diff --git a/composer.json b/composer.json
index 4a02727..c153c37 100644
--- a/composer.json
+++ b/composer.json
@@ -29,7 +29,7 @@
         "milpa/tool-runtime": ">=0.13 <1.0",
         "nyholm/psr7": "^1.8",
         "nyholm/psr7-server": "^1.1",
-        "milpa/live-web": ">=0.26.1 <1.0"
+        "milpa/live-web": ">=0.27 <1.0"
     },
     "conflict": {
         "milpa/agent": "<0.5",
diff --git a/src/Plugins/HelloPlugin/Controllers/HomeController.php b/src/Plugins/HelloPlugin/Controllers/HomeController.php
index becff47..57264a0 100644
--- a/src/Plugins/HelloPlugin/Controllers/HomeController.php
+++ b/src/Plugins/HelloPlugin/Controllers/HomeController.php
@@ -20,8 +20,10 @@
 use Milpa\Live\Components\CodeBlockComponent;
 use Milpa\Live\Contracts\Component\ComponentDefinitionInterface;
 use Milpa\Live\Contracts\Rendering\ComponentRendererInterface;
+use App\Plugins\HelloPlugin\HelloPlugin;
 use Milpa\Live\Rendering\BrandMarkHtmlRenderer;
 use Milpa\Live\Rendering\CodeBlockHtmlRenderer;
+use Milpa\Live\Support\DesignTokens;
 use Milpa\Live\ValueObjects\ComponentContext;
 use Milpa\Live\ValueObjects\RenderRequest;
 use Milpa\Live\ValueObjects\RenderTarget;
@@ -223,12 +225,30 @@ private function elsewhere(): string
         return $html;
     }
 
+    /**
+     * The design system's tags, from the authority rather than from typing.
+     *
+     * The three filenames used to be spelled here, a fourth time in this family, and the prefix a
+     * fourth WAY — which is how `/design/` came to exist next to `/webauthn/`, `/admin/assets/` and
+     * `/live/` without anyone choosing four. {@see HelloPlugin::designPrefix()} owns the prefix and
+     * {@see DesignTokens::urls()} owns the filenames; this method owns neither
+     * (greenhouse decisions/0308).
+     */
+    private static function designLinks(): string
+    {
+        $design = DesignTokens::urls(HelloPlugin::designPrefix());
+
+        return '<link rel="stylesheet" href="' . $design[DesignTokens::TOKENS] . '">'
+            . '<link rel="stylesheet" href="' . $design[DesignTokens::FONTS] . '">'
+            . DesignTokens::iconLink($design[DesignTokens::APP_ICON]);
+    }
+
     private function html(): string
     {
         $assets = self::assets();
 
         return \str_replace(
-            ['__GREETING__', '__MARK__', '__DOOR__', '__WAYS_OUT__', '__ELSEWHERE__', '__STYLES__', '__SCRIPTS__'],
+            ['__GREETING__', '__MARK__', '__DOOR__', '__WAYS_OUT__', '__ELSEWHERE__', '__DESIGN__', '__STYLES__', '__SCRIPTS__'],
             [
                 htmlspecialchars($this->greeting, \ENT_QUOTES, 'UTF-8'),
                 // READY, not `sown`: the mark reports what the surface is doing, and this page has
@@ -238,6 +258,7 @@ private function html(): string
                 self::door(),
                 self::waysOut(),
                 $this->elsewhere(),
+                self::designLinks(),
                 $assets->styleTag(),
                 $assets->scriptTag(),
             ],
@@ -248,9 +269,7 @@ private function html(): string
                     <meta charset="utf-8">
                     <title>Milpa is running</title>
                     <meta name="viewport" content="width=device-width, initial-scale=1">
-                    <link rel="stylesheet" href="/design/milpa-tokens.css">
-                    <link rel="stylesheet" href="/design/milpa-fonts.css">
-                    <link rel="icon" type="image/svg+xml" href="/design/milpa-app-icon.svg">
+                    __DESIGN__
                     __STYLES__
                     <style>
                         /* LAYOUT AND WORDS ONLY — no colour of its own, and nothing that a component owns.
diff --git a/src/Plugins/HelloPlugin/HelloPlugin.php b/src/Plugins/HelloPlugin/HelloPlugin.php
index 267569b..8808c12 100644
--- a/src/Plugins/HelloPlugin/HelloPlugin.php
+++ b/src/Plugins/HelloPlugin/HelloPlugin.php
@@ -97,6 +97,9 @@ public function uninstall(): void
     {
     }
 
