diff --git a/runtime/deploy.sh b/runtime/deploy.sh
index f906218..85f4c96 100755
--- a/runtime/deploy.sh
+++ b/runtime/deploy.sh
@@ -25,5 +25,8 @@ for ENVF in /srv/cayce-core/.env /srv/cayce-nostr/.env /home/ubuntu/cayce-social
   grep -q "^IDENTITY_PATH=" "$ENVF" 2>/dev/null || echo "IDENTITY_PATH=/home/ubuntu/cayce-ops/prompts/cayce-identity.md" >> "$ENVF"
 done
 
+sudo install -m 644 '$SRC/hardcap/admin.ts' /srv/hardcap-backend/src/routes/admin.ts 2>/dev/null || true
+install -m 755 '$SRC/hardcap/test-admin-auth.mjs' /srv/hardcap-backend/runtime-tests/test-admin-auth.mjs 2>/dev/null || true
+sudo systemctl restart hardcap-backend
 sudo systemctl restart cayce-nostr
 echo "deploy OK — mode=$(grep -h "^CAYCE_PUBLISH_MODE=" /srv/cayce-core/.env | head -1)"
diff --git a/runtime/hardcap/admin.ts b/runtime/hardcap/admin.ts
index f998953..e8758ca 100644
--- a/runtime/hardcap/admin.ts
+++ b/runtime/hardcap/admin.ts
@@ -4,6 +4,29 @@ import { ingestAllSources } from '../services/ingestion'
 
 const router = Router()
 
+// ── auth middleware (2026-10-31): token obligatorio, comparación en tiempo constante.
+// Fail-closed: sin HARDCAP_ADMIN_TOKEN configurado, TODAS las rutas admin responden 503.
+import { createHash, timingSafeEqual } from 'crypto'
+
+const ADMIN_TOKEN = process.env.HARDCAP_ADMIN_TOKEN || ''
+function _safeEqual(a: string, b: string): boolean {
+  // hash de ambos a longitud fija: sin leak de longitud ni de timing por contenido
+  return timingSafeEqual(createHash('sha256').update(String(a)).digest(), createHash('sha256').update(String(b)).digest())
+}
+function adminAuth(req: any, res: any, next: any) {
+  if (!ADMIN_TOKEN) {
+    console.error('[admin-auth] HARDCAP_ADMIN_TOKEN not set — admin request REFUSED (fail-closed)')
+    return res.status(503).json({ error: 'admin disabled: token not configured' })
+  }
+  const provided = String(req.headers['authorization'] || '').replace(/^Bearer\s+/i, '') || String(req.headers['x-admin-token'] || '')
+  if (provided && _safeEqual(provided, ADMIN_TOKEN)) return next()
+  console.error(`[admin-auth] 401 ${req.method} ${req.originalUrl} from ${req.socket.remoteAddress}`)
+  return res.status(401).json({ error: 'unauthorized' })
+}
+router.use(adminAuth)
+// regla permanente de secretos: jamás loguear el token ni volcar headers.
+
+
 // ── Articles ──────────────────────────────────────────────
 
 // GET /admin/articles?status=QUEUED&topic=lightning
diff --git a/runtime/hardcap/test-admin-auth.mjs b/runtime/hardcap/test-admin-auth.mjs
new file mode 100644
index 0000000..3697e51
--- /dev/null
+++ b/runtime/hardcap/test-admin-auth.mjs
@@ -0,0 +1,31 @@
+// test-admin-auth — verifica el middleware de /admin (hardcap-backend).
+// Ejecutar en la VPS: node /srv/hardcap-backend/runtime-tests/test-admin-auth.mjs
+//   (o node runtime/hardcap/test-admin-auth.mjs desde el repo)
+// Requiere HARDCAP_ADMIN_TOKEN en el .env del servicio y el servicio activo en 127.0.0.1:3001.
+import { readFileSync } from 'node:fs'
+
+const BASE = 'http://127.0.0.1:3001'
+const env = Object.fromEntries(
+  readFileSync('/srv/hardcap-backend/.env', 'utf8').split('\n').filter(l => l.includes('=')).map(l => [l.slice(0, l.indexOf('=')), l.slice(l.indexOf('=') + 1)])
+)
+const TOKEN = env.HARDCAP_ADMIN_TOKEN
+if (!TOKEN) { console.error('HARDCAP_ADMIN_TOKEN no configurado — el test no puede pasar'); process.exit(2) }
+
+let failed = 0
+async function check(name, path, opts, expected) {
+  const r = await fetch(BASE + path, { ...opts, signal: AbortSignal.timeout(8000) })
+  const ok = r.status === expected
+  if (!ok) failed++
+  console.log(`${ok ? '✓' : '✗'} ${name}: esperado ${expected}, obtenido ${r.status}`)
+}
+
+await check('sin token → 401', '/admin/articles?status=QUEUED', {}, 401)
+await check('token incorrecto → 401', '/admin/articles?status=QUEUED', { headers: { Authorization: 'Bearer ' + 'x'.repeat(64) } }, 401)
+await check('token vacío en header → 401', '/admin/sources', { headers: { Authorization: 'Bearer ' } }, 401)
+await check('token correcto → 200', '/admin/articles?status=QUEUED', { headers: { Authorization: `Bearer ${TOKEN}` } }, 200)
+await check('header alternativo X-Admin-Token → 200', '/admin/sources', { headers: { 'x-admin-token': TOKEN } }, 200)
+// la comparación debe ser en tiempo constante: un token de la misma longitud pero distinto NO pasa
+await check('token misma longitud, distinto → 401', '/admin/articles?status=QUEUED', { headers: { Authorization: 'Bearer ' + 'y'.repeat(TOKEN.length) } }, 401)
+
+console.log(failed ? `\n${failed} TESTS FALLARON` : '\nTODOS LOS TESTS PASARON')
+process.exit(failed ? 1 : 0)