diff --git a/tests/e2e/playwright.config.ts b/tests/e2e/playwright.config.ts
index 986b2e8..e0e1f3e 100644
--- a/tests/e2e/playwright.config.ts
+++ b/tests/e2e/playwright.config.ts
@@ -42,7 +42,10 @@ export default defineConfig({
     },
     {
       name: "admin",
-      testMatch: /11-.*\.spec\.ts/,
+      // 23- joins 2026-11-02 (Audiobookshelf SSO): it needs BOTH halves of the admin
+      // fixture — a live authentik session to ride the OIDC round trip, and the
+      // qa-e2e-admin group membership that grants site admin in the app.
+      testMatch: /(11|23)-.*\.spec\.ts/,
       use: { storageState: ".auth/qa-e2e-admin.json" },
       dependencies: ["setup"],
     },
diff --git a/tests/e2e/specs/23-audiobookshelf-sso.spec.ts b/tests/e2e/specs/23-audiobookshelf-sso.spec.ts
new file mode 100644
index 0000000..9dc341c
--- /dev/null
+++ b/tests/e2e/specs/23-audiobookshelf-sso.spec.ts
@@ -0,0 +1,92 @@
+import { expect, test } from "@playwright/test";
+
+// Audiobookshelf: the SSO round trip must land a session with a real permission level.
+//
+// The service answers on a LAN address with no DNS name and no Caddy vhost, so it is in no
+// guarded-vhost list and no other spec ever fetched a byte of it — every deploy gate passed
+// while its login was dead. Two defect classes, both caught live on 2026-11-02:
+//
+//  1. The bundle must be BUILT for /audiobookshelf (ROUTER_BASE_PATH in the quadlet). Built
+//     for "/" the container still answers /healthcheck and still serves index.html, so the
+//     deploy health gate is green while the browser sees a blank page: every <script>
+//     resolves against the root, misses the static allowlist, and falls through to the SPA
+//     catch-all that returns index.html as text/html. Hence the MIME assertion below — the
+//     one thing that distinguishes a booted SPA from a served HTML stub.
+//  2. The authentik provider row must carry grant_types AND the built-in OpenID scope
+//     mappings (provisioned by scripts/authentik-audiobookshelf-sso.sh). A blueprint
+//     re-import reverts hand-made provider rows silently, and the wire errors are generic:
+//     oauthlib's "The request is otherwise malformed" for an empty grant list, then
+//     "insufficient_scope" from ABS's /userinfo call for a short scope. Only the level
+//     assertion below — that the abs_groups claim granted site admin — sees either.
+const HOST = "192.168.0.235:8000";
+const ABS = `http://${HOST}/audiobookshelf`;
+
+test("SSO round trip boots the SPA and grants a real Audiobookshelf session", async ({
+  page,
+}) => {
+  test.setTimeout(180_000);
+
+  const scripts: { url: string; type: string }[] = [];
+  page.on("response", (res) => {
+    const u = new URL(res.url());
+    if (u.host === HOST && u.pathname.endsWith(".js")) {
+      scripts.push({ url: u.pathname, type: res.headers()["content-type"] ?? "" });
+    }
+  });
+
+  await page.goto(`${ABS}/login`, { waitUntil: "domcontentloaded" });
+  const sso = page.getByText("Sign in with Authentik");
+  await expect(sso).toBeVisible();
+  await sso.click();
+
+  // The admin project's storageState carries a live authentik session, so this is a silent
+  // round trip: authorize -> code -> callback -> token. Still on /login means the IdP
+  // refused the authorize request or ABS rejected the code exchange.
+  await expect
+    .poll(() => !new URL(page.url()).pathname.endsWith("/login"), { timeout: 90_000 })
+    .toBe(true);
+
+  await expect
+    .poll(
+      async () => {
+        const u = new URL(page.url());
+        return u.host === HOST && u.pathname.startsWith("/audiobookshelf");
+      },
+      { timeout: 30_000 },
+    )
+    .toBe(true);
+
+  // Defect 1 gate: nothing the app loaded may be HTML dressed as a script. The render proof
+  // is the SSO button above — it only exists once the bundle has executed, so no DOM-shape
+  // guess is needed (the shell's own mount markup says nothing about whether it booted).
+  expect(scripts.length, "the SPA loaded no JavaScript").toBeGreaterThan(2);
+  for (const s of scripts) {
+    expect(s.type, `${s.url} arrived as ${s.type}`).toContain("javascript");
+  }
+
+  // The token the app landed on is the credential its own API must accept. Give the SPA a
+  // moment to finish the exchange: the URL leaves /login the instant authentik bounces back
+  // through the callback route, which is BEFORE the app has stored what it exchanged.
+  const grabToken = () =>
+    page.evaluate(() => {
+      for (let i = 0; i < localStorage.length; i++) {
+        const v = localStorage.getItem(localStorage.key(i) as string) || "";
+        if (/^[A-Za-z0-9_-]+\.[A-Za-z0-9_-]+\.[A-Za-z0-9_-]+$/.test(v)) return v;
+      }
+      const c = document.cookie.match(/(?:^|;\s*)abs_token=([^;]+)/);
+      return c ? decodeURIComponent(c[1]) : "";
+    });
+  await expect.poll(grabToken, { timeout: 60_000 }).not.toBe("");
+  const token = await grabToken();
+
+  const me = await page.request.get(`${ABS}/api/me`, {
+    headers: { Authorization: `Bearer ${token}` },
+  });
+  expect(me.status()).toBe(200);
+  const user = await me.json();
+  expect(user.username).toBe("qa-e2e-admin");
+  // Site role, derived ONLY from the abs_groups claim: it says "admin" if and only if the
+  // scope mapping reached ABS with audiobookshelf_admins in the list. A short token scope
+  // (missing OpenID mappings) never gets this far — the exchange dies before it.
+  expect(user.type).toBe("admin");
+});