diff --git a/package-lock.json b/package-lock.json
index dd3db5c..15323f4 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "@codebar-ag/storybook",
-  "version": "1.8.0",
+  "version": "1.9.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "@codebar-ag/storybook",
-      "version": "1.8.0",
+      "version": "1.9.0",
       "license": "MIT",
       "dependencies": {
         "@fontsource/jetbrains-mono": "^5.3.0",
@@ -40,6 +40,13 @@
         "vue-tsc": "^3.3.7"
       },
       "peerDependencies": {
+        "@codemirror/commands": "^6.10.0",
+        "@codemirror/lang-json": "^6.0.0",
+        "@codemirror/lang-markdown": "^6.5.0",
+        "@codemirror/language": "^6.12.0",
+        "@codemirror/state": "^6.7.0",
+        "@codemirror/view": "^6.43.0",
+        "apexcharts": "^4.5.0 || ^5.0.0",
         "tailwindcss": "^4.0.0",
         "vue": "^3.5.0"
       },
diff --git a/package.json b/package.json
index cd263bd..675fbcc 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@codebar-ag/storybook",
-  "version": "1.8.0",
+  "version": "1.9.0",
   "description": "codebar-ag DocuHub — shared Vue 3 + Tailwind v4 design-system atoms and tokens, documented in Storybook.",
   "license": "MIT",
   "author": "codebar Solutions AG",
@@ -25,7 +25,8 @@
   "scripts": {
     "prepare": "npm run build",
     "dev": "storybook dev -p 6006",
-    "build": "vite build && npm run build:tokens",
+    "build": "vite build && npm run build:tokens && npm run verify:externals",
+    "verify:externals": "node scripts/verify-externals.mjs",
     "build:tokens": "node -e \"require('node:fs').copyFileSync('src/tokens.css','dist/tokens.css')\"",
     "build-storybook": "storybook build",
     "lint": "eslint \"src/**/*.{ts,vue}\"",
@@ -39,7 +40,14 @@
   },
   "peerDependencies": {
     "tailwindcss": "^4.0.0",
-    "vue": "^3.5.0"
+    "vue": "^3.5.0",
+    "apexcharts": "^4.5.0 || ^5.0.0",
+    "@codemirror/commands": "^6.10.0",
+    "@codemirror/lang-json": "^6.0.0",
+    "@codemirror/lang-markdown": "^6.5.0",
+    "@codemirror/language": "^6.12.0",
+    "@codemirror/state": "^6.7.0",
+    "@codemirror/view": "^6.43.0"
   },
   "peerDependenciesMeta": {
     "apexcharts": {
diff --git a/scripts/verify-externals.mjs b/scripts/verify-externals.mjs
new file mode 100644
index 0000000..f3273b0
--- /dev/null
+++ b/scripts/verify-externals.mjs
@@ -0,0 +1,39 @@
+// Guards the library build's externalisation contract, which nothing else can.
+//
+// Storybook and its Playwright suite compile from `src`, so they always see a
+// single copy of every dependency — they cannot observe what the PUBLISHED
+// bundle does. If a peer package is missing from `rollupOptions.external`,
+// Rollup quietly inlines it into an extra chunk and the consumer ends up with
+// two instances of it. For `@codemirror/language` that means the parser
+// registers its syntax tree against one set of facets while
+// `syntaxHighlighting()` reads the other, and every code surface in every
+// consuming app renders as flat, unhighlighted text — with no error anywhere.
+//
+// The observable symptom in `dist` is an extra chunk file plus a relative
+// import out of `flows.js`, so both are asserted here.
+import { readdirSync, readFileSync } from 'node:fs';
+
+const EXPECTED_FILES = ['flows.css', 'flows.js', 'index.d.ts', 'tokens.css'];
+
+const actual = readdirSync('dist').sort();
+const unexpected = actual.filter((file) => !EXPECTED_FILES.includes(file));
+
+if (unexpected.length > 0) {
+    console.error(
+        `dist/ has unexpected chunk(s): ${unexpected.join(', ')}\n` +
+            'A dependency was bundled instead of externalised. Add it to ' +
+            "`rollupOptions.external` in vite.config.ts (and to `peerDependencies`).",
+    );
+    process.exit(1);
+}
+
+const bundle = readFileSync('dist/flows.js', 'utf8');
+const relativeImports = [...bundle.matchAll(/(?:from|import\()\s*["'](\.[^"']*)["']/g)].map((match) => match[1]);
+
+if (relativeImports.length > 0) {
+    console.error(
+        `dist/flows.js imports emitted chunk(s): ${[...new Set(relativeImports)].join(', ')}\n` +
+            'Every dependency must resolve to a bare specifier so the consuming app supplies one copy.',
+    );
+    process.exit(1);
+}
diff --git a/src/components/organisms/CodeEditor.stories.ts b/src/components/organisms/CodeEditor.stories.ts
index 968cb02..29f1ded 100644
--- a/src/components/organisms/CodeEditor.stories.ts
+++ b/src/components/organisms/CodeEditor.stories.ts
@@ -1,6 +1,35 @@
 import type { Meta, StoryObj } from '@storybook/vue3-vite';
+import { expect, waitFor } from 'storybook/test';
 import CodeEditor from './CodeEditor.vue';
 
