diff --git a/nuxt.config.ts b/nuxt.config.ts
index 508ab3c6..3705788e 100644
--- a/nuxt.config.ts
+++ b/nuxt.config.ts
@@ -1,11 +1,15 @@
 import { existsSync } from 'node:fs'
 import { fileURLToPath } from 'node:url'
 import { unpublishedAgentPaths } from './layers/marketing/app/utils/agent-pages'
+import pkg from './package.json'
 import { dependencyPluginCompat } from './scripts/lib/dependency-plugin-compat'
 import { withBuildAssetMissFallthrough } from './scripts/lib/static-asset-fallthrough'
 import { externalCheckin } from './shared/checkin-external'
+import { iconifyCollections } from './shared/icon-collections'
 import { SENTRY_DSN, sentryRelease, sentryReportingEnabled } from './shared/sentry'
 
+const iconCollections = iconifyCollections(pkg)
+
 const hasSentryAuthToken = Boolean(process.env.SENTRY_AUTH_TOKEN)
   || existsSync('.env.sentry-build-plugin')
 
@@ -608,6 +612,7 @@ export default defineNuxtConfig({
   // inlines just those. The Iconify API fallback is off, so a visitor's browser
   // never calls api.iconify.design. See docs/ops/bundle-baseline-2026-07-23.md.
   icon: {
+    collections: iconCollections,
     serverBundle: false,
     fallbackToApi: false,
     clientBundle: {
diff --git a/shared/icon-collections.ts b/shared/icon-collections.ts
new file mode 100644
index 00000000..e3b9bb4b
--- /dev/null
+++ b/shared/icon-collections.ts
@@ -0,0 +1,26 @@
+/**
+ * The collection names `icon.collections` in nuxt.config.ts must list.
+ *
+ * With `serverBundle: false` and no API fallback, @nuxt/icon registers no
+ * collection names, so it splits `i-vscode-icons-foo` at the first hyphen and
+ * looks up collection `vscode`. The icon never resolves: SSR ships a bare class
+ * and logs a warning. Naming every installed collection fixes the split.
+ *
+ * Only `dependencies` count. An `@iconify-json/*` package that slips into
+ * `devDependencies` silently drops its collection here, which is exactly the
+ * failure above, so every icon package this site renders with must stay a
+ * runtime dependency.
+ */
+
+const ICONIFY_PREFIX = '@iconify-json/'
+
+export interface PackageManifest {
+  dependencies?: Record<string, string>
+  devDependencies?: Record<string, string>
+}
+
+export function iconifyCollections(pkg: PackageManifest): string[] {
+  return Object.keys(pkg.dependencies ?? {})
+    .filter(name => name.startsWith(ICONIFY_PREFIX))
+    .map(name => name.slice(ICONIFY_PREFIX.length))
+}
diff --git a/test/unit/icon-collections.test.ts b/test/unit/icon-collections.test.ts
new file mode 100644
index 00000000..ce453f83
--- /dev/null
+++ b/test/unit/icon-collections.test.ts
@@ -0,0 +1,34 @@
+// @vitest-environment node
+import { describe, expect, it } from 'vitest'
+import { iconifyCollections } from '#shared/icon-collections'
+
+describe('iconifyCollections', () => {
+  it('names every installed collection in dependency order', () => {
+    expect(iconifyCollections({
+      dependencies: {
+        '@iconify-json/vscode-icons': 'catalog:',
+        '@iconify-json/simple-icons': 'catalog:',
+      },
+    })).toEqual(['vscode-icons', 'simple-icons'])
+  })
+
+  it('ignores dependencies that are not icon collections', () => {
+    expect(iconifyCollections({
+      dependencies: {
+        'nuxt': 'catalog:',
+        '@iconify-json/lucide': 'catalog:',
+      },
+    })).toEqual(['lucide'])
+  })
+
+  it('excludes an icon package that only sits in devDependencies', () => {
+    expect(iconifyCollections({
+      dependencies: { '@iconify-json/lucide': 'catalog:' },
+      devDependencies: { '@iconify-json/vscode-icons': 'catalog:' },
+    })).toEqual(['lucide'])
+  })
+
+  it('names nothing when no icon packages are installed', () => {
+    expect(iconifyCollections({ dependencies: { nuxt: 'catalog:' } })).toEqual([])
+  })
+})