Add deprecation guide for using-amd-bundles

content/ember/v6/using-amd-bundles.md

@@ -0,0 +1,34 @@
+---
+title: Using `amd` bundles
+until: 7.0.0
+since: 6.10.0
+rfc: https://rfcs.emberjs.com/id/1101-deprecate-ember-vendor-bundles
+---
+
+Ember will no longer publish legacy AMD-specific Ember builds. To opt-in to
+consuming Ember as ES modules and clear this deprecation, enable the
+`ember-modules` optional feature by running `ember feature:enable ember-modules`.
+
+This applies only to the classic build system or to Embroider < 4.0 without the
+`staticEmberSource: true` option. If you see this deprecation warning in these
+setups, please [open an issue](https://github.com/emberjs/ember.js/issues/new/choose).
+
+Alternatively, you can also clear the deprecation by moving to Embroider v4 by
+running the [Ember Vite Codemod](https://github.com/mainmatter/ember-vite-codemod),
+but this may require additional changes to your project.
+
+The AMD-specific Ember builds will no longer be published in next Ember major release
+and no longer be bundled into `vendor.js`, even on the classic build system. These files are:
+-
+- `ember.debug.js`
+- `ember.prod.js`
+- `ember-testing.js`
+- `ember-template-compiler.js`
+
+- In rare cases, Addons were relying on accessing Ember from `vendor`. If you have
+  addons that do so they will need to be updated to consume Ember as ES modules.
+
+A known addon that previously relied on accessing Ember from `vendor` is
+[ember-cli-deprecation-workflow](https://github.com/ember-cli/ember-cli-deprecation-workflow).
+Please ensure you are on the latest version of this addon as that reliance has
+been removed.