diff --git a/lib/exporter/extras.ts b/lib/exporter/extras.ts
new file mode 100644
index 0000000..84cd4dd
--- /dev/null
+++ b/lib/exporter/extras.ts
@@ -0,0 +1,64 @@
+import type { Page } from '@/lib/schema/page'
+
+export type ExtrasOverrides = {
+  robotsText?: string
+  manifest?: Partial<{
+    name: string
+    short_name: string
+    start_url: string
+    display: string
+    theme_color: string
+  }>
+}
+
+function toBytes(s: string): Uint8Array {
+  return new TextEncoder().encode(s)
+}
+
+function buildRobots(base?: string): string {
+  if (base && base.trim().length > 0) return base
+  return 'User-agent: *\n'
+}
+
+function deriveManifest(page: Page) {
+  const name = page.title || 'Landing'
+  const short_name = name.length > 12 ? name.slice(0, 12) : name
+  const start_url = '/'
+  const display = 'standalone'
+  const theme_color = page.theme?.primaryColor || '#0ea5e9'
+  return { name, short_name, start_url, display, theme_color }
+}
+
+export function buildExtrasForPage(page: Page, overrides?: ExtrasOverrides): Record<string, Uint8Array> {
+  const out: Record<string, Uint8Array> = {}
+
+  // robots.txt
+  const robotsText = buildRobots(overrides?.robotsText)
+  out['robots.txt'] = toBytes(robotsText)
+
+  // site.webmanifest
+  const manifestBase = deriveManifest(page)
+  const manifestMerged = { ...manifestBase, ...(overrides?.manifest || {}) }
+  const manifestJson = JSON.stringify(manifestMerged, null, 2)
+  out['site.webmanifest'] = toBytes(manifestJson)
+
+  // Google Sheets 템플릿: actionUrl 미지정 시 포함
+  const action = page.form?.actionUrl?.trim()
+  const hasAction = !!(action && action.length > 0)
+  if (!hasAction) {
+    const code = `/**
+ * Google Apps Script Web App for form submissions
+ * - Deploy as Web App and set URL as form action if needed.
+ */
+function doPost(e){
+  // TODO: handle submission to Google Sheets
+  return ContentService.createTextOutput('OK')
+}
+`
+    const readme = `Google Sheets Apps Script Template\n\n1) Apps Script에서 새 프로젝트를 만들고 아래 Code.gs를 붙여넣으세요.\n2) 배포 > 웹 앱으로 배포 후 URL을 복사해 사용하세요.`
+    out['sheets/Code.gs'] = toBytes(code)
+    out['sheets/README.txt'] = toBytes(readme)
+  }
+
+  return out
+}
diff --git a/lib/exporter/manifest.robots.auto.test.ts b/lib/exporter/manifest.robots.auto.test.ts
new file mode 100644
index 0000000..17b21e7
--- /dev/null
+++ b/lib/exporter/manifest.robots.auto.test.ts
@@ -0,0 +1,32 @@
+import { describe, it, expect } from 'vitest'
+import { pageSchema, type Page } from '@/lib/schema/page'
+import { buildExtrasForPage } from '@/lib/exporter/extras'
+
+function makePage(): Page {
+  return pageSchema.parse({
+    title: 'Auto Extras',
+    locale: 'en',
+    theme: { primaryColor: '#2563eb', fontFamily: 'Inter' },
+    sections: [ { type: 'hero', props: { heading: 'Hello', subheading: 'World', imageUrl: 'https://img/h.png' } } ],
+    form: { actionUrl: '', fields: [], spamProtection: { honeypotFieldName: '_hp', minSubmitSeconds: 2 } },
+    seo: { title: 't', description: 'd' },
+  })
+}
+
+describe('extras 자동 생성', () => {
+  it('robots.txt와 site.webmanifest가 extras에 포함된다', () => {
+    const page = makePage()
+    const extras = buildExtrasForPage(page)
+    const keys = Object.keys(extras)
+    expect(keys).toContain('robots.txt')
+    expect(keys).toContain('site.webmanifest')
+
+    const robots = Buffer.from(extras['robots.txt']).toString('utf8')
+    expect(robots).toContain('User-agent: *')
+
+    const manifestStr = Buffer.from(extras['site.webmanifest']).toString('utf8')
+    const manifest = JSON.parse(manifestStr)
+    expect(manifest.start_url).toBeDefined()
+    expect(manifest.display).toBeDefined()
+  })
+})