diff --git a/.github/scripts/release.mjs b/.github/scripts/release.mjs
index 96b28ab..a07b907 100644
--- a/.github/scripts/release.mjs
+++ b/.github/scripts/release.mjs
@@ -64,6 +64,38 @@ export function validatePackage(pkg, version) {
   assert.equal(pkg.version, version, 'tarball version disagrees with release');
 }
 
+// A successful lookup means the release is visible; Go still verifies the signed checksums in CI.
+// Only the exact missing-tag response is a propagation delay. Inspect both modules so an unrelated
+// failure cannot be mistaken for a delay in the other module.
+export async function goReleaseReady(version, fetcher = fetch) {
+  releaseTags(version);
+  const states = await Promise.all(['gateway', 'gateway/kube'].map(async path => {
+    const module = `github.com/ConfigButler/krm-stream/${path}`;
+    const response = await fetcher(`https://sum.golang.org/lookup/github.com/!config!butler/krm-stream/${path}@v${version}`, {
+      signal: AbortSignal.timeout(30_000),
+    });
+    const body = (await response.text()).trim();
+    if (response.ok) return true;
+    const missing = `not found: ${module}@v${version}: invalid version: unknown revision ${path}/v${version}`;
+    assert.ok((response.status === 404 || response.status === 410) && body === missing,
+      `Go checksum lookup for ${module}@v${version} failed: HTTP ${response.status}: ${body}`);
+    return false;
+  }));
+  return states.every(Boolean);
+}
+
+export async function waitForGoRelease(version, { fetcher = fetch,
+  wait = ms => new Promise(resolve => setTimeout(resolve, ms)), now = Date.now } = {}) {
+  const deadline = now() + 30 * 60_000;
+  while (!await goReleaseReady(version, fetcher)) {
+    const remaining = deadline - now();
+    assert.ok(remaining > 0, `Go checksum records for v${version} are still missing after 30 minutes`);
+    console.log(`Waiting for Go checksum records for v${version}; checking again in ${Math.min(60_000, remaining) / 1_000} seconds.`);
+    await wait(Math.min(60_000, remaining));
+  }
+  console.log(`Go checksum records for v${version} are ready.`);
+}
+
 // A registry read may lag a successful upload. Only recover npm's explicit immutable-version
 // rejection, and only when the registry confirms exactly the validated artifact's bytes.
 export async function publishWithRecovery({ version, integrity, publish, fetcher = fetch,
@@ -94,6 +126,13 @@ const git = (...args) => execFileSync('git', args, { encoding: 'utf8' }).trim();
 const output = (key, value) => appendFileSync(process.env.GITHUB_OUTPUT, `${key}=${value}\n`);
 
 async function main() {
+  // Readiness uses the version already resolved and validated by release preparation.
+  // Require it explicitly so local manifest contents cannot flow into an outbound request.
+  if (process.argv[2] === 'go-ready') {
+    assert.ok(process.env.VERSION, 'go-ready requires an explicit VERSION from release preparation');
+    await waitForGoRelease(process.env.VERSION);
+    return;
+  }
   const version = process.env.VERSION || JSON.parse(readFileSync('.release-please-manifest.json'))['packages/krm-stream'];
   const tags = releaseTags(version);
   if (process.argv[2] === 'resolve') {
@@ -139,7 +178,7 @@ async function main() {
     } });
     console.log(`${packageName}@${version}: ${result}.`);
   } else {
-    throw new Error('usage: release.mjs resolve|verify|publish');
+    throw new Error('usage: release.mjs resolve|go-ready|verify|publish');
   }
 }
 
diff --git a/.github/scripts/release.test.mjs b/.github/scripts/release.test.mjs
index f1e9c9e..ac48d01 100644
--- a/.github/scripts/release.test.mjs
+++ b/.github/scripts/release.test.mjs
@@ -1,6 +1,9 @@
 import assert from 'node:assert/strict';
+import { spawnSync } from 'node:child_process';
+import { tmpdir } from 'node:os';
 import { test } from 'node:test';
-import { needsPublish, packageName, publishWithRecovery, registryMetadata, releaseTags, validatePackage, validateRelease } from './release.mjs';
+import { fileURLToPath } from 'node:url';
+import { goReleaseReady, needsPublish, packageName, publishWithRecovery, registryMetadata, releaseTags, validatePackage, validateRelease, waitForGoRelease } from './release.mjs';
 
