor, definition, named, blocks, attrs) {
+  let m = mount(b, anchor, (child) => instantiate(child, definition, named, blocks, attrs));
+  b.updaters.push(() => {
+    m.b.update();
+  });
+}
+function invokeDyn(b, anchor, definition, named, blocks, attrs) {
+  let cache = createCache(definition);
+  let current = getValue(cache);
+  let render2 = (value) => value ? mount(b, anchor, (child) => instantiate(child, value, named, blocks, attrs)) : null;
+  let m = render2(current);
+  b.updaters.push(() => {
+    let next = getValue(cache);
+    if (next === current) {
+      m?.b.update();
+      return;
+    }
+    if (m) unmount(m);
+    current = next;
+    m = render2(next);
+  });
+}
+
+// packages/@glimmer/dom/lib/values.ts
+import { getPath as globalGetPath, getProp, toBool } from "@glimmer/global-context";
+function get(obj, ...keys) {
+  for (let key of keys) {
+    if (obj === null || obj === void 0) return void 0;
+    obj = getProp(obj, key);
+  }
+  return obj;
+}
+function getPath(obj, path) {
+  if (obj === null || obj === void 0 || path === null || path === void 0) return void 0;
+  return globalGetPath(obj, String(path));
+}
+function bool(value) {
+  return toBool(value);
+}
+function isEmpty(value) {
+  return value === null || value === void 0 || typeof value.toString !== "function";
+}
+function str(value) {
+  return isEmpty(value) ? "" : String(value);
+}
+function and(...values) {
+  let last;
+  for (let value of values) {
+    last = value();
+    if (!toBool(last)) return last;
+  }
+  return last;
+}
+function or(...values) {
+  let last;
+  for (let value of values) {
+    last = value();
+    if (toBool(last)) return last;
+  }
+  return last;
+}
+function memo(fn) {
+  let cache = createCache(fn);
+  return () => getValue(cache);
+}
+function log(...values) {
+  console.log(...values);
+  return void 0;
+}
+function entries(obj) {
+  if (obj === null || obj === void 0) return [];
+  if (obj instanceof Map) return Array.from(obj.entries());
+  return Object.keys(obj).map((key) => [key, get(obj, key)]);
+}
+function hasBlock(ctx, name = "default") {
+  return Boolean(ctx.blocks?.[name]);
+}
+function hasBlockParams(ctx, name = "default") {
+  let block2 = ctx.blocks?.[name];
+  return block2 ? block2.length > 1 : false;
+}
+
+// packages/@glimmer/dom/lib/content.ts
+var MAY_CALL = 1;
+var TRUSTING = 2;
+function isSafeString(value) {
+  return typeof value === "object" && value !== null && typeof value.toHTML === "function";
+}
+function isNode(value) {
+  return typeof value === "object" && value !== null && typeof value.nodeType === "number";
+}
+function kindOf(value, flags) {
+  if (typeof value === "string") return flags & TRUSTING ? 1 /* html */ : 0 /* text */;
+  if (value === null || value === void 0) return 0 /* text */;
+  if (typeof value !== "object" && typeof value !== "function") return 0 /* text */;
+  if (isSafeString(value)) return 1 /* html */;
+  if (isNode(value)) return 2 /* node */;
+  if (isComponentDefinition(value)) return 3 /* component */;
+  return 0 /* text */;
+}
+function isHelperLike(value) {
+  if (isComponentDefinition(value)) return false;
+  if (typeof value === "function") return true;
+  return typeof value === "object" && value !== null && getInternalHelperManager(value, true) !== null;
+}
+function insertNodes(parent, before, nodes) {
+  let doc = parent.ownerDocument ?? parent;
+  if (nodes.nodeType === 11) {
+    if (!nodes.firstChild) nodes.appendChild(doc.createTextNode(""));
+    let first = nodes.firstChild;
+    let last = nodes.lastChild;
+    parent.insertBefore(nodes, before);
+    return { first, last, text: null, mounted: null };
+  }
+  parent.insertBefore(nodes, before);
+  return { first: nodes, last: nodes, text: null, mounted: null };
+}
+function render(b, parent, before, kind, value, flags) {
+  let doc = b.root.document;
+  switch (kind) {
+    case 0 /* text */: {
+      let text = doc.createTextNode(str(value));
+      parent.insertBefore(text, before);
+      return { first: text, last: text, text, mounted: null };
+    }
+    case 1 /* html */: {
+      let t = doc.createElement("template");
+      t.innerHTML = flags & TRUSTING && !isSafeString(value) ? str(value) : value.toHTML();
+      return insertNodes(parent, before, t.content);
+    }
+    case 2 /* node */:
+      return insertNodes(parent, before, value);
+    case 3 /* component */: {
+      let mounted = mount(
+        b,
+        before,
+        (child) => instantiate(child, value, {}, null, null)
+      );
+      return { first: mounted.start, last: mounted.end, text: null, mounted };
+    }
+  }
+}
+function clear(slot) {
+  if (slot.mounted) {
+    unmount(slot.mounted);
+  } else {
+    removeRange(slot.first, slot.last);
+  }
+}
+function content(b, anchor, fn, flags = 0) {
+  if (flags & MAY_CALL) {
+    let definition = fn();
+    if (isHelperLike(definition)) fn = helper(b, definition, null, null);
+  }
+  let cache = createCache(fn);
+  let value = getValue(cache);
+  let kind = kindOf(value, flags);
+  let parent = anchor.parentNode;
+  let slot = render(b, parent, anchor, kind, value, flags);
+  parent.removeChild(anchor);
+  if (isConst(cache) && kind !== 3 /* component */) return;
+  b.updaters.push(() => {
+    let next = getValue(cache);
+    if (next === value) {
+      slot.mounted?.b.update();
+      return;
+    }
+    let nextKind = kindOf(next, flags);
+    if (kind === 0 /* text */ && nextKind === 0 /* text */ && slot.text) {
+      slot.text.data = str(next);
+      value = next;
+      return;
+    }
+    let nextSlot = render(b, slot.first.parentNode, slot.first, nextKind, next, flags);
+    clear(slot);
+    slot = nextSlot;
+    kind = nextKind;
+    value = next;
+  });
+}
+function appendCall(b, anchor, definition, isStatic, positional, named, flags = 0) {
+  let value = isStatic ? definition : definition();
+  if (isComponentDefinition(value)) {
+    if (positional) {
+      throw new Error("positional arguments to components are not supported yet");
+    }
+    if (isStatic) {
+      invoke(b, anchor, value, named ?? {}, null, null);
+    } else {
+      invokeDyn(b, anchor, definition, named ?? {}, null, null);
+    }
+    return;
+  }
+  let result = isStatic ? helper(b, value, positional, named) : helperDyn(b, definition, positional, named);
+  content(b, anchor, result, flags);
+}
+
+// shim:@glimmer/reference/lib/iterable
+import { createIteratorRef } from "@glimmer/reference";
+
+// shim:@glimmer/validator/lib/meta
+import { tagFor } from "@glimmer/validator";
+
+// packages/@glimmer/dom/lib/control-flow.ts
+function when(b, anchor, condition, consequent, alternate) {
+  let cache = createCache(condition);
+  let current = Boolean(getValue(cache));
+  let render2 = (value) => {
+    let fn = value ? consequent : alternate;
+    return fn ? mount(b, anchor, fn) : null;
+  };
+  let m = render2(current);
+  b.updaters.push(() => {
+    let next = Boolean(getValue(cache));
+    if (next === current) {
+      m?.b.update();
+      return;
+    }
+    if (m) unmount(m);
+    current = next;
+    m = render2(next);
+  });
+}
+function cell(initial) {
+  let tag = createTag();
+  let value = initial;
+  return {
+    read: () => {
+      consumeTag(tag);
+      return value;
+    },
+    set(next) {
+      if (next !== value) {
+        value = next;
+        dirtyTag(tag);
+      }
+    }
+  };
+}
+function each(b, anchor, list, key, item, inverse) {
+  let listRef = createComputeRef(() => {
+    let value = list();
+    if (typeof value === "object" && value !== null) consumeTag(tagFor(value, "[]"));
+    return value;
+  });
+  let iteratorRef = createIteratorRef(listRef, key ?? "@identity");
+  let rows = [];
+  let byKey = /* @__PURE__ */ new Map();
+  let inverseMounted = null;
+  let lastIterator = null;
+  let sync = () => {
+    let iterator = valueForRef(iteratorRef);
+    if (iterator === lastIterator) {
+      for (let row of rows) row.m?.b.update();
+      inverseMounted?.b.update();
+      return;
+    }
+    lastIterator = iterator;
+    let nextRows = [];
+    let nextByKey = /* @__PURE__ */ new Map();
+    for (let entry = iterator.next(); entry !== null; entry = iterator.next()) {
+      let row = byKey.get(entry.key);
+      if (row) {
+        row.value.set(entry.value);
+        row.index.set(entry.memo);
+      } else {
+        row = { value: cell(entry.value), index: cell(entry.memo), m: null };
+      }
+      nextByKey.set(entry.key, row);
+      nextRows.push(row);
+    }
+    for (let [k, row] of byKey) {
+      if (nextByKey.get(k) !== row && row.m) unmount(row.m);
+    }
+    let before = anchor;
+    for (let i = nextRows.length - 1; i >= 0; i--) {
+      let row = nextRows[i];
+      if (row.m === null) {
+        let { value, index } = row;
+        row.m = mount(b, before, (child) => item(child, value.read, index.read));
+      } else {
+        if (row.m.end.nextSibling !== before) moveRange(row.m, before);
+        row.m.b.update();
+      }
+      before = row.m.start;
+    }
+    rows = nextRows;
+    byKey = nextByKey;
+    if (rows.length === 0 && inverse && !inverseMounted) {
+      inverseMounted = mount(b, anchor, inverse);
+    } else if (rows.length > 0 && inverseMounted) {
+      unmount(inverseMounted);
+      inverseMounted = null;
+    }
+  };
+  sync();
+  b.updaters.push(sync);
+}
+function block(b, anchor, fn, params) {
+  let m = mount(b, anchor, (child) => fn(child, ...params));
+  b.updaters.push(() => {
+    m.b.update();
+  });
+}
+function yieldTo(b, anchor, ctx, name, params) {
+  let fn = ctx.blocks?.[name] ?? (name === "else" ? ctx.blocks?.["inverse"] : void 0);
+  if (fn) block(b, anchor, fn, params);
+}
+function scope(b, anchor, fn) {
+  block(b, anchor, fn, []);
+}
+function inElement(b, destination, append, fn) {
+  let cache = createCache(destination);
+  let current = null;
+  let m = null;
+  let end = null;
+  let render2 = (target) => {
+    current = target;
+    if (!target) return;
+    if (!append) target.innerHTML = "";
+    end = marker(b.root);
+    target.appendChild(end);
+    m = mount(b, end, fn);
+  };
+  render2(getValue(cache));
+  b.updaters.push(() => {
+    let next = getValue(cache);
+    if (next === current) {
+      m?.b.update();
+      return;
+    }
+    if (m) unmount(m);
+    if (end) removeRange(end, end);
+    m = null;
+    end = null;
+    render2(next);
+  });
+}
+
+// packages/@glimmer/dom/lib/render.ts
+import { destroy as destroy3 } from "@glimmer/destroyable";
+
+// shim:@ember/-internals/glimmer/lib/base-renderer
+import { renderComponent } from "@ember/renderer";
+
+// packages/@glimmer/dom/lib/render.ts
+import { _backburner } from "@ember/runloop";
+setVMFallback((definition, into, owner, args) => renderComponent(definition, { into, owner, args }));
+function renderComponent2(component, {
+  into,
+  owner = {},
+  args
+}) {
+  let root = new Root(owner, into.ownerDocument);
+  let b = new Block(root, null);
+  let named = {};
+  if (args) {
+    for (let key of Object.keys(args)) named[key] = () => args[key];
+  }
+  into.innerHTML = "";
+  let end = marker(root);
+  into.appendChild(end);
+  let tag;
+  let revision;
+  let destroyed = false;
+  let pass = (fn) => {
+    tag = track(() => {
+      fn();
+      root.flush();
+    });
+    revision = valueForTag(tag);
+  };
+  pass(() => {
+    let m = mount(b, end, (child) => instantiate(child, component, named, null, null));
+    b.updaters.push(() => {
+      m.b.update();
+    });
+  });
+  let rerender = () => {
+    if (destroyed || validateTag(tag, revision)) return;
+    pass(() => {
+      b.update();
+    });
+  };
+  _backburner.on("end", rerender);
+  return {
+    rerender,
+    destroy() {
+      if (destroyed) return;
+      destroyed = true;
+      _backburner.off("end", rerender);
+      removeRange(into.firstChild, end);
+      destroy3(b);
+    }
+  };
+}
+export {
+  MAY_CALL,
+  TRUSTING,
+  Template,
+  and,
+  appendCall,
+  at,
+  attr,
+  bool,
+  clone,
+  content,
+  curry,
+  each,
+  entries,
+  get,
+  getPath,
+  hasBlock,
+  hasBlockParams,
+  helper,
+  helperDyn,
+  html,
+  inElement,
+  invoke,
+  invokeDyn,
+  listen,
+  log,
+  memo,
+  modifier,
+  or,
+  renderComponent2 as renderComponent,
+  scope,
+  setTemplate,
+  setVMFallback,
+  splat,
+  str,
+  template,
+  when,
+  yieldTo
+};
diff --git a/packages/repl-sdk/src/compilers/ember.js b/packages/repl-sdk/src/compilers/ember.js
index cdb0b704b..672d8867a 100644
--- a/packages/repl-sdk/src/compilers/ember.js
+++ b/packages/repl-sdk/src/compilers/ember.js
@@ -107,24 +107,45 @@ function onUnhandled(e, handle) {
   handle(reason);
 }
 
+const gjsCodemirror = {
+  lang: async () => {
+    const { gjs } = await import('codemirror-lang-glimmer-js');
+
+    return gjs();
+  },
+};
+
 /**
- * @type {CompilerConfig}
+ * `gjs` doubles as the config for its flavors (`gjs|codegen`).
+ *
+ * @type {CompilerConfig & { codegen: CompilerConfig }}
  */
 export const gjs = {
   resolve,
   onUnhandled,
-  codemirror: {
-    lang: async () => {
-      const { gjs } = await import('codemirror-lang-glimmer-js');
-
-      return gjs();
-    },
-  },
+  codemirror: gjsCodemirror,
   compiler: async (...args) => {
     const gjs = await import('./ember/gjs.js');
 
     return gjs.compiler(...args);
   },
+
+  /**
+   * EXPERIMENTAL: strict-mode templates compiled directly to DOM operations,
+   * with no wire format and no VM.
+   *
+   * The host must provide `@glimmer/dom` (ember-repl does).
+   */
+  codegen: {
+    resolve,
+    onUnhandled,
+    codemirror: gjsCodemirror,
+    compiler: async (config, api) => {
+      const gjs = await import('./ember/gjs.js');
+
+      return gjs.compiler(config, api, { codegen: true });
+    },
+  },
 };
 
 /**
diff --git a/packages/repl-sdk/src/compilers/ember/gjs.js b/packages/repl-sdk/src/compilers/ember/gjs.js
index c3a350ee7..dee8f19eb 100644
--- a/packages/repl-sdk/src/compilers/ember/gjs.js
+++ b/packages/repl-sdk/src/compilers/ember/gjs.js
@@ -55,12 +55,17 @@ const buildDependencies = [
  * gjs and gts share one pipeline.
  * gts adds the babel typescript plugin, which only strips types.
  *
+ * `codegen` is EXPERIMENTAL: templates are compiled directly to DOM operations
+ * (no wire format, no VM), and rendered with the runtime from `@glimmer/dom`.
+ * See https://github.com/NullVoxPopuli-ai-agent/ember.js/tree/claude/gallant-heisenberg-aovzyr/packages/@glimmer/dom
+ *
  * @param {Parameters<CompilerFactory>[0]} config
  * @param {Parameters<CompilerFactory>[1]} api
- * @param {{ typescript?: boolean }} [flags]
+ * @param {{ typescript?: boolean; codegen?: boolean }} [flags]
  */
 export async function compiler(config, api, flags = {}) {
   const typescript = flags.typescript ?? false;
+  const codegen = flags.codegen ?? false;
   const ext = typescript ? 'ts' : 'js';
   const filename = `dynamic-repl.${ext}`;
 
@@ -85,6 +90,26 @@ export async function compiler(config, api, flags = {}) {
 
   const babel = 'availablePlugins' in _babel ? _babel : _babel.default;
 
+  /**
+   * @type {unknown[]}
+   */
+  const templatePlugin = codegen
+    ? [
+        (await import('./vendor/codegen-compiler.js')).codegenBabelPlugin,
+        // the parser that ships with ember-source
+        { preprocess: compiler._preprocess },
+      ]
+    : [
+        emberTemplateCompilation,
+        {
+          compiler,
+          transforms: [
+            // ...macros.templateMacros
+          ],
+          targetFormat: 'wire',
+        },
+      ];
+
   // let macros = embroiderMacros.buildMacros();
 
   /**
@@ -111,16 +136,7 @@ export async function compiler(config, api, flags = {}) {
     return babel.transformAsync(text, {
       filename,
       plugins: typePlugins.concat([
-        [
-          emberTemplateCompilation,
-          {
-            compiler,
-            transforms: [
-              // ...macros.templateMacros
-            ],
-            targetFormat: 'wire',
-          },
-        ],
+        templatePlugin,
         [
           // @ts-ignore - we don't care about types here..
           decoratorTransforms,
@@ -200,7 +216,9 @@ export async function compiler(config, api, flags = {}) {
 
       element.setAttribute(attribute, '');
 
