diff --git a/Dockerfile b/Dockerfile
index 4dffd06..25a7b20 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -23,7 +23,13 @@ RUN apk add --no-cache curl
 ENV NODE_ENV=production
 
 COPY --from=build /usr/src/app ./
-RUN pnpm install --frozen-lockfile
+RUN pnpm install --frozen-lockfile \
+    # Run as the non-root `node` user (uid 1000, shipped by node:22-alpine).
+    # Ponder writes its cache under the workdir and pnpm reads /pnpm at runtime,
+    # so both must be owned by `node`.
+    && chown -R node:node /usr/src/app /pnpm
+
+USER node
 
 HEALTHCHECK \
     --start-period=24h \
diff --git a/src/application/helpers/orderbookClient.ts b/src/application/helpers/orderbookClient.ts
index a599282..33dc24c 100644
--- a/src/application/helpers/orderbookClient.ts
+++ b/src/application/helpers/orderbookClient.ts
@@ -23,7 +23,16 @@ import { pgSchema, integer, text } from "drizzle-orm/pg-core";
 import { encodeAbiParameters, keccak256, type Hex } from "viem";
 import { type OrderType } from "../../utils/order-types";
 import { COMPOSABLE_COW_HANDLER_ADDRESSES, ORDERBOOK_API_URLS } from "../../data";
-import { BOOTSTRAP_MAX_PAGES, BOOTSTRAP_PAGE_SIZE, ORDERBOOK_HTTP_TIMEOUT_MS, SIGNING_SCHEME_EIP1271 } from "../../constants";
+import {
+  BOOTSTRAP_MAX_PAGES,
+  BOOTSTRAP_PAGE_SIZE,
+  ORDERBOOK_HTTP_TIMEOUT_MS,
+  ORDERBOOK_MAX_RETRIES,
+  ORDERBOOK_RETRY_BASE_MS,
+  ORDERBOOK_RETRY_BUDGET_MS,
+  ORDERBOOK_RETRY_MAX_DELAY_MS,
+  SIGNING_SCHEME_EIP1271,
+} from "../../constants";
 import { decodeEip1271Signature } from "../decoders/erc1271Signature";
 import { fetchWithTimeout, TimeoutError, withTimeout } from "./withTimeout";
 import { log } from "./logger";
@@ -300,6 +309,75 @@ export async function fetchOwnerOrderStatuses(
 