+    /** This house's design-system mount point — see {@see designPrefix()}. */
+    private const string DESIGN_PREFIX = '/design';
+
     public function enable(): void
     {
     }
@@ -105,6 +108,19 @@ public function disable(): void
     {
     }
 
+    /**
+     * Where this house mounts the design system — the one place the prefix is typed.
+     *
+     * The five files under it come from {@see \Milpa\Live\Support\DesignTokens::urls()} rather than from typing, and the
+     * two route PATTERNS below (`{file}`, `{face}`) are this house's shape, which no authority can
+     * produce for it. What is shared is the prefix and the filenames; the shape stays local
+     * (greenhouse decisions/0308).
+     */
+    public static function designPrefix(): string
+    {
+        return self::DESIGN_PREFIX;
+    }
+
     /** @return list<Route> */
     public function routes(): array
     {
@@ -120,13 +136,13 @@ public function routes(): array
             // and two of them were unreadable. A page that can link the tokens never has to invent a
             // colour — see {@see DesignController} (greenhouse decisions/0298).
             new Route(
-                path: '/design/{file}',
+                path: self::DESIGN_PREFIX . '/{file}',
                 methods: HttpMethod::GET,
                 name: 'design.file',
                 handler: new HandlerReference(DesignController::class, 'file'),
             ),
             new Route(
-                path: '/design/fonts/{face}',
+                path: self::DESIGN_PREFIX . '/fonts/{face}',
                 methods: HttpMethod::GET,
                 name: 'design.face',
                 handler: new HandlerReference(DesignController::class, 'face'),
diff --git a/tests/Console/ApplicationTest.php b/tests/Console/ApplicationTest.php
index dc1960f..f0c3bcc 100644
--- a/tests/Console/ApplicationTest.php
+++ b/tests/Console/ApplicationTest.php
@@ -464,6 +464,14 @@ public function testRepairWithoutAPackageSaysHowItIsUsed(): void
         $texto = (string) ob_get_clean();
 