-      const { renderComponent } = await compiler.tryResolve('@ember/renderer');
+      const { renderComponent } = await compiler.tryResolve(
+        codegen ? '@glimmer/dom' : '@ember/renderer'
+      );
 
       const owner = makeOwner(config.owner);
       const args = /** @type {Record<string, unknown> | undefined} */ (
diff --git a/packages/repl-sdk/src/compilers/ember/vendor/codegen-compiler.js b/packages/repl-sdk/src/compilers/ember/vendor/codegen-compiler.js
new file mode 100644
index 000000000..253a33ccd
--- /dev/null
+++ b/packages/repl-sdk/src/compilers/ember/vendor/codegen-compiler.js
@@ -0,0 +1,900 @@
+// @ts-nocheck
+/* eslint-disable */
+/**
+ * VENDORED -- do not edit.
+ *
+ * The template compiler for the codegen flavor (babel plugin + code generator).
+ * Built from https://github.com/NullVoxPopuli-ai-agent/ember.js/tree/claude/gallant-heisenberg-aovzyr (2b03eb8).
+ *
+ * This is an experiment: strict-mode templates compiled directly to DOM
+ * operations, with no wire format and no VM.
+ */
+
+// packages/@glimmer/compiler/lib/codegen/generate.ts
+var CodegenError = class extends Error {
+  constructor(message, node) {
+    let loc = node?.loc;
+    let where = loc?.startPosition ? ` (line ${loc.startPosition.line}, column ${loc.startPosition.column})` : "";
+    super(`${message}${where}`);
+    this.name = "CodegenError";
+  }
+};
+var VOID_ELEMENTS = /* @__PURE__ */ new Set([
+  "area",
+  "base",
+  "br",
+  "col",
+  "command",
+  "embed",
+  "hr",
+  "img",
+  "input",
+  "keygen",
+  "link",
+  "meta",
+  "param",
+  "source",
+  "track",
+  "wbr"
+]);
+var KEYWORDS = /* @__PURE__ */ new Set([
+  "action",
+  "component",
+  "debugger",
+  "each",
+  "each-in",
+  "has-block",
+  "has-block-params",
+  "helper",
+  "if",
+  "in-element",
+  "let",
+  "log",
+  "modifier",
+  "mount",
+  "mut",
+  "outlet",
+  "readonly",
+  "unbound",
+  "unless",
+  "yield"
+]);
+var AUTO_IMPORTED = {
+  and: "@ember/helper",
+  array: "@ember/helper",
+  element: "@ember/helper",
+  eq: "@ember/helper",
+  fn: "@ember/helper",
+  gt: "@ember/helper",
+  gte: "@ember/helper",
+  hash: "@ember/helper",
+  lt: "@ember/helper",
+  lte: "@ember/helper",
+  neq: "@ember/helper",
+  not: "@ember/helper",
+  on: "@ember/modifier",
+  or: "@ember/helper"
+};
+var SPECIALIZED = {
+  "@ember/helper": /* @__PURE__ */ new Set([
+    "and",
+    "array",
+    "concat",
+    "eq",
+    "fn",
+    "get",
+    "gt",
+    "gte",
+    "hash",
+    "lt",
+    "lte",
+    "neq",
+    "not",
+    "or"
+  ]),
+  "@ember/modifier": /* @__PURE__ */ new Set(["on"])
+};
+var COMPARISONS = {
+  eq: "===",
+  neq: "!==",
+  gt: ">",
+  gte: ">=",
+  lt: "<",
+  lte: "<="
+};
+var IDENTIFIER = /^[A-Za-z_$][\w$]*$/u;
+var q = (value) => JSON.stringify(value);
+function key(name) {
+  return IDENTIFIER.test(name) ? name : q(name);
+}
+function prop(name) {
+  return IDENTIFIER.test(name) ? `.${name}` : `[${q(name)}]`;
+}
+function escapeText(text) {
+  return text.replace(/&/gu, "&amp;").replace(/</gu, "&lt;").replace(/>/gu, "&gt;");
+}
+function escapeAttr(text) {
+  return text.replace(/&/gu, "&amp;").replace(/"/gu, "&quot;");
+}
+var Scope = class _Scope {
+  constructor(parent) {
+    this.parent = parent;
+  }
+  parent;
+  #names = /* @__PURE__ */ new Map();
+  bind(name, js) {
+    this.#names.set(name, js);
+  }
+  lookup(name) {
+    return this.#names.get(name) ?? this.parent?.lookup(name);
+  }
+  child() {
+    return new _Scope(this);
+  }
+};
+var Generator = class {
+  constructor(options) {
+    this.options = options;
+  }
+  options;
+  #uid = 0;
+  #hoisted = [];
+  #html = /* @__PURE__ */ new Map();
+  get hoisted() {
+    return this.#hoisted;
+  }
+  uid(prefix) {
+    return `$_${this.options.prefix ?? ""}${prefix}${++this.#uid}`;
+  }
+  rt(name) {
+    return this.options.runtime(name);
+  }
+  template(ast) {
+    let scope = new Scope(null);
+    let body = this.body(ast.body, scope);
+    return `${this.rt("template")}(($_b, $_ctx) => {
+const $_s = $_ctx.self, $_a = $_ctx.args;
+${body}
+})`;
+  }
+  /////////////////////////////////////////////////////////////////////////
+  // Blocks of content
+  /////////////////////////////////////////////////////////////////////////
+  /**
+   * Generate a function body that renders `statements`, and returns the DOM.
+   */
+  body(statements, scope) {
+    let body = { lines: [], scope };
+    let ops = [];
+    let markup = this.html(statements, [], ops, body);
+    let root = this.uid("r");
+    body.lines.push(`const ${root} = ${this.rt("clone")}($_b, ${this.hoistHTML(markup)});`);
+    let refs = ops.map((op) => {
+      let ref = this.uid("n");
+      body.lines.push(`const ${ref} = ${this.rt("at")}(${[root, ...op.path].join(", ")});`);
+      return ref;
+    });
+    ops.forEach((op, i) => {
+      let ref = refs[i];
+      if (op.kind === "element") {
+        this.elementOps(op.node, ref, body);
+      } else {
+        this.slot(op.node, ref, body);
+      }
+    });
+    body.lines.push(`return ${root};`);
+    return body.lines.join("\n");
+  }
+  blockFn(block, scope) {
+    if (!block) return "undefined";
+    return this.blockFnWith(block.body, block.blockParams, scope);
+  }
+  blockFnWith(statements, params, scope, bindParam) {
+    let inner = scope.child();
+    let names = params.map((name, i) => {
+      let id = this.uid("p");
+      if (bindParam) {
+        bindParam(id, i, inner);
+      } else {
+        inner.bind(name, `${id}()`);
+      }
+      return id;
+    });
+    return `($_b${names.map((n) => `, ${n}`).join("")}) => {
+${this.body(statements, inner)}
+}`;
+  }
+  hoistHTML(markup) {
+    let existing = this.#html.get(markup);
+    if (existing) return existing;
+    let id = this.uid("t");
+    this.#hoisted.push(`const ${id} = ${this.rt("html")}(${q(markup)});`);
+    this.#html.set(markup, id);
+    return id;
+  }
+  /**
+   * Build the static HTML for a list of statements, recording the dynamic
+   * parts (and the child-index path to their node) in `ops`.
+   */
+  html(statements, path, ops, body) {
+    let out = "";
+    let index = 0;
+    let text = null;
+    let flushText = () => {
+      if (text) {
+        out += escapeText(text);
+        index++;
+      }
+      text = null;
+    };
+    for (let statement of statements) {
+      switch (statement.type) {
+        case "TextNode":
+          text = (text ?? "") + statement.chars;
+          break;
+        case "MustacheCommentStatement":
+          break;
+        case "CommentStatement":
+          flushText();
+          out += `<!--${statement.value}-->`;
+          index++;
+          break;
+        case "MustacheStatement": {
+          let literal = staticText(statement);
+          if (literal !== null) {
+            text = (text ?? "") + literal;
+            break;
+          }
+          flushText();
+          out += "<!>";
+          ops.push({ kind: "slot", path: [...path, index++], node: statement });
+          break;
+        }
+        case "BlockStatement":
+          flushText();
+          out += "<!>";
+          ops.push({ kind: "slot", path: [...path, index++], node: statement });
+          break;
+        case "ElementNode":
+          flushText();
+          if (this.isComponent(statement, body.scope)) {
+            out += "<!>";
+            ops.push({ kind: "slot", path: [...path, index++], node: statement });
+          } else {
+            out += this.element(statement, [...path, index++], ops, body);
+          }
+          break;
+      }
+    }
+    flushText();
+    return out;
+  }
+  element(node, path, ops, body) {
+    let { tag } = node;
+    let out = `<${tag}`;
+    let dynamic = node.modifiers.length > 0;
+    let splatted = false;
+    for (let attr of node.attributes) {
+      if (attr.name === "...attributes") {
+        splatted = dynamic = true;
+      } else if (attr.value.type === "TextNode" && !splatted) {
+        out += attr.value.chars === "" ? ` ${attr.name}` : ` ${attr.name}="${escapeAttr(attr.value.chars)}"`;
+      } else {
+        dynamic = true;
+      }
+    }
+    out += ">";
+    if (dynamic) ops.push({ kind: "element", path, node });
+    if (VOID_ELEMENTS.has(tag)) return out;
+    let children = this.html(node.children, path, ops, body);
+    if ((tag === "pre" || tag === "textarea" || tag === "listing") && children.startsWith("\n")) {
+      children = `
+${children}`;
+    }
+    return `${out}${children}</${tag}>`;
+  }
+  isComponent(node, scope) {
+    let { head, tail } = node.path;
+    if (head.type !== "VarHead") return true;
+    if (tail.length > 0) return true;
+    if (scope.lookup(head.name) !== void 0) return true;
+    if (this.options.isLexical(head.name)) return true;
+    return /^[A-Z]/u.test(head.name);
+  }
+  /////////////////////////////////////////////////////////////////////////
+  // Elements
+  /////////////////////////////////////////////////////////////////////////
+  elementOps(node, element, body) {
+    let splatted = false;
+    for (let attr of node.attributes) {
+      if (attr.name === "...attributes") {
+        splatted = true;
+        body.lines.push(`${this.rt("splat")}($_b, ${element}, $_ctx);`);
+      } else if (attr.value.type === "TextNode") {
+        if (splatted) {
+          body.lines.push(
+            `${this.rt("attr")}($_b, ${element}, ${q(attr.name)}, ${q(attr.value.chars)});`
+          );
+        }
+      } else {
+        body.lines.push(
+          `${this.rt("attr")}($_b, ${element}, ${q(attr.name)}, () => ${this.attrValue(attr.value, body)});`
+        );
+      }
+    }
+    for (let modifier of node.modifiers) {
+      this.modifier(modifier, element, body);
+    }
+  }
+  attrValue(value, body) {
+    switch (value.type) {
+      case "TextNode":
+        return q(value.chars);
+      case "MustacheStatement":
+        return this.mustacheValue(value, body);
+      case "ConcatStatement":
+        return `(${[
+          '""',
+          ...value.parts.map(
+            (part) => part.type === "TextNode" ? q(part.chars) : `${this.rt("str")}(${this.mustacheValue(part, body)})`
+          )
+        ].join(" + ")})`;
+    }
+  }
+  modifier(node, element, body) {
+    let builtin = this.builtin(node.path, body.scope);
+    if (builtin === "on") {
+      let [event, handler] = node.params;
+      if (!event || !handler) {
+        throw new CodegenError("`on` requires an event name and a handler", node);
+      }
+      let options = node.hash.pairs.length ? `, { ${node.hash.pairs.map((p) => `${key(p.key)}: ${this.expr(p.value, body)}`).join(", ")} }` : "";
+      body.lines.push(
+        `${this.rt("listen")}($_b, ${element}, ${this.expr(event, body)}, () => ${this.expr(handler, body)}${options});`
+      );
+      return;
+    }
+    if (builtin !== null) {
+      throw new CodegenError(`\`${builtin}\` cannot be used as a modifier`, node);
+    }
+    body.lines.push(
+      `${this.rt("modifier")}($_b, ${element}, ${this.expr(node.path, body)}, ${this.positional(
+        node.params,
+        body
+      )}, ${this.named(node.hash, body)});`
+    );
+  }
+  /////////////////////////////////////////////////////////////////////////
+  // Dynamic content
+  /////////////////////////////////////////////////////////////////////////
+  slot(node, anchor, body) {
+    switch (node.type) {
+      case "ElementNode": {
+        this.componentElement(node, anchor, body);
+        return;
+      }
+      case "MustacheStatement": {
+        this.append(node, anchor, body);
+        return;
+      }
+      case "BlockStatement": {
+        this.block(node, anchor, body);
+        return;
+      }
+    }
+  }
+  append(node, anchor, body) {
+    let { path, params, hash } = node;
+    let flags = node.trusting ? 2 : 0;
+    if (path.type !== "PathExpression") {
+      body.lines.push(
+        `${this.rt("content")}($_b, ${anchor}, () => ${this.mustacheValue(node, body)}, ${flags});`
+      );
+      return;
+    }
+    let builtin = this.builtin(path, body.scope);
+    switch (builtin) {
+      case "yield": {
+        let to = hash.pairs.find((p) => p.key === "to");
+        let name = to ? this.staticString(to.value, "yield to=") : "default";
+        body.lines.push(
+          `${this.rt("yieldTo")}($_b, ${anchor}, $_ctx, ${q(name === "inverse" ? "else" : name)}, [${params.map((p) => `() => ${this.expr(p, body)}`).join(", ")}]);`
+        );
+        return;
+      }
+      case "debugger":
+        body.lines.push("debugger;");
+        return;
+      case "component": {
+        let [definition, ...rest] = params;
+        if (!definition) throw new CodegenError("`{{component}}` requires a component", node);
+        if (rest.length)
+          throw new CodegenError("positional arguments to components are not supported yet", node);
+        body.lines.push(
+          `${this.rt("invokeDyn")}($_b, ${anchor}, () => ${this.expr(definition, body)}, ${this.named(hash, body) ?? "{}"}, null, null);`
+        );
+        return;
+      }
+    }
+    if (builtin === null && (params.length > 0 || hash.pairs.length > 0)) {
+      let isStatic = path.head.type === "VarHead" && path.tail.length === 0 && body.scope.lookup(path.head.name) === void 0;
+      let definition = this.expr(path, body);
+      body.lines.push(
+        `${this.rt("appendCall")}($_b, ${anchor}, ${isStatic ? definition : `() => ${definition}`}, ${isStatic}, ${this.positional(
+          params,
+          body
+        )}, ${this.named(hash, body)}, ${flags});`
+      );
+      return;
+    }
+    if (params.length === 0 && hash.pairs.length === 0 && builtin === null) {
+      if (path.head.type === "VarHead" && path.tail.length === 0 && body.scope.lookup(path.head.name) === void 0) {
+        flags |= 1;
+      }
+    }
+    body.lines.push(
+      `${this.rt("content")}($_b, ${anchor}, () => ${this.mustacheValue(node, body)}, ${flags});`
+    );
+  }
+  /**
+   * The value of `{{path params hash}}`.
+   */
+  mustacheValue(node, body) {
+    if (node.params.length === 0 && node.hash.pairs.length === 0) {
+      if (node.path.type === "PathExpression" && this.builtin(node.path, body.scope) === null) {
+        return this.expr(node.path, body);
+      }
+      if (node.path.type !== "PathExpression" && node.path.type !== "SubExpression") {
+        return this.expr(node.path, body);
+      }
+    }
+    return this.call(node.path, node.params, node.hash, node, body);
+  }
+  block(node, anchor, body) {
+    let { path, params, hash, program, inverse } = node;
+    let builtin = path.type === "PathExpression" ? this.builtin(path, body.scope) : null;
+    let { scope } = body;
+    switch (builtin) {
+      case "if":
+      case "unless": {
+        let [condition] = params;
+        if (!condition) throw new CodegenError(`\`${builtin}\` requires a condition`, node);
+        let test = `${this.rt("bool")}(${this.expr(condition, body)})`;
+        body.lines.push(
+          `${this.rt("when")}($_b, ${anchor}, () => ${builtin === "unless" ? `!${test}` : test}, ${this.blockFn(
+            program,
+            scope
+          )}, ${this.blockFn(inverse, scope)});`
+        );
+        return;
+      }
+      case "each": {
+        let [list] = params;
+        if (!list) throw new CodegenError("`each` requires a list", node);
+        let keyPair = hash.pairs.find((p) => p.key === "key");
+        body.lines.push(
+          `${this.rt("each")}($_b, ${anchor}, () => ${this.expr(list, body)}, ${keyPair ? this.expr(keyPair.value, body) : "null"}, ${this.blockFn(program, scope)}, ${this.blockFn(inverse, scope)});`
+        );
+        return;
+      }
+      case "each-in": {
+        let [object] = params;
+        if (!object) throw new CodegenError("`each-in` requires an object", node);
+        let item = this.blockFnWith(program.body, ["entry"], scope, (id, _i, inner) => {
+          let [k, v] = program.blockParams;
+          if (k) inner.bind(k, `${id}()[0]`);
+          if (v) inner.bind(v, `${id}()[1]`);
+        });
+        body.lines.push(
+          `${this.rt("each")}($_b, ${anchor}, () => ${this.rt("entries")}(${this.expr(
+            object,
+            body
+          )}), "0", ${item}, ${this.blockFn(inverse, scope)});`
+        );
+        return;
+      }
+      case "let": {
+        let inner = scope.child();
+        program.blockParams.forEach((name, i) => {
+          let value = params[i];
+          let id = this.uid("l");
+          body.lines.push(
+            `const ${id} = ${this.rt("memo")}(() => ${value ? this.expr(value, body) : "undefined"});`
+          );
+          inner.bind(name, `${id}()`);
+        });
+        body.lines.push(
+          `${this.rt("scope")}($_b, ${anchor}, ($_b) => {
+${this.body(program.body, inner)}
+});`
+        );
+        return;
+      }
+      case "in-element": {
+        let [destination] = params;
+        if (!destination) throw new CodegenError("`in-element` requires a destination", node);
+        let append = hash.pairs.some((p) => p.key === "insertBefore");
+        body.lines.push(
+          `${this.rt("inElement")}($_b, () => ${this.expr(destination, body)}, ${append}, ${this.blockFn(
+            program,
+            scope
+          )});`
+        );
+        return;
+      }
+      case "component": {
+        let [definition] = params;
+        if (!definition) throw new CodegenError("`{{#component}}` requires a component", node);
+        body.lines.push(
+          `${this.rt("invokeDyn")}($_b, ${anchor}, () => ${this.expr(definition, body)}, ${this.named(hash, body) ?? "{}"}, ${this.blocksObject(program, inverse, scope)}, null);`
+        );
+        return;
+      }
+      case null:
+        break;
+      default:
+        throw new CodegenError(
+          `\`{{#${builtin}}}\` is not supported by the codegen compiler yet`,
+          node
+        );
+    }
+    if (params.length > 0) {
+      throw new CodegenError("positional arguments to components are not supported yet", node);
+    }
+    this.invocation(
+      path,
+      anchor,
+      this.named(hash, body) ?? "{}",
+      this.blocksObject(program, inverse, scope),
+      "null",
+      body
+    );
+  }
+  blocksObject(program, inverse, scope) {
+    let entries = [`default: ${this.blockFn(program, scope)}`];
+    if (inverse) entries.push(`else: ${this.blockFn(inverse, scope)}`);
+    return `{ ${entries.join(", ")} }`;
+  }
+  componentElement(node, anchor, body) {
+    let named = [];
+    let attrs = [];
+    for (let attr of node.attributes) {
+      if (attr.name.startsWith("@")) {
+        named.push(`${key(attr.name.slice(1))}: () => ${this.attrValue(attr.value, body)}`);
+      } else {
+        attrs.push(attr);
+      }
+    }
+    let attrsFn = "null";
+    if (attrs.length > 0 || node.modifiers.length > 0) {
+      let inner = { lines: [], scope: body.scope };
+      for (let attr of attrs) {
+        if (attr.name === "...attributes") {
+          inner.lines.push(`${this.rt("splat")}($_b, $_el, $_ctx);`);
+        } else {
+          let value = attr.value.type === "TextNode" ? q(attr.value.chars) : `() => ${this.attrValue(attr.value, inner)}`;
+          inner.lines.push(`${this.rt("attr")}($_b, $_el, ${q(attr.name)}, ${value});`);
+        }
+      }
+      for (let modifier of node.modifiers) {
+        this.modifier(modifier, "$_el", inner);
+      }
+      attrsFn = `($_b, $_el) => {
+${inner.lines.join("\n")}
+}`;
+    }
+    let blocks = "null";
+    let namedBlocks = node.children.filter(
+      (c) => c.type === "ElementNode" && c.tag.startsWith(":")
+    );
+    if (namedBlocks.length > 0) {
+      blocks = `{ ${namedBlocks.map(
+        (b) => `${key(b.tag.slice(1))}: ${this.blockFnWith(
+          b.children,
+          b.params.map((p) => p.name),
+          body.scope
+        )}`
+      ).join(", ")} }`;
+    } else if (node.children.length > 0) {
+      blocks = `{ default: ${this.blockFnWith(
+        node.children,
+        node.params.map((p) => p.name),
+        body.scope
+      )} }`;
+    }
+    this.invocation(node.path, anchor, `{ ${named.join(", ")} }`, blocks, attrsFn, body);
+  }
+  invocation(path, anchor, named, blocks, attrs, body) {
+    let { head, tail } = path;
+    let isStatic = head.type === "VarHead" && tail.length === 0 && body.scope.lookup(head.name) === void 0 && this.options.isLexical(head.name);
+    if (isStatic) {
+      body.lines.push(
+        `${this.rt("invoke")}($_b, ${anchor}, ${this.expr(path, body)}, ${named}, ${blocks}, ${attrs});`
+      );
+    } else {
+      body.lines.push(
+        `${this.rt("invokeDyn")}($_b, ${anchor}, () => ${this.expr(path, body)}, ${named}, ${blocks}, ${attrs});`
+      );
+    }
+  }
+  /////////////////////////////////////////////////////////////////////////
+  // Expressions
+  /////////////////////////////////////////////////////////////////////////
+  /**
+   * Which built-in (keyword, or well-known import) does `path` refer to?
+   */
+  builtin(path, scope) {
+    if (path.type !== "PathExpression") return null;
+    let { head, tail } = path;
+    if (head.type !== "VarHead" || tail.length > 0) return null;
+    let { name } = head;
+    if (scope.lookup(name) !== void 0) return null;
+    if (KEYWORDS.has(name)) return name;
+    if (this.options.isLexical(name)) {
+      let info = this.options.importOf?.(name);
+      if (info && SPECIALIZED[info.module]?.has(info.name)) return info.name;
+      return null;
+    }
+    return name in AUTO_IMPORTED ? name : null;
+  }
+  expr(node, body) {
+    switch (node.type) {
+      case "StringLiteral":
+        return q(node.value);
+      case "NumberLiteral":
+        return String(node.value);
+      case "BooleanLiteral":
+        return String(node.value);
+      case "NullLiteral":
+        return "null";
+      case "UndefinedLiteral":
+        return "undefined";
+      case "SubExpression":
+        return this.call(node.path, node.params, node.hash, node, body);
+      case "PathExpression":
+        return this.path(node, body);
+    }
+  }
+  path(node, body) {
+    let { head, tail } = node;
+    let base;
+    switch (head.type) {
+      case "ThisHead":
+        base = "$_s";
+        break;
+      case "AtHead":
+        base = `$_a${prop(head.name.replace(/^@/u, ""))}`;
+        break;
+      case "VarHead": {
+        let local = body.scope.lookup(head.name);
+        if (local !== void 0) {
+          base = local;
+        } else if (this.options.isLexical(head.name)) {
+          base = head.name;
+        } else if (head.name in AUTO_IMPORTED) {
+          base = this.options.importBinding(AUTO_IMPORTED[head.name], head.name);
+        } else {
+          throw new CodegenError(
+            `Attempted to use \`${head.name}\`, but it is not in scope. In strict mode, values must be imported or defined in JavaScript`,
+            node
+          );
+        }
+        break;
+      }
+    }
+    return tail.length > 0 ? `${this.rt("get")}(${[base, ...tail.map(q)].join(", ")})` : base;
+  }
+  positional(params, body) {
+    if (params.length === 0) return "null";
+    return `[${params.map((p) => `() => ${this.expr(p, body)}`).join(", ")}]`;
+  }
+  named(hash, body) {
+    if (hash.pairs.length === 0) return null;
+    return `{ ${hash.pairs.map((p) => `${key(p.key)}: () => ${this.expr(p.value, body)}`).join(", ")} }`;
+  }
+  staticString(node, what) {
+    if (node.type !== "StringLiteral")
+      throw new CodegenError(`${what} must be a string literal`, node);
+    return node.value;
+  }
+  /**
+   * `(path params hash)` (or `{{path params hash}}`).
+   */
+  call(path, params, hash, node, body) {
+    let builtin = this.builtin(path, body.scope);
+    let arg = (i) => {
+      let param = params[i];
+      return param ? this.expr(param, body) : "undefined";
+    };
+    let all = () => params.map((p) => this.expr(p, body));
+    switch (builtin) {
+      case null:
+        break;
+      case "if":
+        return `(${this.rt("bool")}(${arg(0)}) ? ${arg(1)} : ${arg(2)})`;
+      case "unless":
+        return `(${this.rt("bool")}(${arg(0)}) ? ${arg(2)} : ${arg(1)})`;
+      case "concat":
+        return `(${['""', ...all().map((p) => `${this.rt("str")}(${p})`)].join(" + ")})`;
+      case "fn":
+        return `((...$_r) => (${arg(0)})(${[...all().slice(1), "...$_r"].join(", ")}))`;
+      case "hash":
+        return `({ ${hash.pairs.map((p) => `get ${key(p.key)}() { return ${this.expr(p.value, body)}; }`).join(", ")} })`;
+      case "array":
+        return `[${all().join(", ")}]`;
+      case "get":
+        return `${this.rt("getPath")}(${arg(0)}, ${arg(1)})`;
+      case "eq":
+      case "neq":
+      case "gt":
+      case "gte":
+      case "lt":
+      case "lte":
+        return `(${arg(0)} ${COMPARISONS[builtin]} ${arg(1)})`;
+      case "not":
+        return `!${this.rt("bool")}(${arg(0)})`;
+      case "and":
+      case "or":
+        return `${this.rt(builtin)}(${all().map((p) => `() => ${p}`).join(", ")})`;
+      case "has-block":
+      case "has-block-params":
+        return `${this.rt(builtin === "has-block" ? "hasBlock" : "hasBlockParams")}($_ctx${params.length ? `, ${arg(0)}` : ""})`;
+      case "component":
+        return `${this.rt("curry")}(${arg(0)}, ${this.named(hash, body) ?? "null"})`;
+      case "log":
+        return `${this.rt("log")}(${all().join(", ")})`;
+      case "element":
+        break;
+      default:
+        throw new CodegenError(`\`${builtin}\` is not supported by the codegen compiler yet`, node);
+    }
+    let positional = this.positional(params, body);
+    let named = this.named(hash, body);
+    let id = this.uid("h");
+    let isStatic = path.type === "PathExpression" && path.head.type === "VarHead" && path.tail.length === 0 && body.scope.lookup(path.head.name) === void 0;
+    if (isStatic) {
+      body.lines.push(
+        `const ${id} = ${this.rt("helper")}($_b, ${this.expr(path, body)}, ${positional}, ${named});`
+      );
+    } else {
+      body.lines.push(
+        `const ${id} = ${this.rt("helperDyn")}($_b, () => ${this.expr(path, body)}, ${positional}, ${named});`
+      );
+    }
+    return `${id}()`;
+  }
+};
+function staticText(node) {
+  if (node.trusting || node.params.length > 0 || node.hash.pairs.length > 0) return null;
+  let { path } = node;
+  switch (path.type) {
+    case "StringLiteral":
+      return path.value;
+    case "NumberLiteral":
+    case "BooleanLiteral":
+      return String(path.value);
+    case "NullLiteral":
+    case "UndefinedLiteral":
+      return "";
+    default:
+      return null;
+  }
+}
+function generate(ast, options) {
+  let generator = new Generator(options);
+  let expression = generator.template(ast);
+  return { hoisted: generator.hoisted, expression };
+}
+
+// packages/@glimmer/compiler/lib/codegen/babel-plugin.ts
+var TEMPLATE_MODULES = /* @__PURE__ */ new Set(["@ember/template-compiler", "@ember/template-compiler/runtime"]);
+function importedName(specifier) {
+  return specifier.imported.type === "StringLiteral" ? specifier.imported.value : specifier.imported.name;
+}
+function codegenBabelPlugin(babel, options) {
+  let t = babel.types;
+  let runtimeModule = options.runtimeModule ?? "@glimmer/dom";
+  return {
+    name: "glimmer-codegen",
+    visitor: {
+      Program: {
+        enter(_path, state) {
+          state.codegen = { imports: /* @__PURE__ */ new Map(), hoisted: [], templates: 0 };
+        },
+        exit(path, state) {
+          let { imports, hoisted } = state.codegen;
+          if (imports.size === 0) return;
+          let declarations = [...imports].map(
+            ([module, names]) => t.importDeclaration(
+              [...names].map(
+                ([name, local]) => t.importSpecifier(t.identifier(local), t.identifier(name))
+              ),
+              t.stringLiteral(module)
+            )
+          );
+          let statements = hoisted.flatMap(
+            (code) => babel.template.statements.ast(code, { placeholderPattern: false })
+          );
+          path.unshiftContainer("body", [...declarations, ...statements]);
+          path.scope.crawl();
+          for (let statement of path.get("body")) {
+            if (!statement.isImportDeclaration()) continue;
+            if (!TEMPLATE_MODULES.has(statement.node.source.value)) continue;
+            for (let specifier of statement.get("specifiers")) {
+              let binding = path.scope.getBinding(specifier.node.local.name);
+              if (binding && !binding.referenced) specifier.remove();
+            }
+            if (statement.node.specifiers.length === 0) statement.remove();
+          }
+        }
+      },
+      CallExpression(path, state) {
+        let callee = path.get("callee");
+        if (!callee.isIdentifier()) return;
+        let binding = path.scope.getBinding(callee.node.name);
+        if (!binding || binding.kind !== "module" || !binding.path.isImportSpecifier()) return;
+        if (!TEMPLATE_MODULES.has(binding.path.parent.source.value)) return;
+        if (importedName(binding.path.node) !== "template") return;
+        let [source, templateOptions] = path.node.arguments;
+        let text;
+        if (t.isTemplateLiteral(source) && source.expressions.length === 0) {
+          text = source.quasis[0].value.cooked;
+        } else if (t.isStringLiteral(source)) {
+          text = source.value;
+        } else {
+          throw path.buildCodeFrameError("template() must be called with a static string");
+        }
+        let component = null;
+        if (templateOptions && t.isObjectExpression(templateOptions)) {
+          for (let property of templateOptions.properties) {
+            if (t.isObjectProperty(property) && t.isIdentifier(property.key, { name: "component" })) {
+              component = property.value;
+            }
+          }
+        }
+        let program = path.scope.getProgramParent();
+        let { imports } = state.codegen;
+        let local = (module, name) => {
+          let names = imports.get(module);
+          if (!names) imports.set(module, names = /* @__PURE__ */ new Map());
+          let existing = names.get(name);
+          if (existing) return existing;
+          let id = program.generateUid(name.replace(/\W/gu, "_"));
+          names.set(name, id);
+          return id;
+        };
+        let importOf = (name) => {
+          let found = path.scope.getBinding(name);
+          if (!found || found.kind !== "module") return void 0;
+          let module = found.path.parent.source.value;
+          if (found.path.isImportSpecifier())
+            return { module, name: importedName(found.path.node) };
+          if (found.path.isImportDefaultSpecifier()) return { module, name: "default" };
+          return void 0;
+        };
+        let ast = options.preprocess(text, { strictMode: true });
+        let { hoisted, expression } = generate(ast, {
+          isLexical: (name) => Boolean(path.scope.getBinding(name)),
+          importOf,
+          runtime: (name) => local(runtimeModule, name),
+          importBinding: local,
+          prefix: `${state.codegen.templates++}_`
+        });
+        state.codegen.hoisted.push(...hoisted);
+        let replacement = babel.template.expression.ast(expression, { placeholderPattern: false });
+        if (component) {
+          replacement = t.callExpression(t.identifier(local(runtimeModule, "setTemplate")), [
+            component,
+            replacement
+          ]);
+        }
+        path.replaceWith(replacement);
+      }
+    }
+  };
+}
+export {
+  CodegenError,
+  codegenBabelPlugin,
+  generate
+};

