diff --git a/packages/utils/lib/lang.ts b/packages/utils/lib/lang.ts
index 1b997ba95..52e16728d 100644
--- a/packages/utils/lib/lang.ts
+++ b/packages/utils/lib/lang.ts
@@ -7,6 +7,7 @@ export interface LangConfig {
     highlight: string;
     monaco: string;
     time_limit_rate: number;
+    domain: string[];
     display: string;
     target?: string;
     sub?: LangConfig[];
diff --git a/packages/utils/lib/utils.ts b/packages/utils/lib/utils.ts
index 630477628..e7d0a3461 100644
--- a/packages/utils/lib/utils.ts
+++ b/packages/utils/lib/utils.ts
@@ -31,11 +31,11 @@ declare global {
     }
 }
 
-const dict = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890';
+const defaultDict = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890';
 
-String.random = function random(digit = 32) {
+String.random = function random(digit = 32, dict = defaultDict) {
     let str = '';
-    for (let i = 1; i <= digit; i++) str += dict[Math.floor(Math.random() * 62)];
+    for (let i = 1; i <= digit; i++) str += dict[Math.floor(Math.random() * dict.length)];
     return str;
 };
 
diff --git a/packages/utils/package.json b/packages/utils/package.json
index 9b809c4f8..11b5be79c 100644
--- a/packages/utils/package.json
+++ b/packages/utils/package.json
@@ -1,6 +1,6 @@
 {
     "name": "@hydrooj/utils",
-    "version": "1.0.21",
+    "version": "1.0.22",
     "description": "hydrooj utils",
     "main": "package.json",
     "repository": "https://github.com/hydro-dev/Hydro.git",