         self::assertSame(1, $codigo);
-        self::assertStringContainsString('uso: coa repair', $texto);
+        // 🚨 THE SHAPE, NOT THE SENTENCE. This asserted `uso: coa repair` — a dependency's exact copy,
+        // in the language it happened to be written in. `milpa/app-runtime` translated that line and
+        // CI went red here while this suite stayed green locally, because the lock pinned v0.151.0 and
+        // CI's `composer require --dev` re-resolved to v0.151.4. A package behind the registry does
+        // not break the run; it makes the suite lie (greenhouse decisions/0308).
+        //
+        // What this test actually cares about is that a bare `repair` REFUSES and names the argument
+        // it wanted. The wording is app-runtime's to choose and to internationalize.
+        self::assertStringContainsString('repair <', $texto, 'it names the argument it was missing');
     }
 }
diff --git a/tests/Plugins/TheHouseDerivesItsDesignUrlsTest.php b/tests/Plugins/TheHouseDerivesItsDesignUrlsTest.php
new file mode 100644
index 0000000..fafab1d
--- /dev/null
+++ b/tests/Plugins/TheHouseDerivesItsDesignUrlsTest.php
@@ -0,0 +1,123 @@
+<?php
+
+/**
+ * This file is part of milpa/framework.
+ *
+ * (c) Rodrigo Vicente - TeamX Agency — https://teamx.agency <hola@teamx.agency>
+ *
+ * @license Apache-2.0
+ *
+ * @link    https://github.com/getmilpa/framework
+ */
+
+declare(strict_types=1);
+
+namespace App\Tests\Plugins;
+
+use App\Plugins\HelloPlugin\HelloPlugin;
+use Milpa\Container\DIContainer;
+use Milpa\Live\Support\DesignTokens;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * 🚨 THIS HOUSE DERIVES ITS DESIGN-SYSTEM URLS; IT TYPES THE PREFIX ONCE AND NOTHING ELSE.
+ *
+ * `decisions/0243` stopped the tokens being COPIED — three packages carried identical copies that had
+ * drifted, all three missing `--space-32`, and now the file ships in `milpa/live-web`. What it did not
+ * stop was the TYPING, and this house is the proof of the cost: `/design/` was invented here in the
+ * same afternoon that `/webauthn/`, `/admin/assets/` and `/live/` already existed, by someone who
+ * could not see the other three from where they were writing (greenhouse decisions/0308).
+ *
+ * A prefix per host is not the defect — it is a decision written where it is made
+ * ({@see DesignTokens::iconLink()}: «each serves this file from its own asset route, with its own
+ * cache policy»), because a plugin whose pages work the moment it is installed cannot depend on
+ * another plugin's routes being mounted. Four prefixes nobody chose is the defect.
+ */
+#[CoversClass(HelloPlugin::class)]
+final class TheHouseDerivesItsDesignUrlsTest extends TestCase
+{
+    /**
+     * 🚨 NO STRING IN `src/` SPELLS A DESIGN-SYSTEM FILENAME OR REPEATS THE PREFIX.
+     *
+     * A guard, not an example. The three `<link>`s that used to live in the page's `<head>` were the
+     * fourth copy of those filenames in this family, and the page could not have known: nothing it
+     * imported mentioned the other three. What a test can see, a reader cannot.
+     */
+    public function testNoStringInTheSourceSpellsADesignUrl(): void
+    {
+        $offenders = [];
+
+        foreach (self::phpFiles(\dirname(__DIR__, 2) . '/src') as $file) {
+            foreach (explode("\n", (string) file_get_contents($file)) as $n => $line) {
+                $trimmed = ltrim($line);
+                // Comments and docblocks name these URLs to explain them; that is prose, not a link.
+                if ($trimmed === '' || str_starts_with($trimmed, '*') || str_starts_with($trimmed, '//') || str_starts_with($trimmed, '/*')) {
+                    continue;
+                }
+                // The one exemption: something has to say where this house mounts them, and it says it once.
+                if (str_contains($line, 'DESIGN_PREFIX = ')) {
+                    continue;
+                }
+                $spellsAFile = preg_match('#[\'"][^\'"]*milpa-(tokens|fonts|wordmark|wordmark-light|app-icon)\.(css|svg)#', $line) === 1;
+                $repeatsThePrefix = preg_match("#['\"]/design#", $line) === 1;
+                if ($spellsAFile || $repeatsThePrefix) {
+                    $offenders[] = basename($file) . ':' . ($n + 1) . '  ' . trim($line);
+                }
+            }
+        }
+
+        self::assertSame([], $offenders, "derive these from DesignTokens::urls(HelloPlugin::designPrefix()) instead:\n" . implode("\n", $offenders));
+    }
+
+    /**
+     * The routes this house declares for the system sit under the prefix it declares.
+     *
+     * The route PATTERNS (`{file}`, `{face}`) are this house's own shape and no authority can produce
+     * them for it — one catch-all here, five named routes in the passkey door, and both are right for
+     * their host. What moved is the prefix and the filenames; the shape stayed local.
+     */
+    public function testTheDesignRoutesSitUnderTheDeclaredPrefix(): void
+    {
+        $paths = [];
+        foreach ((new HelloPlugin(new DIContainer()))->routes() as $route) {
+            if (str_contains($route->path, 'design') || str_contains($route->path, 'fonts')) {
+                $paths[] = $route->path;
+            }
+        }
+
+        self::assertSame([
+            HelloPlugin::designPrefix() . '/{file}',
+            HelloPlugin::designPrefix() . '/fonts/{face}',
+        ], $paths);
+
+        // And the URLs the page links resolve INTO those patterns — the stylesheet's own relative
+        // `url('fonts/…')` is why the second one exists at all.
+        $urls = DesignTokens::urls(HelloPlugin::designPrefix());
+        self::assertSame(HelloPlugin::designPrefix() . '/' . DesignTokens::TOKENS, $urls[DesignTokens::TOKENS]);
+
+        $faces = array_diff_key($urls, array_flip([
+            DesignTokens::TOKENS, DesignTokens::FONTS,
+            DesignTokens::WORDMARK, DesignTokens::WORDMARK_LIGHT, DesignTokens::APP_ICON,
+        ]));
+        self::assertNotSame([], $faces, 'a stylesheet whose faces are not served renders as missing type, not as an error');
+        foreach ($faces as $url) {
+            self::assertStringStartsWith(HelloPlugin::designPrefix() . '/fonts/', $url);
+        }
+    }
+
+    /**
+     * @return list<string>
+     */
+    private static function phpFiles(string $root): array
+    {
+        $found = [];
+        foreach (new \RecursiveIteratorIterator(new \RecursiveDirectoryIterator($root)) as $file) {
+            if ($file instanceof \SplFileInfo && $file->getExtension() === 'php') {
+                $found[] = $file->getPathname();
+            }
+        }
+
+        return $found;
+    }
+}