+/**
+ * Asserts the document is actually SYNTAX HIGHLIGHTED, not merely rendered.
+ *
+ * This guards a failure mode with no error signal: if the library build ever
+ * bundles `@codemirror/language` instead of externalising it, the consumer
+ * loads two copies of it, the language's syntax tree registers against one
+ * set of facets and `syntaxHighlighting()` reads the other, and every editor
+ * silently renders as flat monochrome text.
+ *
+ * The check is "some token is painted a colour other than the body text's",
+ * not "tokens use more than one colour between them": a short JSON document
+ * may legitimately contain only one *styled* tag kind (`defaultHighlightStyle`
+ * leaves plain `propertyName` uncoloured), which would make a colour-diversity
+ * assertion fail on working code.
+ */
+async function expectHighlighted(canvasElement: HTMLElement): Promise<void> {
+    await waitFor(async () => {
+        const content = canvasElement.querySelector('.cm-content');
+        await expect(content).not.toBeNull();
+
+        const tokens = canvasElement.querySelectorAll('.cm-line span');
+        await expect(tokens.length).toBeGreaterThan(0);
+
+        const base = getComputedStyle(content as Element).color;
+        await expect([...tokens].some((token) => getComputedStyle(token).color !== base)).toBe(true);
+    });
+}
+
 const meta: Meta<typeof CodeEditor> = {
     title: 'Organisms/CodeEditor',
     component: CodeEditor,
@@ -19,13 +48,16 @@ const meta: Meta<typeof CodeEditor> = {
 export default meta;
 type Story = StoryObj<typeof CodeEditor>;
 
-export const Json: Story = {};
+export const Json: Story = {
+    play: ({ canvasElement }) => expectHighlighted(canvasElement),
+};
 
 export const Markdown: Story = {
     args: {
-        modelValue: '# Extraction prompt\n\nSummarize the invoice fields below.',
+        modelValue: '# Extraction prompt\n\nSummarize the **invoice** fields below.',
         language: 'markdown',
     },
+    play: ({ canvasElement }) => expectHighlighted(canvasElement),
 };
 
 export const ReadOnlyEmpty: Story = {
@@ -38,3 +70,7 @@ export const ReadOnlyEmpty: Story = {
 export const AutoHeight: Story = {
     args: { autoHeight: true, maxHeight: '12rem' },
 };
+
+export const Copyable: Story = {
+    args: { copyable: true, readonly: true },
+};
diff --git a/src/components/organisms/CodeEditor.vue b/src/components/organisms/CodeEditor.vue
index 7a8fd4e..2fb8e60 100644
--- a/src/components/organisms/CodeEditor.vue
+++ b/src/components/organisms/CodeEditor.vue
@@ -1,7 +1,8 @@
 <script setup lang="ts">
-import { onBeforeUnmount, onMounted, ref, watch } from 'vue';
+import { computed, onBeforeUnmount, onMounted, ref, watch } from 'vue';
 import type { EditorView as EditorViewType } from '@codemirror/view';
 import { createCodeMirrorTheme } from '../../helpers/codeMirrorTheme';
+import CopyButton from '../molecules/CopyButton.vue';
 
 // CodeMirror is an OPTIONAL peer dependency: it is imported lazily so apps
 // that never render an editor don't pay for the bundle (same convention as
@@ -16,6 +17,10 @@ const props = withDefaults(
         placeholder?: string | null;
         autoHeight?: boolean;
         maxHeight?: string | null;
+        /** Pins a copy-to-clipboard button over the top-right of the editor. Opt-in, so existing surfaces keep their chrome. */
+        copyable?: boolean;
+        copyLabel?: string;
+        copiedMessage?: string;
     }>(),
     {
         modelValue: '',
@@ -24,6 +29,9 @@ const props = withDefaults(
         placeholder: null,
         autoHeight: false,
         maxHeight: null,
+        copyable: false,
+        copyLabel: 'Copy to clipboard',
+        copiedMessage: 'Copied to clipboard',
     },
 );
 