 // ─── API calls ───────────────────────────────────────────────────────────────
 
+/**
+ * The orderbook API refused to answer (HTTP 429 or 5xx) after bounded retries.
+ * Distinct from "the API has no such order" (a UID simply absent from a 2xx
+ * body) so callers / dashboards can alarm on an unavailable API rather than
+ * silently treating it as "order not on API yet".
+ */
+export class OrderbookUnavailableError extends Error {
+  constructor(
+    public readonly status: number,
+    public readonly endpoint: string,
+  ) {
+    super(`[COW:orderbook-unavailable] ${endpoint} responded ${status}`);
+    this.name = "OrderbookUnavailableError";
+  }
+}
+
+const sleep = (ms: number): Promise<void> => new Promise((resolve) => setTimeout(resolve, ms));
+
+/** Parse a `Retry-After` header (delta-seconds or HTTP-date) into milliseconds; null if absent/unparseable. */
+function parseRetryAfter(value: string | null): number | null {
+  if (!value) return null;
+  const seconds = Number(value);
+  if (Number.isFinite(seconds)) return Math.max(0, seconds * 1000);
+  const date = Date.parse(value);
+  if (!Number.isNaN(date)) return Math.max(0, date - Date.now());
+  return null;
+}
+
+/**
+ * `fetchWithTimeout` plus bounded retry/backoff for transient orderbook errors.
+ *
+ * Returns the Response on a 2xx. On 429 it honors `Retry-After` (capped at
+ * ORDERBOOK_RETRY_MAX_DELAY_MS); on 5xx it uses exponential backoff. Retries
+ * stop once ORDERBOOK_MAX_RETRIES is reached or the next sleep would push the
+ * loop past ORDERBOOK_RETRY_BUDGET_MS — at which point it throws
+ * OrderbookUnavailableError instead of holding the block transaction open.
+ * A TimeoutError from the underlying fetch propagates unchanged.
+ */
+async function fetchOrderbook(
+  url: string,
+  init: RequestInit | undefined,
+  endpoint: string,
+): Promise<Response> {
+  let spent = 0;
+  for (let attempt = 0; ; attempt++) {
+    const response = await fetchWithTimeout(url, init, ORDERBOOK_HTTP_TIMEOUT_MS, endpoint);
+    if (response.ok) return response;
+
+    const retryable = response.status === 429 || response.status >= 500;
+    if (!retryable || attempt >= ORDERBOOK_MAX_RETRIES) {
+      throw new OrderbookUnavailableError(response.status, endpoint);
+    }
+
+    const retryAfterMs =
+      response.status === 429 ? parseRetryAfter(response.headers.get("retry-after")) : null;
+    const backoffMs = ORDERBOOK_RETRY_BASE_MS * 2 ** attempt;
+    const delay = Math.min(retryAfterMs ?? backoffMs, ORDERBOOK_RETRY_MAX_DELAY_MS);
+
+    // Fail fast rather than hold the block transaction open past our budget.
+    if (spent + delay > ORDERBOOK_RETRY_BUDGET_MS) {
+      throw new OrderbookUnavailableError(response.status, endpoint);
+    }
+
+    log("warn", "ob:retry", { endpoint, status: response.status, attempt: attempt + 1, delayMs: delay, retryAfterMs });
+    await sleep(delay);
+    spent += delay;
+  }
+}
+
 /** Fetch orders for an owner with pagination. maxPages limits how many pages are fetched (0 = unlimited).
  *  signingScheme, if provided, is appended as a query param — the API filters server-side when supported,
  *  reducing payload for owners with many ECDSA orders mixed with composable ones.
@@ -321,16 +399,7 @@ async function fetchAccountOrders(
     if (signingScheme) params.set("signingScheme", signingScheme);
     const url = `${apiBaseUrl}/api/v1/account/${owner}/orders?${params.toString()}`;
     try {
-      const response = await fetchWithTimeout(
-        url,
-        undefined,
-        ORDERBOOK_HTTP_TIMEOUT_MS,
-        "ob:account",
-      );
-      if (!response.ok) {
-        log("warn", "ob:accountError", { status: response.status, owner });
-        break;
-      }
+      const response = await fetchOrderbook(url, undefined, "ob:account");
       const page = (await response.json()) as OrderbookOrder[];
       allOrders.push(...page);
       pagesFetched++;
@@ -338,6 +407,10 @@ async function fetchAccountOrders(
       if (maxPages > 0 && pagesFetched >= maxPages) break; // page cap reached
       offset += page.length;
     } catch (err) {
+      if (err instanceof OrderbookUnavailableError) {
+        log("error", "ob:unavailable", { endpoint: "ob:account", status: err.status, owner });
+        break;
+      }
       if (err instanceof TimeoutError) {
         log("warn", "ob:accountTimeout", { owner, offset, after: ORDERBOOK_HTTP_TIMEOUT_MS });
         break;
@@ -368,23 +441,22 @@ async function fetchOrdersByUids(
   const chunkResults = await Promise.all(
     chunks.map(async (chunk, idx) => {
       try {
-        const response = await fetchWithTimeout(
+        const response = await fetchOrderbook(
           url,
           {
             method: "POST",
             headers: { "Content-Type": "application/json" },
             body: JSON.stringify(chunk),
           },
-          ORDERBOOK_HTTP_TIMEOUT_MS,
           "ob:byUids",
         );
-        if (!response.ok) {
-          log("warn", "ob:batchFetchError", { status: response.status, uids: chunk.length, offset: idx * BATCH_SIZE });
-          return [] as OrderbookOrder[];
-        }
         const raw = (await response.json()) as { order: OrderbookOrder }[];
         return raw.flatMap((item) => (item?.order != null ? [item.order] : []));
       } catch (err) {
+        if (err instanceof OrderbookUnavailableError) {
+          log("error", "ob:unavailable", { endpoint: "ob:byUids", status: err.status, uids: chunk.length, offset: idx * BATCH_SIZE });
+          return [] as OrderbookOrder[];
+        }
         if (err instanceof TimeoutError) {
           log("warn", "ob:batchFetchTimeout", { uids: chunk.length, offset: idx * BATCH_SIZE, after: ORDERBOOK_HTTP_TIMEOUT_MS });
           return [] as OrderbookOrder[];
diff --git a/src/constants.ts b/src/constants.ts
index ef27867..40c6e61 100644
--- a/src/constants.ts
+++ b/src/constants.ts
@@ -65,6 +65,22 @@ export const DETERMINISTIC_CANCEL_SWEEP_INTERVAL = 100n;
  */
 export const ORDERBOOK_HTTP_TIMEOUT_MS = 10_000;
 