From 0fc08f9956b6e4bca9cc7c24eaf121077d1623be Mon Sep 17 00:00:00 2001
From: Claude <noreply@anthropic.com>
Date: Fri, 2 Oct 2026 22:28:09 +0000
Subject: [PATCH 2/2] Update the codegen flavor to the latest ember.js
 experiment

Vendors @glimmer/dom and the compiler from emberjs/ember.js#21649:

- compile with `vmInterop`, so compiled templates can render components
  that only have a VM template (e.g. from addons), and the other way around
- `@glimmer/dom/vm` is a known module (the VM interop runtime)
- allowed globals (RFC 1070) resolve in compiled templates
- the demo renders ember-primitives' <ExternalLink> from a compiled template

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01H2cNyDMVxZb1xQB6oCzX89
---
 apps/repl/public/samples/gjs-codegen-demo.gjs |  12 +
 .../ember-repl/src/services/known-modules.ts  |   4 +-
 packages/ember-repl/src/vendor/glimmer-dom.js | 860 ------------------
 .../src/vendor/glimmer-dom/index.js           | 552 +++++++++++
 .../src/vendor/glimmer-dom/shared.js          | 496 ++++++++++
 .../ember-repl/src/vendor/glimmer-dom/vm.js   | 314 +++++++
 packages/repl-sdk/src/compilers/ember/gjs.js  |  15 +-
 .../ember/vendor/codegen-compiler.js          | 283 ++++--
 8 files changed, 1570 insertions(+), 966 deletions(-)
 delete mode 100644 packages/ember-repl/src/vendor/glimmer-dom.js
 create mode 100644 packages/ember-repl/src/vendor/glimmer-dom/index.js
 create mode 100644 packages/ember-repl/src/vendor/glimmer-dom/shared.js
 create mode 100644 packages/ember-repl/src/vendor/glimmer-dom/vm.js

diff --git a/apps/repl/public/samples/gjs-codegen-demo.gjs b/apps/repl/public/samples/gjs-codegen-demo.gjs
index 45763ac0a..5eaedbe26 100644
--- a/apps/repl/public/samples/gjs-codegen-demo.gjs
+++ b/apps/repl/public/samples/gjs-codegen-demo.gjs
@@ -5,6 +5,9 @@ import { tracked } from '@glimmer/tracking';
 import { trackedArray } from '@ember/reactive/collections';
 import { on } from '@ember/modifier';
 import { fn } from '@ember/helper';
+// A component compiled for the VM (from an addon): rendered by the VM,
+// with the attributes and block from this compiled template.
+import { ExternalLink } from 'ember-primitives';
 
 const shout = (text) => `${text.toUpperCase()}!`;
 
