diff --git a/web/boot/index.html b/web/boot/index.html
new file mode 100644
index 00000000..9cc47226
--- /dev/null
+++ b/web/boot/index.html
@@ -0,0 +1,56 @@
+<!DOCTYPE html>
+<html lang="en">
+
+<head>
+    <meta charset="UTF-8">
+    <title>Kiri:Moto (loading)</title>
+    <style>
+        body {
+            top: 0;
+            left: 0;
+            right: 0;
+            bottom: 0;
+            display: flex;
+            position: fixed;
+            align-items: center;
+            flex-direction: column;
+            justify-content: center;
+            font-family: sans-serif;
+            font-weight: bold;
+        }
+    </style>
+    <script>
+        (async () => {
+            const reg = await navigator.serviceWorker.register('/boot/service.js', { scope: '/' });
+            await reg.update();
+            await navigator.serviceWorker.ready;
+
+            if (!navigator.serviceWorker.controller) {
+                console.log('No controller → reloading under SW control');
+                location.reload();
+                return;
+            }
+
+            navigator.serviceWorker.controller.postMessage({
+                mode: 'cached',
+                version: 1
+            });
+
+            navigator.serviceWorker.addEventListener('message', e => {
+                if (e.data === 'preload-complete') {
+                    console.log('preload complete');
+                    location.replace('/kiri/index.html');
+                } else if (e.data === 'preload-cached') {
+                    console.log('preload cached');
+                    location.replace('/kiri/index.html');
+                }
+            });
+        })();
+    </script>
+</head>
+
+<body>
+    Kiri:Moto is Loading
+</body>
+
+</html>
\ No newline at end of file
diff --git a/web/boot/service.js b/web/boot/service.js
new file mode 100644
index 00000000..be51a7ae
--- /dev/null
+++ b/web/boot/service.js
@@ -0,0 +1,177 @@
+// --- configurable ---
+const CACHE_VERSION = 'kiri-v001';
+const BUNDLE_URL = '/kiri/bundle.bin';
+const VERSION_KEY = '/__version__';
+
+let mode = 'cached';
+let currentVersion = null;
+
+// --- logging ---
+const log = (...a) => console.log('[SW]', ...a);
+self.addEventListener('install', e => log('install'));
+self.addEventListener('activate', e => log('activate'));
+// self.addEventListener('fetch', e => log('fetch', e.request.url));
+
+// --- lifecycle ---
+self.skipWaiting();
+self.addEventListener('activate', e => e.waitUntil(clients.claim()));
+
+// --- mode control ---
+self.addEventListener('message', e => {
+    log({ message: e.data });
+    const data = e.data || {};
+    if (data.mode) mode = data.mode;
+    if (data.mode === 'cached' && data.version !== undefined) {
+        ensureVersion(data.version);
+    }
+});
+
+// --- version check and preload ---
+async function ensureVersion(incomingVersion) {
+    const cache = await caches.open(CACHE_VERSION);
+    let needPreload = false;
+
+    const existing = await cache.match(VERSION_KEY);
+    if (!existing) {
+        log('no version stored → preload');
+        needPreload = true;
+    } else {
+        const text = await existing.text();
+        const stored = parseInt(text, 10);
+        if (stored !== incomingVersion) {
+            log(`version mismatch ${stored} ≠ ${incomingVersion} → preload`);
+            needPreload = true;
+        } else {
+            log(`version OK (${stored})`);
+        }
+    }
+
+    if (needPreload) {
+        await preloadBundle();
+        await cache.put(
+            VERSION_KEY,
+            new Response(String(incomingVersion), { headers: { 'Content-Type': 'text/plain' } })
+        );
+        broadcast('preload-complete');
+    } else {
+        broadcast('preload-cached');
+    }
+}
+
+// --- fetch with redirect handler ---
+async function fetch_safe(req) {
+    const res = await fetch(req);
+    if (res.redirected) {
+        log({ was_redirected_cloning: res.url });
+        // clone into a fresh non-redirect response
+        const clone = res.clone();
+        return new Response(await clone.blob(), {
+            headers: clone.headers,
+            status: 200,
+            statusText: 'OK'
+        });
+    }
+    return res;
+}
+
+// --- fetch handler ---
+self.addEventListener('fetch', e => {
+    const { request } = e;
+    const url = new URL(request.url);
+
+    if (request.method !== 'GET') return;
+
+    if (mode === 'transparent') {
+        e.respondWith(fetch_safe(e.request));
+        return;
+    }
+
+    e.respondWith(fromCacheOrNetwork(request));
+});
+
+// --- helpers ---
+async function fromCacheOrNetwork(req) {
+    const cache = await caches.open(CACHE_VERSION);
+    const hit = await cache.match(req);
+    if (hit) {
+        // log({ hit: hit.url || req.url });
+        return hit;
+    }
+    const net = await fetch_safe(req);
+    cache.put(req, net.clone());
+    log({ put: net.url });
+    return net;
+}
+
+async function serveIndex() {
+    const cache = await caches.open(CACHE_VERSION);
+    const hit = await cache.match('/kiri/index.html');
+    log({ serve_index: hit, cache });
+    if (hit) return hit;
+    return fetch_safe('/kiri/index.html');
+}
+
+async function broadcast(message) {
+    const clientsList = await clients.matchAll({ type: 'window' });
+    for (const client of clientsList) {
+        client.postMessage(message);
+    }
+}
+
+const sec_headers = {
+    'Cross-Origin-Opener-Policy': 'same-origin',
+    'Cross-Origin-Embedder-Policy': 'require-corp'
+};
+
+// --- preload & unpack bundle ---
+async function preloadBundle() {
+    // return;
+    const cache = await caches.open(CACHE_VERSION);
+    const res = await fetch(BUNDLE_URL, { cache: 'no-store' });
+    const buf = await res.arrayBuffer();
+    const files = await unpackBundle(buf);
+    log({ files });
+    await Promise.all(
+        Object.entries(files).map(([path, blob]) => {
+            const ext = path.split('.').pop();
+            const type =
+                ext === 'html' ? 'text/html' :
+                ext === 'js' ? 'application/javascript' :
+                ext === 'css' ? 'text/css' :
+                ext === 'json' ? 'application/json' :
+                ext === 'wasm' ? 'application/wasm' :
+                ext === 'svg' ? 'image/svg+xml' :
+                        'application/octet-stream';
+            const headers = { 'Content-Type': type, ...sec_headers };
+            // Object.assign(headers, sec_headers);
+            const resp = new Response(blob, { headers });
+            return cache.put('/' + path, resp);
+        })
+    );
+}
+
+// --- simple bundle format ---
+// [count:uint32][entries...][file data...]
+// entry: [nlen:uint16][name][offset:uint32][length:uint32]
+async function unpackBundle(buf) {
+    const view = new DataView(buf);
+    let pos = 0;
+    const count = view.getUint32(pos, true); pos += 4;
+    const decoder = new TextDecoder();
+    const table = [];
+
+    for (let i = 0; i < count; i++) {
+        const nlen = view.getUint16(pos, true); pos += 2;
+        const name = decoder.decode(new Uint8Array(buf, pos, nlen)); pos += nlen;
+        const offset = view.getUint32(pos, true); pos += 4;
+        const len = view.getUint32(pos, true); pos += 4;
+        table.push({ name, offset, len });
+    }
+    log({ table });
+
+    const files = {};
+    for (const { name, offset, len } of table)
+        files[name] = buf.slice(offset, offset + len);
+
+    return files;
+}