diff --git a/.changeset/tender-hairs-grab.md b/.changeset/tender-hairs-grab.md
new file mode 100644
index 00000000..eb7713c3
--- /dev/null
+++ b/.changeset/tender-hairs-grab.md
@@ -0,0 +1,5 @@
+---
+"nxjs-runtime": patch
+---
+
+Support arbitrary key name length in `localStorage`
diff --git a/packages/runtime/src/$.ts b/packages/runtime/src/$.ts
index a0202c65..ccb077d0 100644
--- a/packages/runtime/src/$.ts
+++ b/packages/runtime/src/$.ts
@@ -118,6 +118,7 @@ export interface Init {
 	// crypto.c
 	cryptoDigest(algorithm: string, buf: ArrayBuffer): Promise<ArrayBuffer>;
 	cryptoRandomBytes(buf: ArrayBuffer, offset: number, length: number): void;
+	sha256Hex(str: string): string;
 
 	// dommatrix.c
 	dommatrixNew(values?: number[]): DOMMatrix | DOMMatrixReadOnly;
diff --git a/packages/runtime/src/storage.ts b/packages/runtime/src/storage.ts
index e4f86cc8..2fc5c9da 100644
--- a/packages/runtime/src/storage.ts
+++ b/packages/runtime/src/storage.ts
@@ -1,21 +1,17 @@
-import {
-	readDirSync,
-	readFileSync,
-	removeSync,
-	statSync,
-	writeFileSync,
-} from './fs';
+import { $ } from './$';
+import { readFileSync, removeSync, writeFileSync } from './fs';
 import { URL } from './polyfills/url';
 import { Profile } from './switch/profile';
 import { Application } from './switch/ns';
 import { INTERNAL_SYMBOL } from './internal';
 import {
+	def,
 	assertInternalConstructor,
 	createInternal,
 	decodeUTF16,
-	def,
 	encodeUTF16,
 } from './utils';
+import { decoder } from './polyfills/text-decoder';
 
 interface StorageImpl {
 	clear(): void;
@@ -137,52 +133,52 @@ Object.defineProperty(globalThis, 'localStorage', {
 			saveData = self.createProfileSaveDataSync(profile);
 		}
 		const base = new URL('localStorage/', saveData.mount());
+		const keyMapUrl = new URL('keys.json', base);
+		let keyMap: Record<string, string> = (() => {
+			const keyMapBuffer = readFileSync(keyMapUrl);
+			if (!keyMapBuffer) return {};
+			return JSON.parse(decoder.decode(keyMapBuffer));
+		})();
 
-		const keyToPath = (key: any) => {
-			const url = `${base.href}_${Array.from(String(key))
-				.map((l) => l.charCodeAt(0).toString(16))
-				.join('_')}`;
-			return url;
-		};
-
-		const pathToKey = (path: string) => {
-			const key = String.fromCharCode(
-				...path
-					.slice(1)
-					.split('_')
-					.map((h) => parseInt(h, 16)),
-			);
-			return key;
-		};
+		const keyDigest = (key: any) => $.sha256Hex(String(key));
 
 		const impl: StorageImpl = {
 			clear() {
+				keyMap = {};
 				removeSync(base);
 				saveData!.commit();
 			},
 			getItem(key: string): string | null {
-				const b = readFileSync(keyToPath(key));
+				const d = keyDigest(key);
+				const b = readFileSync(new URL(d, base));
 				if (!b) return null;
 				return decodeUTF16(b);
 			},
 			key(index: number): string | null {
 				if (index < 0) return null;
 				const i = index % 0x100000000;
-				const keys = readDirSync(base) || [];
-				if (i >= keys.length) return null;
-				return pathToKey(keys[i]);
+				const v = Object.values(keyMap);
+				if (i >= v.length) return null;
+				return v[i] ?? null;
 			},
 			removeItem(key: string): void {
-				removeSync(keyToPath(key));
+				const d = keyDigest(key);
+				removeSync(new URL(d, base));
+				delete keyMap[d];
+				writeFileSync(keyMapUrl, JSON.stringify(keyMap));
 				saveData!.commit();
 			},
 			setItem(key: string, value: string): void {
-				writeFileSync(keyToPath(key), encodeUTF16(String(value)));
+				const d = keyDigest(key);
+				writeFileSync(new URL(d, base), encodeUTF16(String(value)));
+				if (!keyMap[d]) {
+					keyMap[d] = key;
+					writeFileSync(keyMapUrl, JSON.stringify(keyMap));
+				}
 				saveData!.commit();
 			},
 			length(): number {
-				const keys = readDirSync(base);
-				return keys ? keys.length : 0;
+				return Object.keys(keyMap).length;
 			},
 		};
 		// @ts-expect-error internal constructor
@@ -190,8 +186,7 @@ Object.defineProperty(globalThis, 'localStorage', {
 		const proxy = new Proxy(storage, {
 			has(_, p) {
 				if (typeof p !== 'string') return false;
-				const s = statSync(keyToPath(p));
-				return s !== null;
+				return !!Object.values(keyMap).find((k) => k === p);
 			},
 			get(target, p) {
 				if (typeof p !== 'string') return undefined;
@@ -211,7 +206,7 @@ Object.defineProperty(globalThis, 'localStorage', {
 				return true;
 			},
 			ownKeys() {
-				return (readDirSync(base) || []).map((p) => pathToKey(p));
+				return Object.values(keyMap);
 			},
 			getOwnPropertyDescriptor(target, p) {
 				if (typeof p !== 'string') return;
diff --git a/source/crypto.c b/source/crypto.c
index d6deb69d..b84cfe22 100644
--- a/source/crypto.c
+++ b/source/crypto.c
@@ -96,9 +96,32 @@ static JSValue nx_crypto_random_bytes(JSContext *ctx, JSValueConst this_val,
 	return JS_UNDEFINED;
 }
 
+static JSValue nx_crypto_sha256_hex(JSContext *ctx, JSValueConst this_val,
+									int argc, JSValueConst *argv) {
+	size_t size;
+	const char *str = JS_ToCStringLen(ctx, &size, argv[0]);
+	if (!str) {
+		return JS_EXCEPTION;
+	}
+	u8 *digest = js_mallocz(ctx, SHA256_HASH_SIZE);
+	if (!digest) {
+		return JS_EXCEPTION;
+	}
+	sha256CalculateHash(digest, str, size);
+	JS_FreeCString(ctx, str);
+	char hex[SHA256_HASH_SIZE * 2 + 1];
+	for (int i = 0; i < SHA256_HASH_SIZE; i++) {
+		snprintf(hex + i * 2, 3, "%02x", digest[i]);
+	}
+	JSValue hex_val = JS_NewString(ctx, hex);
+	js_free(ctx, digest);
+	return hex_val;
+}
+
 static const JSCFunctionListEntry function_list[] = {
 	JS_CFUNC_DEF("cryptoDigest", 0, nx_crypto_digest),
 	JS_CFUNC_DEF("cryptoRandomBytes", 0, nx_crypto_random_bytes),
+	JS_CFUNC_DEF("sha256Hex", 0, nx_crypto_sha256_hex),
 };
 
 void nx_init_crypto(JSContext *ctx, JSValueConst init_obj) {