@@ -75,6 +78,15 @@ class Todos extends Component {
 
   <Card><:title>Empty</:title></Card>
 
+  <Card>
+    <:title>From an addon</:title>
+    <:body>
+      <ExternalLink href="https://github.com/emberjs/ember.js/pull/21649" class="pr-link">
+        The ember.js PR
+      </ExternalLink>
+    </:body>
+  </Card>
+
   <style>
     .card { border: 1px solid #ccc; border-radius: 0.5rem; padding: 0.5rem 1rem; margin: 1rem 0; }
   </style>
diff --git a/packages/ember-repl/src/services/known-modules.ts b/packages/ember-repl/src/services/known-modules.ts
index a44a8e721..e27ae4cdf 100644
--- a/packages/ember-repl/src/services/known-modules.ts
+++ b/packages/ember-repl/src/services/known-modules.ts
@@ -46,7 +46,9 @@ const frameworkModules = {
    * Vendored from a branch of ember.js, see the file's header.
    */
   // @ts-ignore
-  '@glimmer/dom': () => import('../vendor/glimmer-dom.js'),
+  '@glimmer/dom': () => import('../vendor/glimmer-dom/index.js'),
+  // @ts-ignore
+  '@glimmer/dom/vm': () => import('../vendor/glimmer-dom/vm.js'),
 };
 