 const sha = 'a'.repeat(40);
 const manifest = { 'packages/krm-stream': '0.3.0', gateway: '0.3.0', 'gateway/kube': '0.3.0' };
@@ -112,3 +115,91 @@ test('registry outage during duplicate confirmation remains a failure', async ()
   await assert.rejects(publishWithRecovery({ version: '0.3.0', integrity,
     publish: async () => { throw duplicate(); }, fetcher: async () => response(503) }), /HTTP 503/);
 });
+
+const goResponse = (status, body = '') => ({ status, ok: status === 200, text: async () => body });
+const missingGoTag = (path = 'gateway', version = '0.3.0') =>
+  `not found: github.com/ConfigButler/krm-stream/${path}@v${version}: invalid version: unknown revision ${path}/v${version}`;
+
+test('Go readiness CLI requires an explicit release version before reading any local manifest', () => {
+  const env = { ...process.env };
+  delete env.VERSION;
+  const result = spawnSync(process.execPath, [fileURLToPath(new URL('./release.mjs', import.meta.url)), 'go-ready'], {
+    env, cwd: tmpdir(), encoding: 'utf8', timeout: 5_000,
+  });
+  assert.equal(result.status, 1);
+  assert.match(result.stderr, /go-ready requires an explicit VERSION from release preparation/);
+});
+
+test('Go readiness checks both release modules and validates the version before any request', async () => {
+  const urls = [];
+  const fetcher = async url => { urls.push(url); return goResponse(200); };
+  assert.equal(await goReleaseReady('0.3.0', fetcher), true);
+  assert.deepEqual(urls, [
+    'https://sum.golang.org/lookup/github.com/!config!butler/krm-stream/gateway@v0.3.0',
+    'https://sum.golang.org/lookup/github.com/!config!butler/krm-stream/gateway/kube@v0.3.0',
+  ]);
+  await assert.rejects(goReleaseReady('0.3.0/../../main', async () => assert.fail('unexpected request')));
+});
+
+test('only an exact missing-tag response for the requested module is a propagation delay', async () => {
+  for (const path of ['gateway', 'gateway/kube']) {
+    for (const status of [404, 410]) {
+      assert.equal(await goReleaseReady('0.3.0', async url => url.endsWith(`/${path}@v0.3.0`)
+        ? goResponse(status, missingGoTag(path)) : goResponse(200)), false);
+    }
+  }
+  for (const [status, body] of [
+    [404, ''], [404, missingGoTag('gateway', '0.2.1')], [404, missingGoTag('unrelated')],
+    [404, `${missingGoTag()}\nchecksum mismatch`], [403, missingGoTag()], [503, missingGoTag()],
+  ]) {
+    await assert.rejects(goReleaseReady('0.3.0', async () => goResponse(status, body)), /Go checksum lookup/);
+  }
+});
+
+test('a missing tag in one module cannot hide an unrelated error in the other', async () => {
+  for (const missingPath of ['gateway', 'gateway/kube']) {
+    await assert.rejects(waitForGoRelease('0.3.0', {
+      fetcher: async url => url.endsWith(`/${missingPath}@v0.3.0`)
+        ? goResponse(404, missingGoTag(missingPath)) : goResponse(503, 'service unavailable'),
+      wait: async () => assert.fail('unrelated errors must not wait'),
+    }), /HTTP 503/);
+  }
+  await assert.rejects(waitForGoRelease('0.3.0', {
+    fetcher: async () => { throw new Error('network down'); },
+    wait: async () => assert.fail('network errors must not wait'),
+  }), /network down/);
+});
+
+test('release preparation proceeds as soon as both checksum records are visible', async () => {
+  let reads = 0;
+  const waits = [];
+  await waitForGoRelease('0.3.0', {
+    fetcher: async () => ++reads === 1 ? goResponse(404, missingGoTag()) : goResponse(200),
+    wait: async ms => waits.push(ms),
+  });
+  assert.equal(reads, 4);
+  assert.deepEqual(waits, [60_000]);
+});
+
+test('ready releases do not wait', async () => {
+  await waitForGoRelease('0.3.0', {
+    fetcher: async () => goResponse(200),
+    wait: async () => assert.fail('ready records must not wait'),
+  });
+});
+
+test('the readiness deadline includes request time and never waits beyond the remaining budget', async () => {
+  let time = 0;
+  const waits = [];
+  await assert.rejects(waitForGoRelease('0.3.0', {
+    now: () => time,
+    fetcher: async url => {
+      time += 7_000;
+      return goResponse(404, missingGoTag(url.includes('/gateway/kube@') ? 'gateway/kube' : 'gateway'));
+    },
+    wait: async ms => { waits.push(ms); time += ms; },
+  }), /still missing after 30 minutes/);
+  assert.ok(waits.every(ms => ms > 0 && ms <= 60_000));
+  assert.ok(waits.at(-1) < 60_000);
+  assert.ok(waits.reduce((sum, ms) => sum + ms, 0) < 30 * 60_000);
+});
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 2bcdc0e..565904d 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -26,7 +26,7 @@ jobs:
     name: prepare the release
     if: github.ref == 'refs/heads/main'
     runs-on: ubuntu-latest
-    timeout-minutes: 10
+    timeout-minutes: 40
     permissions:
       contents: write
       pull-requests: write
@@ -57,6 +57,12 @@ jobs:
           VERSION: ${{ inputs.version || steps.release.outputs['packages/krm-stream--version'] }}
         run: node .github/scripts/release.mjs resolve
 