@@ -44,6 +52,10 @@ function formatValue(raw: string): string {
     }
 }
 
+// Copies what the operator can actually see — the pretty-printed document,
+// not the raw (often single-line) `modelValue` handed in by the caller.
+const copyValue = computed(() => formatValue(props.modelValue ?? ''));
+
 async function loadLanguage(language: string) {
     if (language === 'markdown') {
         const { markdown, markdownLanguage } = await import('@codemirror/lang-markdown');
@@ -140,6 +152,23 @@ onBeforeUnmount(() => view?.destroy());
     :class="autoHeight ? 'overflow-y-auto' : 'h-full min-h-0 overflow-hidden'"
     :style="autoHeight && maxHeight ? { maxHeight } : undefined"
   >
+    <!--
+      Sticky rather than absolute, and zero-height so it claims no layout: in
+      `autoHeight` mode THIS element is the scroll container, and an absolutely
+      positioned child would scroll out of sight on any document longer than
+      the visible box.
+    -->
+    <div
+      v-if="copyable && modelValue"
+      class="sticky top-0 z-10 flex h-0 justify-end"
+    >
+      <CopyButton
+        :value="copyValue"
+        :label="copyLabel"
+        :copied-message="copiedMessage"
+        class="mt-1.5 mr-1.5 rounded-control border border-line bg-surface/90 text-dim backdrop-blur-sm hover:text-ink focus-visible:ring-accent/50"
+      />
+    </div>
     <div
       v-if="!modelValue && readonly && placeholder"
       :class="autoHeight ? 'flex min-h-16 items-center justify-center' : 'pointer-events-none absolute inset-0 flex items-center justify-center'"
diff --git a/src/components/organisms/CodePreview.vue b/src/components/organisms/CodePreview.vue
index 3506d03..e36ae9a 100644
--- a/src/components/organisms/CodePreview.vue
+++ b/src/components/organisms/CodePreview.vue
@@ -55,9 +55,10 @@ async function mount(): Promise<void> {
         return;
     }
 
-    const [{ EditorState }, EditorViewModule, lang] = await Promise.all([
+    const [{ EditorState }, EditorViewModule, { syntaxHighlighting, defaultHighlightStyle }, lang] = await Promise.all([
         import('@codemirror/state'),
         import('@codemirror/view'),
+        import('@codemirror/language'),
         loadLanguage(props.language),
     ]);
     const { EditorView, lineNumbers } = EditorViewModule;
@@ -76,6 +77,10 @@ async function mount(): Promise<void> {
                 EditorView.lineWrapping,
                 lineNumbers(),
                 lang,
+                // Same highlighter as CodeEditor — a preview surface that
+                // renders code as flat grey text is the one thing it exists
+                // not to do.
+                syntaxHighlighting(defaultHighlightStyle, { fallback: true }),
                 // Shared theme (same as CodeEditor) plus this component's own
                 // maxHeight cap, which only makes sense for a preview surface.
                 createCodeMirrorTheme(EditorViewModule, { autoHeight: true }),
diff --git a/tests/interactions.spec.ts b/tests/interactions.spec.ts
index 0ff21a7..c598778 100644
--- a/tests/interactions.spec.ts
+++ b/tests/interactions.spec.ts
@@ -28,3 +28,16 @@ test('copy button writes to the clipboard and toasts', async ({ page, context })
     await page.getByRole('button', { name: 'Copy to clipboard' }).first().click();
     await expect(page.getByText('Copied to clipboard').first()).toBeVisible();
 });
+
+test('a copyable code editor copies the document it displays', async ({ page, context }) => {
+    await context.grantPermissions(['clipboard-read', 'clipboard-write']);
+    await gotoStory(page, 'organisms-codeeditor--copyable');
+    await expect(page.locator('.cm-content')).toBeVisible();
+    await page.getByRole('button', { name: 'Copy to clipboard' }).click();
+
+    // Only the clipboard write is asserted here — the story renders no Toaster,
+    // and the toast itself is already covered by the CopyButton test above.
+    // The pretty-printed document, not whatever shape the caller passed in.
+    const clipboard = await page.evaluate(() => navigator.clipboard.readText());
+    expect(clipboard).toBe('{\n  "vendor": "string",\n  "invoice_number": "string"\n}');
+});
diff --git a/vite.config.ts b/vite.config.ts
index 47778d0..525c779 100644
--- a/vite.config.ts
+++ b/vite.config.ts
@@ -30,11 +30,22 @@ export default defineConfig({
             formats: ['es'],
         },
         rollupOptions: {
+            // EVERY @codemirror/* package must be listed here, not just the
+            // ones imported by name in a component. `@codemirror/language`
+            // owns the facets that tie a language's syntax tree to the
+            // highlighter; if it is bundled while `lang-json`/`lang-markdown`
+            // stay external, the consumer ends up with two instances of it —
+            // the parser registers its tree against one set of facets and
+            // `syntaxHighlighting()` reads the other, so code renders
+            // completely unhighlighted with no error anywhere.
+            // `@codemirror/commands` is the same hazard for the default keymap.
             external: [
                 'vue',
                 'apexcharts',
                 '@codemirror/state',
                 '@codemirror/view',
+                '@codemirror/language',
+                '@codemirror/commands',
                 '@codemirror/lang-json',
                 '@codemirror/lang-markdown',
             ],