 const coreLibraries = {
diff --git a/packages/ember-repl/src/vendor/glimmer-dom.js b/packages/ember-repl/src/vendor/glimmer-dom.js
deleted file mode 100644
index 5db434514..000000000
--- a/packages/ember-repl/src/vendor/glimmer-dom.js
+++ /dev/null
@@ -1,860 +0,0 @@
-// @ts-nocheck
-/* eslint-disable */
-/**
- * VENDORED -- do not edit.
- *
- * The runtime for compiled templates (`@glimmer/dom`).
- * Built from https://github.com/NullVoxPopuli-ai-agent/ember.js/tree/claude/gallant-heisenberg-aovzyr (2b03eb8).
- *
- * This is an experiment: strict-mode templates compiled directly to DOM
- * operations, with no wire format and no VM.
- */
-
-// packages/@glimmer/dom/lib/core.ts
-import { associateDestroyableChild, destroy } from "@glimmer/destroyable";
-var Root = class {
-  constructor(owner, document) {
-    this.owner = owner;
-    this.document = document;
-  }
-  owner;
-  document;
-  #queue = [];
-  /**
-   * Schedule work that must happen after DOM is inserted
-   * (modifier install/update, component didCreate hooks).
-   */
-  schedule(fn) {
-    this.#queue.push(fn);
-  }
-  flush() {
-    while (this.#queue.length > 0) {
-      let queue = this.#queue;
-      this.#queue = [];
-      for (let fn of queue) fn();
-    }
-  }
-};
-var Block = class {
-  constructor(root, parent) {
-    this.root = root;
-    if (parent) associateDestroyableChild(parent, this);
-  }
-  root;
-  updaters = [];
-  update() {
-    let { updaters } = this;
-    for (let i = 0; i < updaters.length; i++) {
-      updaters[i]();
-    }
-  }
-};
-function marker(root) {
-  return root.document.createTextNode("");
-}
-function mount(parent, before, render2) {
-  let b = new Block(parent.root, parent);
-  let start = marker(parent.root);
-  let end = marker(parent.root);
-  let target = before.parentNode;
-  target.insertBefore(start, before);
-  target.insertBefore(render2(b), before);
-  target.insertBefore(end, before);
-  return { b, start, end };
-}
-function unmount(m) {
-  removeRange(m.start, m.end);
-  destroy(m.b);
-}
-function removeRange(first, last) {
-  let parent = first.parentNode;
-  if (!parent) return;
-  let node = first;
-  while (node) {
-    let next = node === last ? null : node.nextSibling;
-    parent.removeChild(node);
-    node = next;
-  }
-}
-function moveRange(m, before) {
-  let parent = before.parentNode;
-  let node = m.start;
-  while (node) {
-    let next = node === m.end ? null : node.nextSibling;
-    parent.insertBefore(node, before);
-    node = next;
-  }
-}
-function html(markup) {
-  return { markup, parsed: null };
-}
-function clone(b, t) {
-  let parsed = t.parsed;
-  if (parsed === null) {
-    parsed = t.parsed = b.root.document.createElement("template");
-    parsed.innerHTML = t.markup;
-  }
-  return b.root.document.importNode(parsed.content, true);
-}
-function at(node, ...path) {
-  for (let i of path) {
-    node = node.childNodes[i];
-  }
-  return node;
-}
-var Template = class {
-  constructor(render2) {
-    this.render = render2;
-  }
-  render;
-  toString() {
-    return "(compiled template)";
-  }
-};
-function template(render2) {
-  return new Template(render2);
-}
-var TEMPLATES = /* @__PURE__ */ new WeakMap();
-function setTemplate(definition, t) {
-  TEMPLATES.set(definition, t);
-  return definition;
-}
-function templateFor(definition) {
-  if (definition instanceof Template) return definition;
-  let pointer = definition;
-  while (pointer !== null && pointer !== Function.prototype && pointer !== Object.prototype) {
-    let found = TEMPLATES.get(pointer);
-    if (found) return found;
-    pointer = Object.getPrototypeOf(pointer);
-  }
-  return void 0;
-}
-
-// packages/@glimmer/dom/lib/attributes.ts
-import { registerDestructor } from "@glimmer/destroyable";
-
-// shim:@glimmer/validator/lib/tracking
-import { consumeTag, createCache, getValue, isConst, track } from "@glimmer/validator";
-
-// packages/@glimmer/dom/lib/attributes.ts
-var XHTML = "http://www.w3.org/1999/xhtml";
-var PROPERTIES = /* @__PURE__ */ new Set(["value", "checked", "selected", "indeterminate", "muted"]);
-var SANITIZED_TAGS = /* @__PURE__ */ new Set(["A", "BODY", "LINK", "IMG", "IFRAME", "BASE", "FORM"]);
-var SANITIZED_ATTRS = /* @__PURE__ */ new Set(["href", "src", "background", "action"]);
-var BAD_PROTOCOLS = /* @__PURE__ */ new Set(["javascript:", "vbscript:"]);
-function normalizeAttrValue(value) {
-  if (value === false || value === void 0 || value === null) return null;
-  if (value === true) return "";
-  if (typeof value === "function") return null;
-  if (typeof value.toString !== "function") return null;
-  return String(value);
-}
-function sanitize(element, name, value) {
-  if (value === null || !SANITIZED_TAGS.has(element.tagName) || !SANITIZED_ATTRS.has(name)) {
-    return value;
-  }
-  let protocol;
-  try {
-    protocol = new URL(value, "http://localhost").protocol;
-  } catch {
-    return value;
-  }
-  return BAD_PROTOCOLS.has(protocol) ? `unsafe:${value}` : value;
-}
-function setterFor(element, name) {
-  if (element.namespaceURI === XHTML && PROPERTIES.has(name) && name in element) {
-    return (value) => {
-      element[name] = value === null || value === void 0 ? name === "value" ? "" : false : value;
-    };
-  }
-  return (value) => {
-    let normalized = sanitize(element, name, normalizeAttrValue(value));
-    if (normalized === null) {
-      element.removeAttribute(name);
-    } else {
-      element.setAttribute(name, normalized);
-    }
-  };
-}
-function bind(b, value, setter) {
-  if (typeof value !== "function") {
-    setter(value);
-    return;
-  }
-  let cache = createCache(value);
-  let current = getValue(cache);
-  setter(current);
-  if (isConst(cache)) return;
-  b.updaters.push(() => {
-    let next = getValue(cache);
-    if (next !== current) {
-      current = next;
-      setter(next);
-    }
-  });
-}
-var CLASSES = /* @__PURE__ */ new WeakMap();
-function classPart(b, element, value) {
-  let state = CLASSES.get(element);
-  if (!state) {
-    state = { parts: [] };
-    let existing = element.getAttribute("class");
-    if (existing) state.parts.push(existing);
-    CLASSES.set(element, state);
-  }
-  let { parts } = state;
-  let index = parts.length;
-  parts.push("");
-  bind(b, value, (next) => {
-    parts[index] = normalizeAttrValue(next) ?? "";
-    let className = parts.filter(Boolean).join(" ");
-    if (className) {
-      element.setAttribute("class", className);
-    } else {
-      element.removeAttribute("class");
-    }
-  });
-}
-function attr(b, element, name, value) {
-  if (name === "class") {
-    classPart(b, element, value);
-  } else {
-    bind(b, value, setterFor(element, name));
-  }
-}
-function splat(b, element, ctx) {
-  ctx.attrs?.(b, element);
-}
-function listen(b, element, eventName, handler, options) {
-  let cache = createCache(handler);
-  let listener = (event) => {
-    let fn = getValue(cache);
-    if (typeof fn === "function") {
-      return fn(event);
-    }
-    throw new Error(
-      `You must pass a function as the second argument to the \`on\` modifier; you passed ${String(fn)}.`
-    );
-  };
-  element.addEventListener(eventName, listener, options);
-  registerDestructor(b, () => {
-    element.removeEventListener(eventName, listener, options);
-  });
-}
-
-// shim:@glimmer/manager/lib/internal/api
-import { getInternalComponentManager, getInternalHelperManager, getInternalModifierManager } from "@glimmer/manager";
-
-// packages/@glimmer/dom/lib/invoke.ts
-import { associateDestroyableChild as associateDestroyableChild3, registerDestructor as registerDestructor2 } from "@glimmer/destroyable";
-
-// shim:@glimmer/reference/lib/reference
-import { createComputeRef, valueForRef } from "@glimmer/reference";
-
-// packages/@glimmer/dom/lib/managers.ts
-import { associateDestroyableChild as associateDestroyableChild2, destroy as destroy2 } from "@glimmer/destroyable";
-
-// shim:@glimmer/validator/lib/validators
-import { createTag, dirtyTag, updateTag, validateTag, valueForTag } from "@glimmer/validator";
-
-// packages/@glimmer/dom/lib/managers.ts
-function capture(named, positional) {
-  let capturedNamed = /* @__PURE__ */ Object.create(null);
-  if (named) {
-    for (let key of Object.keys(named)) {
-      capturedNamed[key] = createComputeRef(named[key]);
-    }
-  }
-  let capturedPositional = (positional ?? []).map((thunk) => createComputeRef(thunk));
-  return {
-    named: capturedNamed,
-    positional: capturedPositional
-  };
-}
-function resolveHelper(definition) {
-  let manager = getInternalHelperManager(definition);
-  return typeof manager === "function" ? manager : manager.getHelper(definition);
-}
-function instantiateHelper(b, definition, args) {
-  let ref = resolveHelper(definition)(args, b.root.owner);
-  associateDestroyableChild2(b, ref);
-  return ref;
-}
-function helper(b, definition, positional, named) {
-  let ref = instantiateHelper(b, definition, capture(named, positional));
-  return () => valueForRef(ref);
-}
-function helperDyn(b, definition, positional, named) {
-  let args = capture(named, positional);
-  let definitionCache = createCache(definition);
-  let current;
-  let ref = null;
-  return () => {
-    let next = getValue(definitionCache);
-    if (next !== current || ref === null) {
-      if (ref !== null) destroy2(ref);
-      current = next;
-      ref = instantiateHelper(b, next, args);
-    }
-    return valueForRef(ref);
-  };
-}
-function modifier(b, element, definition, positional, named) {
-  let manager = getInternalModifierManager(definition);
-  let state = manager.create(
-    b.root.owner,
-    element,
-    definition,
-    capture(named, positional)
-  );
-  let destroyable = manager.getDestroyable(state);
-  if (destroyable) associateDestroyableChild2(b, destroyable);
-  let tag = manager.getTag(state);
-  if (tag === null) {
-    b.root.schedule(() => {
-      manager.install(state);
-    });
-    return;
-  }
-  let lastRevision = null;
-  let run = (hook) => {
-    updateTag(
-      tag,
-      track(() => {
-        hook(state);
-      })
-    );
-    consumeTag(tag);
-    lastRevision = valueForTag(tag);
-  };
-  b.root.schedule(() => {
-    run((s) => {
-      manager.install(s);
-    });
-  });
-  b.updaters.push(() => {
-    consumeTag(tag);
-    if (lastRevision === null || validateTag(tag, lastRevision)) return;
-    lastRevision = null;
-    b.root.schedule(() => {
-      run((s) => {
-        manager.update(s);
-      });
-    });
-  });
-}
-
-// packages/@glimmer/dom/lib/invoke.ts
-var Curried = class {
-  constructor(definition, named) {
-    this.definition = definition;
-    this.named = named;
-  }
-  definition;
-  named;
-};
-function curry(definition, named) {
-  if (!definition) return null;
-  return new Curried(definition, named ?? {});
-}
-function isComponentDefinition(value) {
-  if (value instanceof Template || value instanceof Curried) return true;
-  if (typeof value !== "object" && typeof value !== "function" || value === null) return false;
-  if (templateFor(value)) return true;
-  return getInternalComponentManager(value, true) !== null;
-}
-var vmFallback = null;
-function setVMFallback(fallback) {
-  vmFallback = fallback;
-}
-function describe(definition) {
-  return typeof definition === "function" ? definition.name || "(anonymous component)" : Object.prototype.toString.call(definition);
-}
-function argsFor(captured) {
-  let args = /* @__PURE__ */ Object.create(null);
-  for (let key of Object.keys(captured.named)) {
-    let ref = captured.named[key];
-    Object.defineProperty(args, key, { enumerable: true, get: () => valueForRef(ref) });
-  }
-  return args;
-}
-function island(b, definition, named) {
-  if (!vmFallback) {
-    throw new Error(
-      `${describe(definition)} does not have a compiled template, and there is no VM fallback registered to render it.`
-    );
-  }
-  let args = /* @__PURE__ */ Object.create(null);
-  for (let key of Object.keys(named)) {
-    Object.defineProperty(args, key, { enumerable: true, get: named[key] });
-  }
-  let element = b.root.document.createElement("glimmer-island");
-  element.style.display = "contents";
-  let result = vmFallback(definition, element, b.root.owner, args);
-  registerDestructor2(b, () => {
-    result.destroy();
-  });
-  return element;
-}
-function instantiate(b, definition, named, blocks, attrs) {
-  while (definition instanceof Curried) {
-    named = { ...definition.named, ...named };
-    definition = definition.definition;
-  }
-  let compiled = templateFor(definition);
-  if (!compiled) return island(b, definition, named);
-  let captured = capture(named, null);
-  let args = argsFor(captured);
-  if (compiled === definition) {
-    return compiled.render(b, { self: void 0, args, blocks, attrs });
-  }
-  let manager = getInternalComponentManager(definition);
-  if (!("getDelegateFor" in manager)) {
-    throw new Error(
-      `Compiled templates can only be used with components that have a custom component manager (like @glimmer/component). ${describe(definition)} does not.`
-    );
-  }
-  let state = manager.create(b.root.owner, definition, { capture: () => captured });
-  let self = valueForRef(manager.getSelf(state));
-  let destroyable = manager.getDestroyable(state);
-  if (destroyable) associateDestroyableChild3(b, destroyable);
-  b.root.schedule(() => {
-    manager.didCreate(state);
-  });
-  return compiled.render(b, { self, args, blocks, attrs });
-}
-function invoke(b, anchor, definition, named, blocks, attrs) {
-  let m = mount(b, anchor, (child) => instantiate(child, definition, named, blocks, attrs));
-  b.updaters.push(() => {
-    m.b.update();
-  });
-}
-function invokeDyn(b, anchor, definition, named, blocks, attrs) {
-  let cache = createCache(definition);
-  let current = getValue(cache);
-  let render2 = (value) => value ? mount(b, anchor, (child) => instantiate(child, value, named, blocks, attrs)) : null;
-  let m = render2(current);
-  b.updaters.push(() => {
-    let next = getValue(cache);
-    if (next === current) {
-      m?.b.update();
-      return;
-    }
-    if (m) unmount(m);
-    current = next;
-    m = render2(next);
-  });
-}
-
-// packages/@glimmer/dom/lib/values.ts
-import { getPath as globalGetPath, getProp, toBool } from "@glimmer/global-context";
-function get(obj, ...keys) {
-  for (let key of keys) {
-    if (obj === null || obj === void 0) return void 0;
-    obj = getProp(obj, key);
-  }
-  return obj;
-}
-function getPath(obj, path) {
-  if (obj === null || obj === void 0 || path === null || path === void 0) return void 0;
-  return globalGetPath(obj, String(path));
-}
-function bool(value) {
-  return toBool(value);
-}
-function isEmpty(value) {
-  return value === null || value === void 0 || typeof value.toString !== "function";
-}
-function str(value) {
-  return isEmpty(value) ? "" : String(value);
-}
-function and(...values) {
-  let last;
-  for (let value of values) {
-    last = value();
-    if (!toBool(last)) return last;
-  }
-  return last;
-}
-function or(...values) {
-  let last;
-  for (let value of values) {
-    last = value();
-    if (toBool(last)) return last;
-  }
-  return last;
-}
-function memo(fn) {
-  let cache = createCache(fn);
-  return () => getValue(cache);
-}
-function log(...values) {
-  console.log(...values);
-  return void 0;
-}
-function entries(obj) {
-  if (obj === null || obj === void 0) return [];
-  if (obj instanceof Map) return Array.from(obj.entries());
-  return Object.keys(obj).map((key) => [key, get(obj, key)]);
-}
-function hasBlock(ctx, name = "default") {
-  return Boolean(ctx.blocks?.[name]);
-}
-function hasBlockParams(ctx, name = "default") {
-  let block2 = ctx.blocks?.[name];
-  return block2 ? block2.length > 1 : false;
-}
-
-// packages/@glimmer/dom/lib/content.ts
-var MAY_CALL = 1;
-var TRUSTING = 2;
-function isSafeString(value) {
-  return typeof value === "object" && value !== null && typeof value.toHTML === "function";
-}
-function isNode(value) {
-  return typeof value === "object" && value !== null && typeof value.nodeType === "number";
-}
-function kindOf(value, flags) {
-  if (typeof value === "string") return flags & TRUSTING ? 1 /* html */ : 0 /* text */;
-  if (value === null || value === void 0) return 0 /* text */;
-  if (typeof value !== "object" && typeof value !== "function") return 0 /* text */;
-  if (isSafeString(value)) return 1 /* html */;
-  if (isNode(value)) return 2 /* node */;
-  if (isComponentDefinition(value)) return 3 /* component */;
-  return 0 /* text */;
-}
-function isHelperLike(value) {
-  if (isComponentDefinition(value)) return false;
-  if (typeof value === "function") return true;
-  return typeof value === "object" && value !== null && getInternalHelperManager(value, true) !== null;
-}
-function insertNodes(parent, before, nodes) {
-  let doc = parent.ownerDocument ?? parent;
-  if (nodes.nodeType === 11) {
-    if (!nodes.firstChild) nodes.appendChild(doc.createTextNode(""));
-    let first = nodes.firstChild;
-    let last = nodes.lastChild;
-    parent.insertBefore(nodes, before);
-    return { first, last, text: null, mounted: null };
-  }
-  parent.insertBefore(nodes, before);
-  return { first: nodes, last: nodes, text: null, mounted: null };
-}
-function render(b, parent, before, kind, value, flags) {
-  let doc = b.root.document;
-  switch (kind) {
-    case 0 /* text */: {
-      let text = doc.createTextNode(str(value));
-      parent.insertBefore(text, before);
-      return { first: text, last: text, text, mounted: null };
-    }
-    case 1 /* html */: {
-      let t = doc.createElement("template");
-      t.innerHTML = flags & TRUSTING && !isSafeString(value) ? str(value) : value.toHTML();
-      return insertNodes(parent, before, t.content);
-    }
-    case 2 /* node */:
-      return insertNodes(parent, before, value);
-    case 3 /* component */: {
-      let mounted = mount(
-        b,
-        before,
-        (child) => instantiate(child, value, {}, null, null)
-      );
-      return { first: mounted.start, last: mounted.end, text: null, mounted };
-    }
-  }
-}
-function clear(slot) {
-  if (slot.mounted) {
-    unmount(slot.mounted);
-  } else {
-    removeRange(slot.first, slot.last);
-  }
-}
-function content(b, anchor, fn, flags = 0) {
-  if (flags & MAY_CALL) {
-    let definition = fn();
-    if (isHelperLike(definition)) fn = helper(b, definition, null, null);
-  }
-  let cache = createCache(fn);
-  let value = getValue(cache);
-  let kind = kindOf(value, flags);
-  let parent = anchor.parentNode;
-  let slot = render(b, parent, anchor, kind, value, flags);
-  parent.removeChild(anchor);
-  if (isConst(cache) && kind !== 3 /* component */) return;
-  b.updaters.push(() => {
-    let next = getValue(cache);
-    if (next === value) {
-      slot.mounted?.b.update();
-      return;
-    }
-    let nextKind = kindOf(next, flags);
-    if (kind === 0 /* text */ && nextKind === 0 /* text */ && slot.text) {
-      slot.text.data = str(next);
-      value = next;
-      return;
-    }
-    let nextSlot = render(b, slot.first.parentNode, slot.first, nextKind, next, flags);
-    clear(slot);
-    slot = nextSlot;
-    kind = nextKind;
-    value = next;
-  });
-}
-function appendCall(b, anchor, definition, isStatic, positional, named, flags = 0) {
-  let value = isStatic ? definition : definition();
-  if (isComponentDefinition(value)) {
-    if (positional) {
-      throw new Error("positional arguments to components are not supported yet");
-    }
-    if (isStatic) {
-      invoke(b, anchor, value, named ?? {}, null, null);
-    } else {
-      invokeDyn(b, anchor, definition, named ?? {}, null, null);
-    }
-    return;
-  }
-  let result = isStatic ? helper(b, value, positional, named) : helperDyn(b, definition, positional, named);
-  content(b, anchor, result, flags);
-}
-
-// shim:@glimmer/reference/lib/iterable
-import { createIteratorRef } from "@glimmer/reference";
-
-// shim:@glimmer/validator/lib/meta
-import { tagFor } from "@glimmer/validator";
-
-// packages/@glimmer/dom/lib/control-flow.ts
-function when(b, anchor, condition, consequent, alternate) {
-  let cache = createCache(condition);
-  let current = Boolean(getValue(cache));
-  let render2 = (value) => {
-    let fn = value ? consequent : alternate;
-    return fn ? mount(b, anchor, fn) : null;
-  };
-  let m = render2(current);
-  b.updaters.push(() => {
-    let next = Boolean(getValue(cache));
-    if (next === current) {
-      m?.b.update();
-      return;
-    }
-    if (m) unmount(m);
-    current = next;
-    m = render2(next);
-  });
-}
-function cell(initial) {
-  let tag = createTag();
-  let value = initial;
-  return {
-    read: () => {
-      consumeTag(tag);
-      return value;
-    },
-    set(next) {
-      if (next !== value) {
-        value = next;
-        dirtyTag(tag);
-      }
-    }
-  };
-}
-function each(b, anchor, list, key, item, inverse) {
-  let listRef = createComputeRef(() => {
-    let value = list();
-    if (typeof value === "object" && value !== null) consumeTag(tagFor(value, "[]"));
-    return value;
-  });
-  let iteratorRef = createIteratorRef(listRef, key ?? "@identity");
-  let rows = [];
-  let byKey = /* @__PURE__ */ new Map();
-  let inverseMounted = null;
-  let lastIterator = null;
-  let sync = () => {
-    let iterator = valueForRef(iteratorRef);
-    if (iterator === lastIterator) {
-      for (let row of rows) row.m?.b.update();
-      inverseMounted?.b.update();
-      return;
-    }
-    lastIterator = iterator;
-    let nextRows = [];
-    let nextByKey = /* @__PURE__ */ new Map();
-    for (let entry = iterator.next(); entry !== null; entry = iterator.next()) {
-      let row = byKey.get(entry.key);
-      if (row) {
-        row.value.set(entry.value);
-        row.index.set(entry.memo);
-      } else {
-        row = { value: cell(entry.value), index: cell(entry.memo), m: null };
-      }
-      nextByKey.set(entry.key, row);
-      nextRows.push(row);
-    }
-    for (let [k, row] of byKey) {
-      if (nextByKey.get(k) !== row && row.m) unmount(row.m);
-    }
-    let before = anchor;
-    for (let i = nextRows.length - 1; i >= 0; i--) {
-      let row = nextRows[i];
-      if (row.m === null) {
-        let { value, index } = row;
-        row.m = mount(b, before, (child) => item(child, value.read, index.read));
-      } else {
-        if (row.m.end.nextSibling !== before) moveRange(row.m, before);
-        row.m.b.update();
-      }
-      before = row.m.start;
-    }
-    rows = nextRows;
-    byKey = nextByKey;
-    if (rows.length === 0 && inverse && !inverseMounted) {
-      inverseMounted = mount(b, anchor, inverse);
-    } else if (rows.length > 0 && inverseMounted) {
-      unmount(inverseMounted);
-      inverseMounted = null;
-    }
-  };
-  sync();
-  b.updaters.push(sync);
-}
-function block(b, anchor, fn, params) {
-  let m = mount(b, anchor, (child) => fn(child, ...params));
-  b.updaters.push(() => {
-    m.b.update();
-  });
-}
-function yieldTo(b, anchor, ctx, name, params) {
-  let fn = ctx.blocks?.[name] ?? (name === "else" ? ctx.blocks?.["inverse"] : void 0);
-  if (fn) block(b, anchor, fn, params);
-}
-function scope(b, anchor, fn) {
-  block(b, anchor, fn, []);
-}
-function inElement(b, destination, append, fn) {
-  let cache = createCache(destination);
-  let current = null;
-  let m = null;
-  let end = null;
-  let render2 = (target) => {
-    current = target;
-    if (!target) return;
-    if (!append) target.innerHTML = "";
-    end = marker(b.root);
-    target.appendChild(end);
-    m = mount(b, end, fn);
-  };
-  render2(getValue(cache));
-  b.updaters.push(() => {
-    let next = getValue(cache);
-    if (next === current) {
-      m?.b.update();
-      return;
-    }
-    if (m) unmount(m);
-    if (end) removeRange(end, end);
-    m = null;
-    end = null;
-    render2(next);
-  });
-}
-
-// packages/@glimmer/dom/lib/render.ts
-import { destroy as destroy3 } from "@glimmer/destroyable";
-
-// shim:@ember/-internals/glimmer/lib/base-renderer
-import { renderComponent } from "@ember/renderer";
-
-// packages/@glimmer/dom/lib/render.ts
-import { _backburner } from "@ember/runloop";
-setVMFallback((definition, into, owner, args) => renderComponent(definition, { into, owner, args }));
-function renderComponent2(component, {
-  into,
-  owner = {},
-  args
-}) {
-  let root = new Root(owner, into.ownerDocument);
-  let b = new Block(root, null);
-  let named = {};
-  if (args) {
-    for (let key of Object.keys(args)) named[key] = () => args[key];
-  }
-  into.innerHTML = "";
-  let end = marker(root);
-  into.appendChild(end);
-  let tag;
-  let revision;
-  let destroyed = false;
-  let pass = (fn) => {
-    tag = track(() => {
-      fn();
-      root.flush();
-    });
-    revision = valueForTag(tag);
-  };
-  pass(() => {
-    let m = mount(b, end, (child) => instantiate(child, component, named, null, null));
-    b.updaters.push(() => {
-      m.b.update();
-    });
-  });
-  let rerender = () => {
-    if (destroyed || validateTag(tag, revision)) return;
-    pass(() => {
-      b.update();
-    });
-  };
-  _backburner.on("end", rerender);
-  return {
-    rerender,
-    destroy() {
-      if (destroyed) return;
-      destroyed = true;
-      _backburner.off("end", rerender);
-      removeRange(into.firstChild, end);
-      destroy3(b);
-    }
-  };
-}
-export {
-  MAY_CALL,
-  TRUSTING,
-  Template,
-  and,
-  appendCall,
-  at,
-  attr,
-  bool,
-  clone,
-  content,
-  curry,
-  each,
-  entries,
-  get,
-  getPath,
-  hasBlock,
-  hasBlockParams,
-  helper,
-  helperDyn,
-  html,
-  inElement,
-  invoke,
-  invokeDyn,
-  listen,
-  log,
-  memo,
-  modifier,
-  or,
-  renderComponent2 as renderComponent,
-  scope,
-  setTemplate,
-  setVMFallback,
-  splat,
-  str,
-  template,
-  when,
-  yieldTo
-};
diff --git a/packages/ember-repl/src/vendor/glimmer-dom/index.js b/packages/ember-repl/src/vendor/glimmer-dom/index.js
new file mode 100644
index 000000000..6513794b5
--- /dev/null
+++ b/packages/ember-repl/src/vendor/glimmer-dom/index.js
@@ -0,0 +1,552 @@
+// @ts-nocheck
+/* eslint-disable */
+/**
+ * VENDORED -- do not edit.
+ *
+ * The runtime for compiled templates (`@glimmer/dom`, `@glimmer/dom/vm`).
+ * Built from https://github.com/NullVoxPopuli-ai-agent/ember.js/tree/claude/gallant-heisenberg-aovzyr (af3aef79),
+ * see https://github.com/emberjs/ember.js/pull/21649
+ *
+ * This is an experiment: strict-mode templates compiled directly to DOM
+ * operations, with no wire format and no VM.
+ */
+import {
+  Template,
+  at,
+  clone,
+  consumeTag,
+  createCache,
+  createComputeRef,
+  createTag,
+  curry,
+  dirtyTag,
+  getInternalHelperManager,
+  getValue,
+  helper,
+  helperDyn,
+  html,
+  instantiate,
+  invoke,
+  invokeDyn,
+  isComponentDefinition,
+  isConst,
+  marker,
+  modifier,
+  mount,
+  moveRange,
+  removeRange,
+  renderComponent,
+  setTemplate,
+  setVMFallback,
+  template,
+  unmount,
+  valueForRef
+} from "./shared.js";
+
+// packages/@glimmer/dom/lib/attributes.ts
+import { registerDestructor } from "@glimmer/destroyable";
+var XHTML = "http://www.w3.org/1999/xhtml";
+var PROPERTIES = /* @__PURE__ */ new Set(["value", "checked", "selected", "indeterminate", "muted"]);
+var SANITIZED_TAGS = /* @__PURE__ */ new Set(["A", "BODY", "LINK", "IMG", "IFRAME", "BASE", "FORM"]);
+var SANITIZED_ATTRS = /* @__PURE__ */ new Set(["href", "src", "background", "action"]);
+var BAD_PROTOCOLS = /* @__PURE__ */ new Set(["javascript:", "vbscript:"]);
+function normalizeAttrValue(value) {
+  if (value === false || value === void 0 || value === null) return null;
+  if (value === true) return "";
+  if (typeof value === "function") return null;
+  if (typeof value.toString !== "function") return null;
+  return String(value);
+}
+function sanitize(element2, name, value) {
+  if (value === null || !SANITIZED_TAGS.has(element2.tagName) || !SANITIZED_ATTRS.has(name)) {
+    return value;
+  }
+  let protocol;
+  try {
+    protocol = new URL(value, "http://localhost").protocol;
+  } catch {
+    return value;
+  }
+  return BAD_PROTOCOLS.has(protocol) ? `unsafe:${value}` : value;
+}
+function setterFor(element2, name) {
+  if (element2.namespaceURI === XHTML && PROPERTIES.has(name) && name in element2) {
+    return (value) => {
+      element2[name] = value === null || value === void 0 ? name === "value" ? "" : false : value;
+    };
+  }
+  return (value) => {
+    let normalized = sanitize(element2, name, normalizeAttrValue(value));
+    if (normalized === null) {
+      element2.removeAttribute(name);
+    } else {
+      element2.setAttribute(name, normalized);
+    }
+  };
+}
+function bind(b, value, setter) {
+  if (typeof value !== "function") {
+    setter(value);
+    return;
+  }
+  let cache = createCache(value);
+  let current = getValue(cache);
+  setter(current);
+  if (isConst(cache)) return;
+  b.updaters.push(() => {
+    let next = getValue(cache);
+    if (next !== current) {
+      current = next;
+      setter(next);
+    }
+  });
+}
+var CLASSES = /* @__PURE__ */ new WeakMap();
+function classPart(b, element2, value) {
+  let state = CLASSES.get(element2);
+  if (!state) {
+    state = { parts: [] };
+    let existing = element2.getAttribute("class");
+    if (existing) state.parts.push(existing);
+    CLASSES.set(element2, state);
+  }
+  let { parts } = state;
+  let index = parts.length;
+  parts.push("");
+  bind(b, value, (next) => {
+    parts[index] = normalizeAttrValue(next) ?? "";
+    let className = parts.filter(Boolean).join(" ");
+    if (className) {
+      element2.setAttribute("class", className);
+    } else {
+      element2.removeAttribute("class");
+    }
+  });
+}
+function attr(b, element2, name, value) {
+  if (name === "class") {
+    classPart(b, element2, value);
+  } else {
+    bind(b, value, setterFor(element2, name));
+  }
+}
+function splat(b, element2, ctx) {
+  ctx.attrs?.(b, element2);
+}
+function describeElement(element2) {
+  return element2.tagName.toLowerCase() + (element2.id ? `#${element2.id}` : "") + Array.from(element2.classList).map((c) => `.${c}`).join("");
+}
+function assertHandler(fn, element2) {
+  if (typeof fn !== "function") {
+    throw new Error(
+      `You must pass a function as the second argument to the \`on\` modifier; you passed ${fn === null ? "null" : typeof fn}. While rendering:
+
+(unknown) on ${describeElement(element2)}`
+    );
+  }
+}
+function listen(b, element2, eventName, handler, options) {
+  let cache = createCache(handler);
+  let listener = (event) => {
+    let fn = getValue(cache);
+    assertHandler(fn, element2);
+    return fn(event);
+  };
+  b.root.schedule(() => {
+    if (typeof eventName !== "string" || !eventName) {
+      throw new Error(
+        `You must pass a valid DOM event name as the first argument to the \`on\` modifier on ${describeElement(element2)}`
+      );
+    }
+    assertHandler(getValue(cache), element2);
+    element2.addEventListener(eventName, listener, options);
+    registerDestructor(b, () => {
+      element2.removeEventListener(eventName, listener, options);
+    });
+  });
+}
+
+// packages/@glimmer/dom/lib/values.ts
+import { getPath as globalGetPath, getProp, toBool } from "@glimmer/global-context";
+function get(obj, ...keys) {
+  for (let key of keys) {
+    if (obj === null || obj === void 0) return void 0;
+    obj = getProp(obj, key);
+  }
+  return obj;
+}
+function getPath(obj, path) {
+  if (obj === null || obj === void 0 || path === null || path === void 0) return void 0;
+  return globalGetPath(obj, String(path));
+}
+function bool(value) {
+  return toBool(value);
+}
+function isEmpty(value) {
+  return value === null || value === void 0 || typeof value.toString !== "function";
+}
+function str(value) {
+  return isEmpty(value) ? "" : String(value);
+}
+function and(...values) {
+  let last;
+  for (let value of values) {
+    last = value();
+    if (!toBool(last)) return last;
+  }
+  return last;
+}
+function or(...values) {
+  let last;
+  for (let value of values) {
+    last = value();
+    if (toBool(last)) return last;
+  }
+  return last;
+}
+function memo(fn) {
+  let cache = createCache(fn);
+  return () => getValue(cache);
+}
+function log(...values) {
+  console.log(...values);
+  return void 0;
+}
+function entries(obj) {
+  if (obj === null || obj === void 0) return [];
+  if (obj instanceof Map) return Array.from(obj.entries());
+  return Object.keys(obj).map((key) => [key, get(obj, key)]);
+}
+function hasBlock(ctx, name = "default") {
+  return Boolean(ctx.blocks?.[name]);
+}
+function hasBlockParams(ctx, name = "default") {
+  let block2 = ctx.blocks?.[name];
+  return block2 ? block2.length > 1 : false;
+}
+
+// packages/@glimmer/dom/lib/content.ts
+var MAY_CALL = 1;
+var TRUSTING = 2;
+function isSafeString(value) {
+  return typeof value === "object" && value !== null && typeof value.toHTML === "function";
+}
+function isNode(value) {
+  return typeof value === "object" && value !== null && typeof value.nodeType === "number";
+}
+function kindOf(value, flags) {
+  if (typeof value === "string") return flags & TRUSTING ? 1 /* html */ : 0 /* text */;