+      - name: wait for Go release checksum records
+        if: steps.target.outputs.needed == 'true'
+        env:
+          VERSION: ${{ steps.target.outputs.version }}
+        run: node .github/scripts/release.mjs go-ready
+
   ci:
     name: ci
     needs: prepare
diff --git a/docs/releasing.md b/docs/releasing.md
index 0f4f529..133c6f0 100644
--- a/docs/releasing.md
+++ b/docs/releasing.md
@@ -20,8 +20,9 @@ Nothing in it needs editing by hand.
    `@configbutler/krm-stream`.
 3. Merge the release pull request. `release.yml` then:
    1. lets Release Please create the tags and select the release commit;
-   2. validates and packs that commit once in CI, including a clean consumer of the public Go tag;
-   3. publishes to npm the tarball produced by that CI run.
+   2. waits for both Go modules' checksum records to become available;
+   3. validates and packs that commit once in CI, including a clean consumer of the public Go tag;
+   4. publishes to npm the tarball produced by that CI run.
 
 If a step fails, see [recovering a failed release](#recovering-a-failed-release).
 
@@ -99,7 +100,11 @@ npm version is published. Then:
   SHA-512 integrity matches the validated tarball. Other publish failures, unavailable metadata and
   mismatched artifacts still fail.
 - **The Go checksum database does not know the new tag yet** (`unknown revision gateway/vX.Y.Z`
-  shortly after tagging). Wait and rerun; do not bypass checksum verification.
+  shortly after tagging). Release preparation checks both modules' checksum lookups once a minute
+  for up to 30 minutes, covering the [Go module mirror's cache window](https://sum.golang.org/).
+  Only the exact response identifying a missing release tag is treated as a propagation delay;
+  other lookup errors fail immediately. The consumer check runs once with checksum verification
+  enabled. If the delay outlasts that window, wait and rerun the failed job.
 - **The tarball has expired.** Tarballs are kept for 30 days, matching
   [GitHub's job retry window](https://docs.github.com/en/actions/how-tos/manage-workflow-runs/re-run-workflows-and-jobs).
   An explicit recovery run rebuilds and validates once: