diff --git a/plugins/russian/ranobehub.ts b/plugins/russian/ranobehub.broken.ts
similarity index 100%
rename from plugins/russian/ranobehub.ts
rename to plugins/russian/ranobehub.broken.ts
diff --git a/tests/regression-2453.mjs b/tests/regression-2453.mjs
new file mode 100644
index 000000000..774958032
--- /dev/null
+++ b/tests/regression-2453.mjs
@@ -0,0 +1,106 @@
+#!/usr/bin/env node
+// Regression check for issue #2453: RanobeHub (RNBH.org) source retirement.
+//
+// The site ranobehub.org (and its successor ranobe.space) answers HTTP 451
+// "Domain closed" on every route (verified 2026-08-25), so the source is
+// retired to .broken.ts following the #1977 precedent. This script checks the
+// retirement invariants. It runs from the repo root:
+//
+//   node tests/regression-2453.mjs
+//
+// No npm dependencies. Uses node:fs and node:child_process only.
+//
+// RED baseline at base commit e1dcd06 (before the fix): T1 fails (no
+// .broken.ts file), T4 fails (content checks on a missing file). After the
+// fix: all four checks pass.
+
+import { readFileSync, existsSync, readdirSync } from 'node:fs';
+import { fileURLToPath } from 'node:url';
+import path from 'node:path';
+
+const root = path.resolve(path.dirname(fileURLToPath(import.meta.url)), '..');
+const oldFile = path.join(root, 'plugins', 'russian', 'ranobehub.ts');
+const retiredFile = path.join(
+  root,
+  'plugins',
+  'russian',
+  'ranobehub.broken.ts',
+);
+
+let failures = 0;
+function check(name, ok, detail = '') {
+  console.log(`${ok ? 'PASS' : 'FAIL'}  ${name}${ok ? '' : '  ' + detail}`);
+  if (!ok) failures += 1;
+}
+
+// T1 - retirement in place: the .broken.ts file exists, the original is gone.
+check('T1 retired file present', existsSync(retiredFile));
+check(
+  'T1 original file absent',
+  !existsSync(oldFile),
+  found(oldFile) ? 'old file still present' : 'ok state',
+);
+
+// T2 - the compile exclusions in both tsconfig files cover .broken.ts.
+for (const cfg of ['tsconfig.json', 'tsconfig.production.json']) {
+  let src = null;
+  try {
+    src = readFileSync(path.join(root, cfg), 'utf8');
+  } catch (e) {
+    src = '';
+  }
+  check(
+    `T2 ${cfg} excludes ./plugins/**/*.broken.ts`,
+    src.includes('./plugins/**/*.broken.ts'),
+  );
+}
+
+// T3 - no other committed source in the russian folder claims the RNBH.org id
+// (guards against a duplicate source sneaking in next to the retired one).
+const ruDir = path.join(root, 'plugins', 'russian');
+function found(p) {
+  try {
+    return existsSync(p);
+  } catch (e) {
+    return false;
+  }
+}
+let claimers = [];
+try {
+  claimers = readdirSync(ruDir)
+    .filter(f => f.endsWith('.ts'))
+    .filter(f => f !== 'ranobehub.broken.ts')
+    .filter(f =>
+      readFileSync(path.join(ruDir, f), 'utf8').includes("'RNBH.org'"),
+    );
+} catch (e) {
+  claimers = ['<plugins/russian unreadable>'];
+}
+check(
+  'T3 no other plugin claims RNBH.org',
+  claimers.length === 0,
+  claimers.join(', '),
+);
+
+// T4 - the retired file still documents the closed source lineage (id, name,
+// site). Guarded: if the file is missing (RED state), report FAIL without
+// crashing on the read.
+if (existsSync(retiredFile)) {
+  const src = readFileSync(retiredFile, 'utf8');
+  const docOk =
+    src.includes("id = 'RNBH.org'") &&
+    src.includes("name = 'RanobeHub'") &&
+    src.includes("site = 'https://ranobehub.org'");
+  check('T4 retired file documents id/name/site', docOk);
+} else {
+  check(
+    'T4 retired file documents id/name/site',
+    false,
+    'file missing (pre-rename)',
+  );
+}
+
+console.log(
+  failures === 0 ? '\nALL CHECKS PASS' : `\n${failures} CHECK(S) FAILED`,
+);
+process.exitCode = failures === 0 ? 0 : 1;