+  if (value === null || value === void 0) return 0 /* text */;
+  if (typeof value !== "object" && typeof value !== "function") return 0 /* text */;
+  if (isSafeString(value)) return 1 /* html */;
+  if (isNode(value)) return 2 /* node */;
+  if (isComponentDefinition(value)) return 3 /* component */;
+  return 0 /* text */;
+}
+function isHelperLike(value) {
+  if (isComponentDefinition(value)) return false;
+  if (typeof value === "function") return true;
+  return typeof value === "object" && value !== null && getInternalHelperManager(value, true) !== null;
+}
+function insertNodes(parent, before, nodes) {
+  let doc = parent.ownerDocument ?? parent;
+  if (nodes.nodeType === 11) {
+    if (!nodes.firstChild) nodes.appendChild(doc.createTextNode(""));
+    let first = nodes.firstChild;
+    let last = nodes.lastChild;
+    parent.insertBefore(nodes, before);
+    return { first, last, text: null, mounted: null };
+  }
+  parent.insertBefore(nodes, before);
+  return { first: nodes, last: nodes, text: null, mounted: null };
+}
+function render(b, parent, before, kind, value, flags) {
+  let doc = b.root.document;
+  switch (kind) {
+    case 0 /* text */: {
+      let text = doc.createTextNode(str(value));
+      parent.insertBefore(text, before);
+      return { first: text, last: text, text, mounted: null };
+    }
+    case 1 /* html */: {
+      let t = doc.createElement("template");
+      t.innerHTML = flags & TRUSTING && !isSafeString(value) ? str(value) : value.toHTML();
+      return insertNodes(parent, before, t.content);
+    }
+    case 2 /* node */:
+      return insertNodes(parent, before, value);
+    case 3 /* component */: {
+      let mounted = mount(
+        b,
+        before,
+        (child) => instantiate(child, value, {}, null, null)
+      );
+      return { first: mounted.start, last: mounted.end, text: null, mounted };
+    }
+  }
+}
+function clear(slot) {
+  if (slot.mounted) {
+    unmount(slot.mounted);
+  } else {
+    removeRange(slot.first, slot.last);
+  }
+}
+function content(b, anchor, fn, flags = 0) {
+  if (flags & MAY_CALL) {
+    let definition = fn();
+    if (isHelperLike(definition)) fn = helper(b, definition, null, null);
+  }
+  let cache = createCache(fn);
+  let value = getValue(cache);
+  let kind = kindOf(value, flags);
+  let parent = anchor.parentNode;
+  let slot = render(b, parent, anchor, kind, value, flags);
+  parent.removeChild(anchor);
+  if (isConst(cache) && kind !== 3 /* component */) return;
+  b.updaters.push(() => {
+    let next = getValue(cache);
+    if (next === value) {
+      slot.mounted?.b.update();
+      return;
+    }
+    let nextKind = kindOf(next, flags);
+    if (kind === 0 /* text */ && nextKind === 0 /* text */ && slot.text) {
+      slot.text.data = str(next);
+      value = next;
+      return;
+    }
+    let nextSlot = render(b, slot.first.parentNode, slot.first, nextKind, next, flags);
+    clear(slot);
+    slot = nextSlot;
+    kind = nextKind;
+    value = next;
+  });
+}
+function appendCall(b, anchor, definition, isStatic, positional, named, flags = 0) {
+  let value = isStatic ? definition : definition();
+  if (isComponentDefinition(value)) {
+    if (positional) {
+      throw new Error("positional arguments to components are not supported yet");
+    }
+    if (isStatic) {
+      invoke(b, anchor, value, named ?? {}, null, null);
+    } else {
+      invokeDyn(b, anchor, definition, named ?? {}, null, null);
+    }
+    return;
+  }
+  let result = isStatic ? helper(b, value, positional, named) : helperDyn(b, definition, positional, named);
+  content(b, anchor, result, flags);
+}
+
+// shim:@glimmer/reference/lib/iterable
+import { createIteratorRef } from "@glimmer/reference";
+
+// shim:@glimmer/validator/lib/meta
+import { tagFor } from "@glimmer/validator";
+
+// packages/@glimmer/dom/lib/control-flow.ts
+function when(b, anchor, condition, consequent, alternate) {
+  let cache = createCache(condition);
+  let current = Boolean(getValue(cache));
+  let render2 = (value) => {
+    let fn = value ? consequent : alternate;
+    return fn ? mount(b, anchor, fn) : null;
+  };
+  let m = render2(current);
+  b.updaters.push(() => {
+    let next = Boolean(getValue(cache));
+    if (next === current) {
+      m?.b.update();
+      return;
+    }
+    if (m) unmount(m);
+    current = next;
+    m = render2(next);
+  });
+}
+function cell(initial) {
+  let tag = createTag();
+  let value = initial;
+  return {
+    read: () => {
+      consumeTag(tag);
+      return value;
+    },
+    set(next) {
+      if (next !== value) {
+        value = next;
+        dirtyTag(tag);
+      }
+    }
+  };
+}
+function each(b, anchor, list, key, item, inverse) {
+  let listRef = createComputeRef(() => {
+    let value = list();
+    if (typeof value === "object" && value !== null) consumeTag(tagFor(value, "[]"));
+    return value;
+  });
+  let iteratorRef = createIteratorRef(listRef, key ?? "@identity");
+  let rows = [];
+  let byKey = /* @__PURE__ */ new Map();
+  let inverseMounted = null;
+  let lastIterator = null;
+  let sync = () => {
+    let iterator = valueForRef(iteratorRef);
+    if (iterator === lastIterator) {
+      for (let row of rows) row.m?.b.update();
+      inverseMounted?.b.update();
+      return;
+    }
+    lastIterator = iterator;
+    let nextRows = [];
+    let nextByKey = /* @__PURE__ */ new Map();
+    for (let entry = iterator.next(); entry !== null; entry = iterator.next()) {
+      let row = byKey.get(entry.key);
+      if (row) {
+        row.value.set(entry.value);
+        row.index.set(entry.memo);
+      } else {
+        row = { value: cell(entry.value), index: cell(entry.memo), m: null };
+      }
+      nextByKey.set(entry.key, row);
+      nextRows.push(row);
+    }
+    for (let [k, row] of byKey) {
+      if (nextByKey.get(k) !== row && row.m) unmount(row.m);
+    }
+    let before = anchor;
+    for (let i = nextRows.length - 1; i >= 0; i--) {
+      let row = nextRows[i];
+      if (row.m === null) {
+        let { value, index } = row;
+        row.m = mount(b, before, (child) => item(child, value.read, index.read));
+      } else {
+        if (row.m.end.nextSibling !== before) moveRange(row.m, before);
+        row.m.b.update();
+      }
+      before = row.m.start;
+    }
+    rows = nextRows;
+    byKey = nextByKey;
+    if (rows.length === 0 && inverse && !inverseMounted) {
+      inverseMounted = mount(b, anchor, inverse);
+    } else if (rows.length > 0 && inverseMounted) {
+      unmount(inverseMounted);
+      inverseMounted = null;
+    }
+  };
+  sync();
+  b.updaters.push(sync);
+}
+function block(b, anchor, fn, params) {
+  let m = mount(b, anchor, (child) => fn(child, ...params));
+  b.updaters.push(() => {
+    m.b.update();
+  });
+}
+function yieldTo(b, anchor, ctx, name, params) {
+  let fn = ctx.blocks?.[name] ?? (name === "else" ? ctx.blocks?.["inverse"] : void 0);
+  if (fn) block(b, anchor, fn, params);
+}
+function scope(b, anchor, fn) {
+  block(b, anchor, fn, []);
+}
+function inElement(b, destination, append, fn) {
+  let cache = createCache(destination);
+  let current = null;
+  let m = null;
+  let end = null;
+  let render2 = (target) => {
+    current = target;
+    if (!target) return;
+    if (!append) target.innerHTML = "";
+    end = marker(b.root);
+    target.appendChild(end);
+    m = mount(b, end, fn);
+  };
+  render2(getValue(cache));
+  b.updaters.push(() => {
+    let next = getValue(cache);
+    if (next === current) {
+      m?.b.update();
+      return;
+    }
+    if (m) unmount(m);
+    if (end) removeRange(end, end);
+    m = null;
+    end = null;
+    render2(next);
+  });
+}
+
+// packages/@glimmer/dom/lib/element.ts
+var ELEMENTS = /* @__PURE__ */ new Map();
+function element(tagName) {
+  if (typeof tagName !== "string") {
+    throw new Error(
+      `The argument passed to the \`element\` helper must be a string (you passed \`${String(tagName)}\`)`
+    );
+  }
+  let existing = ELEMENTS.get(tagName);
+  if (existing) return existing;
+  let created = template((b, ctx) => {
+    let doc = b.root.document;
+    let fragment = doc.createDocumentFragment();
+    let anchor = marker(b.root);
+    if (tagName === "") {
+      fragment.appendChild(anchor);
+    } else {
+      let el = doc.createElement(tagName);
+      splat(b, el, ctx);
+      el.appendChild(anchor);
+      fragment.appendChild(el);
+    }
+    yieldTo(b, anchor, ctx, "default", []);
+    return fragment;
+  });
+  ELEMENTS.set(tagName, created);
+  return created;
+}
+export {
+  MAY_CALL,
+  TRUSTING,
+  Template,
+  and,
+  appendCall,
+  at,
+  attr,
+  bool,
+  clone,
+  content,
+  curry,
+  each,
+  element,
+  entries,
+  get,
+  getPath,
+  hasBlock,
+  hasBlockParams,
+  helper,
+  helperDyn,
+  html,
+  inElement,
+  invoke,
+  invokeDyn,
+  listen,
+  log,
+  memo,
+  modifier,
+  or,
+  renderComponent,
+  scope,
+  setTemplate,
+  setVMFallback,
+  splat,
+  str,
+  template,
+  when,
+  yieldTo
+};
diff --git a/packages/ember-repl/src/vendor/glimmer-dom/shared.js b/packages/ember-repl/src/vendor/glimmer-dom/shared.js
new file mode 100644
index 000000000..c1cd5b137
--- /dev/null
+++ b/packages/ember-repl/src/vendor/glimmer-dom/shared.js
@@ -0,0 +1,496 @@
+// @ts-nocheck
+/* eslint-disable */
+/**
+ * VENDORED -- do not edit.
+ *
+ * The runtime for compiled templates (`@glimmer/dom`, `@glimmer/dom/vm`).
+ * Built from https://github.com/NullVoxPopuli-ai-agent/ember.js/tree/claude/gallant-heisenberg-aovzyr (af3aef79),
+ * see https://github.com/emberjs/ember.js/pull/21649
+ *
+ * This is an experiment: strict-mode templates compiled directly to DOM
+ * operations, with no wire format and no VM.
+ */
+
+// packages/@glimmer/dom/lib/core.ts
+import { associateDestroyableChild, destroy } from "@glimmer/destroyable";
+var Root = class {
+  constructor(owner, document) {
+    this.owner = owner;
+    this.document = document;
+  }
+  owner;
+  document;
+  #queue = [];
+  /**
+   * Where `{{outlet}}`s go, when the VM renders this tree as a route
+   * template (see `@glimmer/dom/vm`).
+   */
+  outlets = null;
+  /**
+   * Schedule work that must happen after DOM is inserted
+   * (modifier install/update, component didCreate hooks).
+   */
+  schedule(fn) {
+    this.#queue.push(fn);
+  }
+  flush() {
+    while (this.#queue.length > 0) {
+      let queue = this.#queue;
+      this.#queue = [];
+      for (let fn of queue) fn();
+    }
+  }
+};
+var Block = class {
+  constructor(root, parent) {
+    this.root = root;
+    if (parent) associateDestroyableChild(parent, this);
+  }
+  root;
+  updaters = [];
+  update() {
+    let { updaters } = this;
+    for (let i = 0; i < updaters.length; i++) {
+      updaters[i]();
+    }
+  }
+};
+function marker(root) {
+  return root.document.createTextNode("");
+}
+function mount(parent, before, render) {
+  let b = new Block(parent.root, parent);
+  let start = marker(parent.root);
+  let end = marker(parent.root);
+  let target = before.parentNode;
+  target.insertBefore(start, before);
+  target.insertBefore(render(b), before);
+  target.insertBefore(end, before);
+  return { b, start, end };
+}
+function unmount(m) {
+  removeRange(m.start, m.end);
+  destroy(m.b);
+}
+function removeRange(first, last) {
+  let parent = first.parentNode;
+  if (!parent) return;
+  let node = first;
+  while (node) {
+    let next = node === last ? null : node.nextSibling;
+    parent.removeChild(node);
+    node = next;
+  }
+}
+function moveRange(m, before) {
+  let parent = before.parentNode;
+  let node = m.start;
+  while (node) {
+    let next = node === m.end ? null : node.nextSibling;
+    parent.insertBefore(node, before);
+    node = next;
+  }
+}
+function html(markup) {
+  return { markup, parsed: null };
+}
+function clone(b, t) {
+  let parsed = t.parsed;
+  if (parsed === null) {
+    parsed = t.parsed = b.root.document.createElement("template");
+    parsed.innerHTML = t.markup;
+  }
+  return b.root.document.importNode(parsed.content, true);
+}
+function at(node, ...path) {
+  for (let i of path) {
+    node = node.childNodes[i];
+  }
+  return node;
+}
+var Template = class {
+  constructor(render) {
+    this.render = render;
+  }
+  render;
+  toString() {
+    return "(compiled template)";
+  }
+};
+function template(render) {
+  return new Template(render);
+}
+var TEMPLATES = /* @__PURE__ */ new WeakMap();
+function setTemplate(definition, t) {
+  TEMPLATES.set(definition, t);
+  return definition;
+}
+function templateFor(definition) {
+  if (definition instanceof Template) return definition;
+  let pointer = definition;
+  while (pointer !== null && pointer !== Function.prototype && pointer !== Object.prototype) {
+    let found = TEMPLATES.get(pointer);
+    if (found) return found;
+    pointer = Object.getPrototypeOf(pointer);
+  }
+  return void 0;
+}
+
+// packages/@glimmer/dom/lib/managers.ts
+import { associateDestroyableChild as associateDestroyableChild2, destroy as destroy2 } from "@glimmer/destroyable";
+
+// shim:@glimmer/manager/lib/internal/api
+import { getInternalComponentManager, getInternalHelperManager, getInternalModifierManager } from "@glimmer/manager";
+
+// shim:@glimmer/reference/lib/reference
+import { createComputeRef, valueForRef } from "@glimmer/reference";
+
+// shim:@glimmer/validator/lib/tracking
+import { consumeTag, createCache, getValue, isConst, track, untrack } from "@glimmer/validator";
+
+// shim:@glimmer/validator/lib/validators
+import { createTag, dirtyTag, updateTag, validateTag, valueForTag } from "@glimmer/validator";
+
+// packages/@glimmer/dom/lib/managers.ts
+function capture(named, positional) {
+  let capturedNamed = /* @__PURE__ */ Object.create(null);
+  if (named) {
+    for (let key of Object.keys(named)) {
+      capturedNamed[key] = createComputeRef(named[key]);
+    }
+  }
+  let capturedPositional = (positional ?? []).map((thunk) => createComputeRef(thunk));
+  return {
+    named: capturedNamed,
+    positional: capturedPositional
+  };
+}
+function resolveHelper(definition) {
+  let manager = getInternalHelperManager(definition);
+  return typeof manager === "function" ? manager : manager.getHelper(definition);
+}
+function instantiateHelper(b, definition, args) {
+  let ref = resolveHelper(definition)(args, b.root.owner);
+  associateDestroyableChild2(b, ref);
+  return ref;
+}
+function helper(b, definition, positional, named) {
+  let ref = instantiateHelper(b, definition, capture(named, positional));
+  return () => valueForRef(ref);
+}
+function helperDyn(b, definition, positional, named) {
+  let args = capture(named, positional);
+  let definitionCache = createCache(definition);
+  let current;
+  let ref = null;
+  return () => {
+    let next = getValue(definitionCache);
+    if (next !== current || ref === null) {
+      if (ref !== null) destroy2(ref);
+      current = next;
+      ref = instantiateHelper(b, next, args);
+    }
+    return valueForRef(ref);
+  };
+}
+function modifier(b, element, definition, positional, named) {
+  let manager = getInternalModifierManager(definition);
+  let state = manager.create(
+    b.root.owner,
+    element,
+    definition,
+    capture(named, positional)
+  );
+  let destroyable = manager.getDestroyable(state);
+  if (destroyable) associateDestroyableChild2(b, destroyable);
+  let tag = manager.getTag(state);
+  if (tag === null) {
+    b.root.schedule(() => {
+      manager.install(state);
+    });
+    return;
+  }
+  let lastRevision = null;
+  let run = (hook) => {
+    updateTag(
+      tag,
+      track(() => {
+        hook(state);
+      })
+    );
+    consumeTag(tag);
+    lastRevision = valueForTag(tag);
+  };
+  b.root.schedule(() => {
+    run((s) => {
+      manager.install(s);
+    });
+  });
+  b.updaters.push(() => {
+    consumeTag(tag);
+    if (lastRevision === null || validateTag(tag, lastRevision)) return;
+    lastRevision = null;
+    b.root.schedule(() => {
+      run((s) => {
+        manager.update(s);
+      });
+    });
+  });
+}
+
+// packages/@glimmer/dom/lib/invoke.ts
+import { associateDestroyableChild as associateDestroyableChild3 } from "@glimmer/destroyable";
+
+// shim:@glimmer/manager/lib/public/template
+import { getComponentTemplate, setComponentTemplate } from "@glimmer/manager";
+
+// packages/@glimmer/dom/lib/invoke.ts
+var Curried = class {
+  constructor(definition, named) {
+    this.definition = definition;
+    this.named = named;
+  }
+  definition;
+  named;
+};
+function curry(definition, named) {
+  if (!definition) return null;
+  return new Curried(definition, named ?? {});
+}
+function isComponentDefinition(value) {
+  if (value instanceof Template || value instanceof Curried) return true;
+  if (typeof value !== "object" && typeof value !== "function" || value === null) return false;
+  if (templateFor(value)) return true;
+  return getInternalComponentManager(value, true) !== null;
+}
+var vmFallback = null;
+function setVMFallback(fallback) {
+  vmFallback = fallback;
+}
+function describe(definition) {
+  return typeof definition === "function" ? definition.name || "(anonymous component)" : Object.prototype.toString.call(definition);
+}
+function argsFor(captured) {
+  let args = /* @__PURE__ */ Object.create(null);
+  for (let key of Object.keys(captured.named)) {
+    let ref = captured.named[key];
+    Object.defineProperty(args, key, { enumerable: true, get: () => valueForRef(ref) });
+  }
+  return args;
+}
+function island(b, definition, named, blocks, attrs, current) {
+  if (!vmFallback) {
+    throw new Error(
+      `${describe(definition)} does not have a compiled template. To render it with the VM, import '@glimmer/dom/vm' (or compile with \`vmInterop\`).`
+    );
+  }
+  let element = b.root.document.createElement("glimmer-island");
+  element.style.display = "contents";
+  associateDestroyableChild3(
+    b,
+    vmFallback.render(current ?? (() => definition), element, b.root.owner, {
+      named,
+      blocks,
+      attrs
+    })
+  );
+  return element;
+}
+function instantiate(b, definition, named, blocks, attrs, current) {
+  while (definition instanceof Curried) {
+    named = { ...definition.named, ...named };
+    definition = definition.definition;
+  }
+  let compiled = templateFor(definition);
+  let templateless = !compiled && !getComponentTemplate(definition) && "getDelegateFor" in (getInternalComponentManager(definition, true) ?? {});
+  if (!compiled && !templateless) return island(b, definition, named, blocks, attrs, current);
+  let captured = capture(named, null);
+  let args = argsFor(captured);
+  if (compiled === definition) {
+    return compiled.render(b, { self: void 0, args, blocks, attrs });
+  }
+  let manager = getInternalComponentManager(definition);
+  if (!("getDelegateFor" in manager)) {
+    throw new Error(
+      `Compiled templates can only be used with components that have a custom component manager (like @glimmer/component). ${describe(definition)} does not.`
+    );
+  }
+  let state = manager.create(b.root.owner, definition, { capture: () => captured });
+  let self = valueForRef(manager.getSelf(state));
+  let destroyable = manager.getDestroyable(state);
+  if (destroyable) associateDestroyableChild3(b, destroyable);
+  b.root.schedule(() => {
+    manager.didCreate(state);
+  });
+  if (!compiled) return b.root.document.createDocumentFragment();
+  return compiled.render(b, { self, args, blocks, attrs });
+}
+function invoke(b, anchor, definition, named, blocks, attrs) {
+  let m = mount(b, anchor, (child) => instantiate(child, definition, named, blocks, attrs));
+  b.updaters.push(() => {
+    m.b.update();
+  });
+}
+function invokeDyn(b, anchor, definition, named, blocks, attrs) {
+  let cache = createCache(definition);
+  let current = getValue(cache);
+  let tag = createTag();
+  let read = () => {
+    consumeTag(tag);
+    return current;
+  };
+  let render = (value) => value ? mount(b, anchor, (child) => instantiate(child, value, named, blocks, attrs, read)) : null;
+  let m = render(current);
+  b.updaters.push(() => {
+    let next = getValue(cache);
+    if (next === current) {
+      m?.b.update();
+      return;
+    }
+    if (m && vmFallback?.canUpdate(current, next)) {
+      current = next;
+      dirtyTag(tag);
+      m.b.update();
+      return;
+    }
+    if (m) unmount(m);
+    current = next;
+    m = render(next);
+  });
+}
+
+// packages/@glimmer/dom/lib/render.ts
+import {
+  associateDestroyableChild as associateDestroyableChild4,
+  destroy as destroy3,
+  isDestroying,
+  registerDestructor
+} from "@glimmer/destroyable";
+import { _backburner } from "@ember/runloop";
+function startRoot(owner, document, outlets, build, cleanup) {
+  let root = new Root(owner, document);
+  root.outlets = outlets ?? null;
+  let b = new Block(root, null);
+  let tag;
+  let revision;
+  let destroyed = false;
+  let pass = (fn) => {
+    tag = track(() => {
+      fn();
+      root.flush();
+    });
+    revision = valueForTag(tag);
+  };
+  pass(() => {
+    build(b);
+  });
+  let result;
+  let rerender = () => {
+    if (destroyed || isDestroying(result) || validateTag(tag, revision)) return;
+    pass(() => {
+      b.update();
+    });
+  };
+  _backburner.on("end", rerender);
+  result = {
+    rerender,
+    destroy() {
+      if (destroyed) return;
+      destroyed = true;
+      _backburner.off("end", rerender);
+      cleanup();
+      if (!isDestroying(result)) destroy3(result);
+    }
+  };
+  associateDestroyableChild4(result, b);
+  registerDestructor(result, () => {
+    result.destroy();
+  });
+  return result;
+}
+function renderRoot({ into, owner = {}, outlets }, render) {
+  into.innerHTML = "";
+  let end = into.ownerDocument.createTextNode("");
+  into.appendChild(end);
+  return startRoot(
+    owner,
+    into.ownerDocument,
+    outlets,
+    (b) => {
+      let m = mount(b, end, render);
+      b.updaters.push(() => {
+        m.b.update();
+      });
+    },
+    () => {
+      removeRange(into.firstChild, end);
+    }
+  );
+}
+function attach(element, owner, build) {
+  return startRoot(owner, element.ownerDocument, void 0, build, () => {
+  });
+}
+function renderBlock(block, params, { into, owner }) {
+  return renderRoot({ into, owner }, (child) => block(child, ...params));
+}
+function renderComponent(component, {
+  into,
+  owner,
+  args
+}) {
+  let named = {};
+  if (args) {
+    for (let key of Object.keys(args)) named[key] = () => args[key];
+  }
+  return renderRoot(
+    owner ? { into, owner } : { into },
+    (child) => instantiate(child, component, named, null, null)
+  );
+}
+function renderTemplate(template2, options) {
+  return renderRoot(
+    options,
+    (child) => template2.render(child, { self: options.self, args: options.args, blocks: null, attrs: null })
+  );
+}
+
+export {
+  marker,
+  mount,
+  unmount,
+  removeRange,
+  moveRange,
+  html,
+  clone,
+  at,
+  Template,
+  template,
+  setTemplate,
+  templateFor,
+  consumeTag,
+  createCache,
+  getValue,
+  isConst,
+  untrack,
+  getInternalHelperManager,
+  setComponentTemplate,
+  createComputeRef,
+  valueForRef,
+  createTag,
+  dirtyTag,
+  capture,
+  helper,
+  helperDyn,
+  modifier,
+  curry,
+  isComponentDefinition,
+  setVMFallback,
+  instantiate,
+  invoke,
+  invokeDyn,
+  attach,
+  renderBlock,
+  renderComponent,
+  renderTemplate
+};
diff --git a/packages/ember-repl/src/vendor/glimmer-dom/vm.js b/packages/ember-repl/src/vendor/glimmer-dom/vm.js
new file mode 100644
index 000000000..40a1cdb49
--- /dev/null
+++ b/packages/ember-repl/src/vendor/glimmer-dom/vm.js
@@ -0,0 +1,314 @@
+// @ts-nocheck
+/* eslint-disable */
+/**
+ * VENDORED -- do not edit.
+ *
+ * The runtime for compiled templates (`@glimmer/dom`, `@glimmer/dom/vm`).
+ * Built from https://github.com/NullVoxPopuli-ai-agent/ember.js/tree/claude/gallant-heisenberg-aovzyr (af3aef79),
+ * see https://github.com/emberjs/ember.js/pull/21649
+ *
+ * This is an experiment: strict-mode templates compiled directly to DOM
+ * operations, with no wire format and no VM.
+ */
+import {
+  attach,
+  capture,
+  renderBlock,
+  renderTemplate,
+  setComponentTemplate,
+  setTemplate,
+  setVMFallback,
+  template,
+  templateFor,
+  untrack
+} from "./shared.js";
+
+// packages/@glimmer/dom/lib/vm.ts
+import { registerDestructor as registerDestructor2 } from "@glimmer/destroyable";
+
+// shim:@glimmer/manager/lib/public/component
+import { componentCapabilities } from "@glimmer/manager";
+
+// shim:@glimmer/manager/lib/public/api
+import { setComponentManager, setHelperManager, setModifierManager } from "@glimmer/manager";
+
+// shim:@glimmer/manager/lib/public/modifier
+import { modifierCapabilities } from "@glimmer/manager";
+
+// shim:@glimmer/manager/lib/public/helper
+import { helperCapabilities } from "@glimmer/manager";
+
+// packages/@glimmer/dom/lib/vm.ts
+import { getOwner, setOwner } from "@glimmer/owner";
+
+// shim:@glimmer/constants/lib/curried
+var CURRIED_COMPONENT = 0;
+
+// shim:@glimmer/runtime/lib/curried-value
+import { CurriedValue } from "@glimmer/runtime";
+import { curry } from "@glimmer/runtime";
+var isCurriedValue = (value) => value instanceof CurriedValue;
+
+// shim:@glimmer/validator/lib/collections/array
+import { trackedArray } from "@glimmer/validator";
+
+// shim:@ember/-internals/glimmer/lib/base-renderer
+import { renderComponent } from "@ember/renderer";
+import { registerDestructor } from "@glimmer/destroyable";
+var BaseRenderer = class _BaseRenderer {
+  static strict(owner) {
+    return new _BaseRenderer(owner);
+  }
+  constructor(owner) {
+    this.owner = owner;
+  }
+  render(component, { into, args }) {
+    let result = renderComponent(component, { into, owner: this.owner, args });
+    let destroyable = {};
+    registerDestructor(destroyable, () => result.destroy());
+    return destroyable;
+  }
+};
+
+// packages/@glimmer/dom/lib/vm.ts
+import templateOnly from "@ember/component/template-only";
+import { createTemplateFactory } from "@ember/template-factory";
+var RENDERERS = /* @__PURE__ */ new WeakMap();
+function rendererFor(owner) {
+  let renderer = RENDERERS.get(owner);
+  if (!renderer) {
+    renderer = BaseRenderer.strict(owner, document, {
+      isInteractive: true,
+      hasDOM: true
+    });
+    RENDERERS.set(owner, renderer);
+  }
+  return renderer;
+}
+var ApplyAttrsManager = class {
+  capabilities = modifierCapabilities("3.22");
+  constructor(owner) {
+    this.owner = owner;
+  }
+  createModifier(_definition, args) {
+    return {
+      attrs: args.positional[0],
+      result: null
+    };
+  }
+  installModifier(state, element) {
+    let {
+      attrs
+    } = state;
+    if (attrs) {
+      state.result = attach(element, this.owner, (b) => {
+        attrs(b, element);
+      });
+    }
+  }
+  updateModifier() {
+  }
+  destroyModifier(state) {
+    state.result?.destroy();
+  }
+};
+var applyAttrs = setModifierManager((owner) => new ApplyAttrsManager(owner), {});
+var BlockIslandManager = class {
+  capabilities = helperCapabilities("3.23", {
+    hasValue: true,
+    hasDestroyable: true
+  });
+  constructor(owner) {
+    this.owner = owner;
+  }
+  createHelper(_definition, args) {
+    let block = args.positional[0];
+    let params = [1, 2, 3].map((i) => () => args.positional[i]);
+    return untrack(() => {
+      let element = document.createElement("glimmer-island");
+      element.style.display = "contents";
+      let result = renderBlock(block, params, {
+        into: element,
+        owner: this.owner
+      });
+      return {
+        element,
+        result
+      };
+    });
+  }
+  getValue(island2) {
+    return island2.element;
+  }
+  getDestroyable(island2) {
+    return island2.result;
+  }
+};
+var blockIsland = setHelperManager((owner) => new BlockIslandManager(owner ?? {}), {});
+var INVOKE = setComponentTemplate(createTemplateFactory(
+  /*
+    {{#if @block}}<@definition {{applyAttrs @attrs}} as |a b c|>{{blockIsland @block a b c}}</@definition>{{else}}<@definition {{applyAttrs @attrs}} />{{/if}}
+  */
+  {
+    "id": null,
+    "block": '[[[41,[30,1],[[[8,[30,2],[[4,[32,0],[[30,3]],null]],null,[["default"],[[[[1,[28,[32,1],[[30,1],[30,4],[30,5],[30,6]],null]]],[4,5,6]]]]]],[]],[[[8,[30,2],[[4,[32,0],[[30,3]],null]],null,null]],[]]]],["@block","@definition","@attrs","a","b","c"],["if"]]',
+    "moduleName": "packages/@glimmer/dom/lib/invoke.hbs",
+    "scope": () => ({
+      applyAttrs,
+      blockIsland
+    }),
+    "isStrictMode": true
+  }
+), templateOnly());
+setVMFallback({
+  render(definition, into, owner, {
+    named,
+    blocks,
+    attrs
+  }) {
+    let args = capture(named, null);
+    let last;
+    let curried;
+    return rendererFor(owner).render(INVOKE, {
+      into,
+      args: {
+        get definition() {
+          let value = definition();
+          if (value !== last || !curried) {
+            last = value;
+            curried = curry(CURRIED_COMPONENT, value, owner, args);
+          }
+          return curried;
+        },
+        attrs,
+        block: blocks?.["default"] ?? null
+      }
+    });
+  },
+  canUpdate(from, to) {
+    return isCurriedValue(from) && isCurriedValue(to);
+  }
+});
+var TemplateOnlyState = class {
+  constructor(template3, args) {
+    this.template = template3;
+    this.args = args;
+  }
+};
+function createIsland(context) {
+  return untrack(() => {
+    let template3;
+    let self;
+    let args;
+    if (context instanceof TemplateOnlyState) {
+      template3 = context.template;
+      self = void 0;
+      args = context.args;
+    } else {
+      template3 = templateFor(context.constructor);
+      self = context;
+      args = context.args ?? {};
+    }
+    if (!template3) {
+      throw new Error("BUG: rendering a compiled component without a compiled template");
+    }
+    let element = document.createElement("glimmer-island");
+    element.style.display = "contents";
+    let outlets = trackedArray([]);
+    let result = renderTemplate(template3, {
+      into: element,
+      owner: getOwner(context) ?? {},
+      self,
+      args,
+      outlets: {
+        add(outlet2) {
+          outlets.push(outlet2);
+          return () => {
+            let index = outlets.indexOf(outlet2);
+            if (index !== -1) outlets.splice(index, 1);
+          };
+        }
+      }
+    });
+    return {
+      element,
+      outlets,
+      result
+    };
+  });
+}
+var IslandHelperManager = class {
+  capabilities = helperCapabilities("3.23", {
+    hasValue: true,
+    hasDestroyable: true
+  });
+  createHelper(_definition, args) {
+    return createIsland(args.positional[0]);
+  }
+  getValue(island2) {
+    return island2;
+  }
+  getDestroyable(island2) {
+    return island2.result;
+  }
+};
+var island = setHelperManager(() => new IslandHelperManager(), {});
+var BRIDGE = createTemplateFactory(
+  /*
+    {{#let (island this) as |i|}}{{i.element}}{{#each i.outlets as |el|}}{{#in-element el insertBefore=null}}<@outlet />{{/in-element}}{{/each}}{{/let}}
+  */
+  {
+    "id": null,
+    "block": '[[[44,[[28,[32,0],[[30,0]],null]],[[[1,[30,1,["element"]]],[42,[28,[31,2],[[28,[31,2],[[30,1,["outlets"]]],null]],null],null,[[[40,[[[8,[30,3],null,null,null]],[]],"%cursor:0%",[28,[31,4],[[30,2]],null],null]],[2]],null]],[1]]]],["i","el","@outlet"],["let","each","-track-array","in-element","-in-el-null"]]',
+    "moduleName": "packages/@glimmer/dom/lib/vm.hbs",
+    "scope": () => ({
+      island
+    }),
+    "isStrictMode": true
+  }
+);
+var CAPABILITIES = componentCapabilities("3.13", {});
+var TemplateOnlyManager = class {
+  capabilities = CAPABILITIES;
+  constructor(owner) {
+    this.owner = owner;
+  }
+  createComponent(definition, args) {
+    let state = new TemplateOnlyState(definition, args.named);
+    setOwner(state, this.owner);
+    return state;
+  }
+  getContext(state) {
+    return state;
+  }
+};
+function vmCompatible(t) {
+  setComponentManager((owner) => new TemplateOnlyManager(owner), t);
+  setComponentTemplate(BRIDGE, t);
+  return t;
+}
+function template2(render) {
+  return vmCompatible(template(render));
+}
+function setTemplate2(definition, t) {
+  setTemplate(definition, t);
+  setComponentTemplate(BRIDGE, definition);
+  return definition;
+}
+function outlet(b, anchor) {
+  let sink = b.root.outlets;
+  if (!sink) {
+    throw new Error("{{outlet}} can only be used in a template that the router renders (a route template)");
+  }
+  let element = b.root.document.createElement("glimmer-outlet");
+  element.style.display = "contents";
+  anchor.parentNode.insertBefore(element, anchor);
+  let remove = sink.add(element);
+  registerDestructor2(b, remove);
+}
+export {
+  outlet,
+  setTemplate2 as setTemplate,
+  template2 as template,
+  vmCompatible
+};
diff --git a/packages/repl-sdk/src/compilers/ember/gjs.js b/packages/repl-sdk/src/compilers/ember/gjs.js
index dee8f19eb..a0876ecfd 100644
--- a/packages/repl-sdk/src/compilers/ember/gjs.js
+++ b/packages/repl-sdk/src/compilers/ember/gjs.js
@@ -90,14 +90,21 @@ export async function compiler(config, api, flags = {}) {
 
   const babel = 'availablePlugins' in _babel ? _babel : _babel.default;
 
+  const codegenCompiler = codegen ? await import('./vendor/codegen-compiler.js') : null;
   /**
    * @type {unknown[]}
    */
-  const templatePlugin = codegen
+  const templatePlugin = codegenCompiler
     ? [
-        (await import('./vendor/codegen-compiler.js')).codegenBabelPlugin,
-        // the parser that ships with ember-source
-        { preprocess: compiler._preprocess },
+        codegenCompiler.codegenBabelPlugin,
+        {
+          // the parser that ships with ember-source
+          preprocess: compiler._preprocess,
+          // compiled components can be rendered by the VM too (and VM-only
+          // components, e.g. from addons, by compiled templates)
+          vmInterop: true,
+          isGlobal: codegenCompiler.isAllowedGlobal,
+        },
       ]
     : [
         emberTemplateCompilation,
diff --git a/packages/repl-sdk/src/compilers/ember/vendor/codegen-compiler.js b/packages/repl-sdk/src/compilers/ember/vendor/codegen-compiler.js
index 253a33ccd..499593f4d 100644
--- a/packages/repl-sdk/src/compilers/ember/vendor/codegen-compiler.js
+++ b/packages/repl-sdk/src/compilers/ember/vendor/codegen-compiler.js
@@ -4,7 +4,8 @@
  * VENDORED -- do not edit.
  *
  * The template compiler for the codegen flavor (babel plugin + code generator).
- * Built from https://github.com/NullVoxPopuli-ai-agent/ember.js/tree/claude/gallant-heisenberg-aovzyr (2b03eb8).
+ * Built from https://github.com/NullVoxPopuli-ai-agent/ember.js/tree/claude/gallant-heisenberg-aovzyr (af3aef79),
+ * see https://github.com/emberjs/ember.js/pull/21649
  *
  * This is an experiment: strict-mode templates compiled directly to DOM
  * operations, with no wire format and no VM.
@@ -80,6 +81,7 @@ var SPECIALIZED = {
     "and",
     "array",
     "concat",
+    "element",
     "eq",
     "fn",
     "get",
@@ -345,12 +347,9 @@ ${children}`;
     let builtin = this.builtin(node.path, body.scope);
     if (builtin === "on") {
       let [event, handler] = node.params;
-      if (!event || !handler) {
-        throw new CodegenError("`on` requires an event name and a handler", node);
-      }
       let options = node.hash.pairs.length ? `, { ${node.hash.pairs.map((p) => `${key(p.key)}: ${this.expr(p.value, body)}`).join(", ")} }` : "";
       body.lines.push(
-        `${this.rt("listen")}($_b, ${element}, ${this.expr(event, body)}, () => ${this.expr(handler, body)}${options});`
+        `${this.rt("listen")}($_b, ${element}, ${event ? this.expr(event, body) : "undefined"}, () => ${handler ? this.expr(handler, body) : "undefined"}${options});`
       );
       return;
     }
@@ -405,6 +404,15 @@ ${children}`;
       case "debugger":
         body.lines.push("debugger;");
         return;
+      case "outlet":
+        if (this.options.vmInterop) {
+          body.lines.push(`${this.rt("outlet")}($_b, ${anchor});`);
+        } else {
+          body.lines.push(
+            `${this.rt("invokeDyn")}($_b, ${anchor}, () => $_a.outlet, {}, null, null);`
+          );
+        }
+        return;
       case "component": {
         let [definition, ...rest] = params;
         if (!definition) throw new CodegenError("`{{component}}` requires a component", node);
@@ -673,6 +681,8 @@ ${inner.lines.join("\n")}
           base = head.name;
         } else if (head.name in AUTO_IMPORTED) {
           base = this.options.importBinding(AUTO_IMPORTED[head.name], head.name);
+        } else if (this.options.isGlobal?.(head.name)) {
+          base = head.name;
         } else {
           throw new CodegenError(
             `Attempted to use \`${head.name}\`, but it is not in scope. In strict mode, values must be imported or defined in JavaScript`,
@@ -744,7 +754,7 @@ ${inner.lines.join("\n")}
       case "log":
         return `${this.rt("log")}(${all().join(", ")})`;
       case "element":
-        break;
+        return `${this.rt("element")}(${arg(0)})`;
       default:
         throw new CodegenError(`\`${builtin}\` is not supported by the codegen compiler yet`, node);
     }
@@ -787,6 +797,7 @@ function generate(ast, options) {
 }
 