+/**
+ * Bounded retry for transient orderbook failures (HTTP 429 / 5xx).
+ *
+ * These calls run inside Ponder block handlers that hold a DB transaction open,
+ * so the retry loop must stay short — we cannot honor a large `Retry-After` by
+ * sleeping (Postgres would terminate the connection). The loop adds at most
+ * ORDERBOOK_RETRY_BUDGET_MS of wall-clock; if a `Retry-After` (or backoff) would
+ * exceed the budget, we fail fast and let the next poll (~ORDERBOOK_POLL_INTERVAL
+ * blocks later) retry naturally — but the failure is logged as a rate-limit/
+ * server error, not as "order not on API yet".
+ */
+export const ORDERBOOK_MAX_RETRIES = 2; // ≤ 3 attempts total
+export const ORDERBOOK_RETRY_BASE_MS = 250; // exponential backoff base
+export const ORDERBOOK_RETRY_MAX_DELAY_MS = 2_000; // cap on a single sleep (incl. Retry-After)
+export const ORDERBOOK_RETRY_BUDGET_MS = 4_000; // total wall-clock the retry loop may add
+
 /**
  * Hard wall-clock cap for a block handler's aggregate `context.client.multicall`
  * call (OrderDiscoveryPoller, CancellationWatcher). viem has no per-call signal; the timer races the promise and
diff --git a/tests/helpers/orderbookClient.test.ts b/tests/helpers/orderbookClient.test.ts
index b1afc95..6454ad6 100644
--- a/tests/helpers/orderbookClient.test.ts
+++ b/tests/helpers/orderbookClient.test.ts
@@ -17,6 +17,7 @@ vi.mock("ponder", () => ({
 }));
 
 import * as data from "../../src/data";
+import { ORDERBOOK_MAX_RETRIES } from "../../src/constants";
 import { fetchOrderStatusByUids, fetchOwnerOrderStatuses } from "../../src/application/helpers/orderbookClient";
 
 // ─── Helpers ─────────────────────────────────────────────────────────────────
@@ -211,6 +212,81 @@ describe("fetchOrderStatusByUids", () => {
   });
 });
 
+// ─── Resilience: 429 / 5xx handling ───────────────────────────────────────────
+
+/** Capture structured `log()` output — the logger writes warn/error as JSON via console.error. */
+function captureErrorLogs() {
+  const lines: Record<string, unknown>[] = [];
+  const spy = vi.spyOn(console, "error").mockImplementation((line: unknown) => {
+    try {
+      lines.push(JSON.parse(String(line)));
+    } catch {
+      /* non-JSON line — ignore */
+    }
+  });
+  return {
+    has: (msg: string) => lines.some((l) => l.msg === msg),
+    find: (msg: string) => lines.find((l) => l.msg === msg),
+    restore: () => spy.mockRestore(),
+  };
+}
+
+describe("orderbook resilience (429 / 5xx)", () => {
+  beforeAll(() => {
+    data.ORDERBOOK_API_URLS[TEST_CHAIN_ID] = "http://placeholder";
+  });
+
+  afterAll(() => {
+    delete (data.ORDERBOOK_API_URLS as Record<number, string | undefined>)[TEST_CHAIN_ID];
+  });
+
+  it("retries a 429 (honoring Retry-After) and succeeds on a later attempt", async () => {
+    let calls = 0;
+    const { url, close } = await startServer((_req, res) => {
+      calls++;
+      if (calls === 1) {
+        res.writeHead(429, { "retry-after": "0", "content-type": "application/json" });
+        res.end(JSON.stringify({ message: "rate limited" }));
+        return;
+      }
+      res.writeHead(200, { "content-type": "application/json" });
+      res.end(JSON.stringify([makeWrappedOrder(UID_A, "fulfilled")]));
+    });
+    data.ORDERBOOK_API_URLS[TEST_CHAIN_ID] = url;
+    const logs = captureErrorLogs();
+    try {
+      const result = await fetchOrderStatusByUids(makeContext(), TEST_CHAIN_ID, [UID_A]);
+      expect(calls).toBe(2);
+      expect(result.get(UID_A)?.status).toBe("fulfilled");
+      expect(logs.has("ob:unavailable")).toBe(false);
+    } finally {
+      logs.restore();
+      await close();
+    }
+  });
+
+  it("classifies a persistent 429 as ob:unavailable and stops after bounded retries", async () => {
+    let calls = 0;
+    const { url, close } = await startServer((_req, res) => {
+      calls++;
+      res.writeHead(429, { "retry-after": "0", "content-type": "application/json" });
+      res.end(JSON.stringify({ message: "rate limited" }));
+    });
+    data.ORDERBOOK_API_URLS[TEST_CHAIN_ID] = url;
+    const logs = captureErrorLogs();
+    try {
+      const result = await fetchOrderStatusByUids(makeContext(), TEST_CHAIN_ID, [UID_A]);
+      expect(calls).toBe(ORDERBOOK_MAX_RETRIES + 1); // bounded: 1 initial + retries
+      expect(result.has(UID_A)).toBe(false); // absent from map…
+      expect(logs.find("ob:unavailable")?.status).toBe(429); // …but the cause is logged distinctly
+    } finally {
+      logs.restore();
+      await close();
+    }
+  });
+
+});
+
 // ─── fetchOwnerOrderStatuses tests ────────────────────────────────────────────
 
 const FAKE_OWNER = "0xaabbccddEEff0011223344556677889900aabbcc" as Hex;