diff --git a/lib/__tests__/lite-scripts.test.ts b/lib/__tests__/lite-scripts.test.ts
index 8e103daa4..1262e7206 100644
--- a/lib/__tests__/lite-scripts.test.ts
+++ b/lib/__tests__/lite-scripts.test.ts
@@ -58,6 +58,8 @@ import {
   stalwartPrefixProblems,
   stalwartRewriteIndex,
   stalwartZipEntryProblems,
+  unexpectedEngineFiles,
+  LITE_REMOVED_PATHS,
   unexpectedApiStrings,
   withScriptHashCsp,
 } from '../../scripts/lite/lib.mjs';
@@ -342,6 +344,33 @@ describe('lite build helpers', () => {
   });
 });
 
+describe('the local store in an export', () => {
+  it('finds every engine file, and nothing else', () => {
+    expect(unexpectedEngineFiles([
+      'store-worker.js',
+      'sqlite3mc/2.6.1-3.54.0/sqlite3.mjs',
+      'sqlite3mc\\2.6.1-3.54.0\\sqlite3.wasm',
+      '_next/static/media/sqlite3.wasm',
+      'pst-worker.js',
+      'en/mail/index.html',
+      '_next/static/chunks/app.js',
+    ])).toEqual([
+      'store-worker.js',
+      'sqlite3mc/2.6.1-3.54.0/sqlite3.mjs',
+      'sqlite3mc/2.6.1-3.54.0/sqlite3.wasm',
+      '_next/static/media/sqlite3.wasm',
+    ]);
+  });
+
+  it('removes what a dev checkout holds before a build, and offline mode never starts in Lite', () => {
+    expect(LITE_REMOVED_PATHS).toEqual(expect.arrayContaining(['public/store-worker.js', 'public/sqlite3mc']));
+    const offlineMode = readFileSync(join(process.cwd(), 'lib/offline/offline-mode.ts'), 'utf8');
+    expect(offlineMode).toMatch(/if \(IS_LITE \|\| !hasIndexedDb\(\)\) return false;/);
+    const build = readFileSync(join(process.cwd(), 'scripts/lite/build.mjs'), 'utf8');
+    expect(build).not.toMatch(/build-store-worker/);
+  });
+});
+
 describe('prepare / postbuild / verify against a fake checkout', () => {
   it('plans the server-only trees and every test file, skipping node_modules, repos and scripts', () => {
     const root = makeRepo();
diff --git a/scripts/lite/lib.mjs b/scripts/lite/lib.mjs
index 18bdc6cdf..9f64367d7 100644
--- a/scripts/lite/lib.mjs
+++ b/scripts/lite/lib.mjs
@@ -48,6 +48,13 @@ export const LITE_REMOVED_PATHS = [
   "public/sqlite3mc",
 ];
 
+/** The local store's engine in an export: Lite has no offline mode, and must not ship or load it. */
+export function unexpectedEngineFiles(files) {
+  return files
+    .map((file) => file.replace(/\\/g, "/"))
+    .filter((file) => /(^|\/)store-worker\.js$/.test(file) || /(^|\/)sqlite3mc\//.test(file) || /(^|\/)sqlite3\.(wasm|mjs)$/.test(file));
+}
+
 /** Test trees are pruned too: they import the routes removed above. */
 export const LITE_TEST_DIR_NAME = "__tests__";
 export const LITE_TEST_FILE_PATTERN = /\.test\.[cm]?[jt]sx?$/;
diff --git a/scripts/lite/verify.mjs b/scripts/lite/verify.mjs
index 3e2800168..4a19c6e30 100644
--- a/scripts/lite/verify.mjs
+++ b/scripts/lite/verify.mjs
@@ -10,7 +10,7 @@ import { existsSync, readFileSync, statSync } from "node:fs";
 import { join } from "node:path";
 import {
   LITE_PENDING_PATH_KEY, STALWART_EXCLUDED_FILES, STALWART_MAX_BUNDLE_BYTES, STALWART_SAFE_BUNDLE_BYTES, STALWART_ZIP_NAME,
-  collectApiStrings, collectZipEntries, discoverBuiltLocales, flightTextRowsWithNeedles, inlineScriptHashes, isMainModule, listZipEntries, parseLiteTarget, resolveRepoRoot, stalwartEntryProblems, stalwartZipEntryProblems, unexpectedApiStrings,
+  collectApiStrings, collectZipEntries, discoverBuiltLocales, flightTextRowsWithNeedles, inlineScriptHashes, isMainModule, listZipEntries, parseLiteTarget, resolveRepoRoot, stalwartEntryProblems, stalwartZipEntryProblems, unexpectedApiStrings, unexpectedEngineFiles,
 } from "./lib.mjs";
 
 const repoRoot = resolveRepoRoot(import.meta.url);
@@ -83,6 +83,10 @@ export function verifyExport({ root = repoRoot, target, safeBundleBytes = STALWA
   const unexpected = unexpectedApiStrings(apiStrings);
   for (const s of unexpected) problems.push(`client chunk references undocumented server endpoint ${s} (add an IS_LITE gate or document it in scripts/lite/lib.mjs)`);
 
+  if (existsSync(outDir)) {
+    for (const file of unexpectedEngineFiles(collectZipEntries(outDir).map(({ name }) => name))) problems.push(`out/${file} is the local store's engine, which Lite must not ship`);
+  }
+
   let zipBytes = 0;
   if (resolvedTarget === "stalwart") {
     const entry = join(outDir, "index.html");