 // packages/@glimmer/compiler/lib/codegen/babel-plugin.ts
+var VM_RUNTIME = /* @__PURE__ */ new Set(["outlet", "setTemplate", "template"]);
 var TEMPLATE_MODULES = /* @__PURE__ */ new Set(["@ember/template-compiler", "@ember/template-compiler/runtime"]);
 function importedName(specifier) {
   return specifier.imported.type === "StringLiteral" ? specifier.imported.value : specifier.imported.name;
@@ -794,107 +805,177 @@ function importedName(specifier) {
 function codegenBabelPlugin(babel, options) {
   let t = babel.types;
   let runtimeModule = options.runtimeModule ?? "@glimmer/dom";
-  return {
-    name: "glimmer-codegen",
-    visitor: {
-      Program: {
-        enter(_path, state) {
-          state.codegen = { imports: /* @__PURE__ */ new Map(), hoisted: [], templates: 0 };
-        },
-        exit(path, state) {
-          let { imports, hoisted } = state.codegen;
-          if (imports.size === 0) return;
-          let declarations = [...imports].map(
-            ([module, names]) => t.importDeclaration(
-              [...names].map(
-                ([name, local]) => t.importSpecifier(t.identifier(local), t.identifier(name))
-              ),
-              t.stringLiteral(module)
-            )
-          );
-          let statements = hoisted.flatMap(
-            (code) => babel.template.statements.ast(code, { placeholderPattern: false })
-          );
-          path.unshiftContainer("body", [...declarations, ...statements]);
-          path.scope.crawl();
-          for (let statement of path.get("body")) {
-            if (!statement.isImportDeclaration()) continue;
-            if (!TEMPLATE_MODULES.has(statement.node.source.value)) continue;
-            for (let specifier of statement.get("specifiers")) {
-              let binding = path.scope.getBinding(specifier.node.local.name);
-              if (binding && !binding.referenced) specifier.remove();
-            }
-            if (statement.node.specifiers.length === 0) statement.remove();
-          }
-        }
-      },
-      CallExpression(path, state) {
-        let callee = path.get("callee");
-        if (!callee.isIdentifier()) return;
-        let binding = path.scope.getBinding(callee.node.name);
-        if (!binding || binding.kind !== "module" || !binding.path.isImportSpecifier()) return;
-        if (!TEMPLATE_MODULES.has(binding.path.parent.source.value)) return;
-        if (importedName(binding.path.node) !== "template") return;
-        let [source, templateOptions] = path.node.arguments;
-        let text;
-        if (t.isTemplateLiteral(source) && source.expressions.length === 0) {
-          text = source.quasis[0].value.cooked;
-        } else if (t.isStringLiteral(source)) {
-          text = source.value;
-        } else {
-          throw path.buildCodeFrameError("template() must be called with a static string");
-        }
-        let component = null;
-        if (templateOptions && t.isObjectExpression(templateOptions)) {
-          for (let property of templateOptions.properties) {
-            if (t.isObjectProperty(property) && t.isIdentifier(property.key, { name: "component" })) {
-              component = property.value;
-            }
-          }
-        }
-        let program = path.scope.getProgramParent();
-        let { imports } = state.codegen;
-        let local = (module, name) => {
-          let names = imports.get(module);
-          if (!names) imports.set(module, names = /* @__PURE__ */ new Map());
-          let existing = names.get(name);
-          if (existing) return existing;
-          let id = program.generateUid(name.replace(/\W/gu, "_"));
-          names.set(name, id);
-          return id;
-        };
-        let importOf = (name) => {
-          let found = path.scope.getBinding(name);
-          if (!found || found.kind !== "module") return void 0;
-          let module = found.path.parent.source.value;
-          if (found.path.isImportSpecifier())
-            return { module, name: importedName(found.path.node) };
-          if (found.path.isImportDefaultSpecifier()) return { module, name: "default" };
-          return void 0;
-        };
-        let ast = options.preprocess(text, { strictMode: true });
-        let { hoisted, expression } = generate(ast, {
-          isLexical: (name) => Boolean(path.scope.getBinding(name)),
-          importOf,
-          runtime: (name) => local(runtimeModule, name),
-          importBinding: local,
-          prefix: `${state.codegen.templates++}_`
-        });
-        state.codegen.hoisted.push(...hoisted);
-        let replacement = babel.template.expression.ast(expression, { placeholderPattern: false });
-        if (component) {
-          replacement = t.callExpression(t.identifier(local(runtimeModule, "setTemplate")), [
-            component,
-            replacement
-          ]);
+  let vmInterop = options.vmInterop ?? false;
+  let moduleFor = (name) => vmInterop && VM_RUNTIME.has(name) ? `${runtimeModule}/vm` : runtimeModule;
+  let compileTemplate = (path, state) => {
+    let callee = path.get("callee");
+    if (!callee.isIdentifier()) return;
+    let binding = path.scope.getBinding(callee.node.name);
+    if (!binding || binding.kind !== "module" || !binding.path.isImportSpecifier()) return;
+    if (!TEMPLATE_MODULES.has(binding.path.parent.source.value)) return;
+    if (importedName(binding.path.node) !== "template") return;
+    let [source, templateOptions] = path.node.arguments;
+    let text;
+    if (t.isTemplateLiteral(source) && source.expressions.length === 0) {
+      text = source.quasis[0].value.cooked;
+    } else if (t.isStringLiteral(source)) {
+      text = source.value;
+    } else {
+      throw path.buildCodeFrameError("template() must be called with a static string");
+    }
+    let component = null;
+    if (templateOptions && t.isObjectExpression(templateOptions)) {
+      for (let property of templateOptions.properties) {
+        if (t.isObjectProperty(property) && t.isIdentifier(property.key, { name: "component" })) {
+          component = property.value;
         }
-        path.replaceWith(replacement);
       }
     }
+    let program = path.scope.getProgramParent();
+    let { imports } = state.codegen;
+    let local = (module, name) => {
+      let names = imports.get(module);
+      if (!names) imports.set(module, names = /* @__PURE__ */ new Map());
+      let existing = names.get(name);
+      if (existing) return existing;
+      let id = program.generateUid(name.replace(/\W/gu, "_"));
+      names.set(name, id);
+      return id;
+    };
+    let importOf = (name) => {
+      let found = path.scope.getBinding(name);
+      if (!found || found.kind !== "module") return void 0;
+      let module = found.path.parent.source.value;
+      if (found.path.isImportSpecifier()) return { module, name: importedName(found.path.node) };
+      if (found.path.isImportDefaultSpecifier()) return { module, name: "default" };
+      return void 0;
+    };
+    let ast = options.preprocess(text, { strictMode: true });
+    let { hoisted, expression } = generate(ast, {
+      isLexical: (name) => Boolean(path.scope.getBinding(name)),
+      importOf,
+      runtime: (name) => local(moduleFor(name), name),
+      importBinding: local,
+      prefix: `${state.codegen.templates++}_`,
+      vmInterop,
+      ...options.isGlobal ? { isGlobal: options.isGlobal } : {}
+    });
+    state.codegen.hoisted.push(...hoisted);
+    let replacement = babel.template.expression.ast(expression, { placeholderPattern: false });
+    if (component) {
+      replacement = t.callExpression(t.identifier(local(moduleFor("setTemplate"), "setTemplate")), [
+        component,
+        replacement
+      ]);
+    }
+    path.replaceWith(replacement);
+  };
+  let addImports = (path, state) => {
+    let { imports, hoisted } = state.codegen;
+    if (imports.size === 0) return;
+    let declarations = [...imports].map(
+      ([module, names]) => t.importDeclaration(
+        [...names].map(
+          ([name, local]) => t.importSpecifier(t.identifier(local), t.identifier(name))
+        ),
+        t.stringLiteral(module)
+      )
+    );
+    let statements = hoisted.flatMap(
+      (code) => babel.template.statements.ast(code, { placeholderPattern: false })
+    );
+    path.unshiftContainer("body", [...declarations, ...statements]);
+    path.scope.crawl();
+    for (let statement of path.get("body")) {
+      if (!statement.isImportDeclaration()) continue;
+      if (!TEMPLATE_MODULES.has(statement.node.source.value)) continue;
+      for (let specifier of statement.get("specifiers")) {
+        let binding = path.scope.getBinding(specifier.node.local.name);
+        if (binding && !binding.referenced) specifier.remove();
+      }
+      if (statement.node.specifiers.length === 0) statement.remove();
+    }
+  };
+  return {
+    name: "glimmer-codegen",
+    // Everything happens in `pre` (rather than in a visitor), so that this
+    // plugin compiles `template()` before other template plugins see it
+    // (babel-plugin-ember-template-compilation also does its work in `pre`).
+    // List this plugin first.
+    pre(file) {
+      this.codegen = { imports: /* @__PURE__ */ new Map(), hoisted: [], templates: 0 };
+      file.path.traverse(
+        {
+          CallExpression: (call) => {
+            compileTemplate(call, this);
+          }
+        },
+        this
+      );
+      addImports(file.path, this);
+    },
+    visitor: {}
   };
 }
+
+// packages/@ember/template-compiler/lib/plugins/allowed-globals.ts
+var ALLOWED_GLOBALS = /* @__PURE__ */ new Set([
+  // ////////////////
+  // namespaces
+  // ////////////////
+  //   TC39
+  "globalThis",
+  "Atomics",
+  "JSON",
+  "Math",
+  "Reflect",
+  //   WHATWG
+  "localStorage",
+  "sessionStorage",
+  "URL",
+  // ////////////////
+  // functions / utilities
+  // ////////////////
+  //   TC39
+  "isNaN",
+  "isFinite",
+  "parseInt",
+  "parseFloat",
+  "decodeURI",
+  "decodeURIComponent",
+  "encodeURI",
+  "encodeURIComponent",
+  //   WHATWG
+  "postMessage",
+  "structuredClone",
+  // ////////////////
+  // new-less Constructors (still functions)
+  // ////////////////
+  //   TC39
+  "Array",
+  // different behavior from (array)
+  "BigInt",
+  "Boolean",
+  "Date",
+  "Number",
+  "Object",
+  // different behavior from (hash)
+  "String",
+  // ////////////////
+  // Values
+  // ////////////////
+  //   TC39
+  "Infinity",
+  "NaN",
+  //   WHATWG
+  "isSecureContext"
+]);
+
+// <stdin>
+var isAllowedGlobal = (name) => ALLOWED_GLOBALS.has(name);
 export {
   CodegenError,
   codegenBabelPlugin,
-  generate
+  generate,
+  isAllowedGlobal
 };