diff --git a/app.js b/app.js
index 2086ef7..f7cb031 100644
--- a/app.js
+++ b/app.js
@@ -112,6 +112,9 @@ global.syzoj = {
       this.db.sync();
     });
   },
+  lib(name) {
+    return require(`./libs/${name}`);
+  },
   model(name) {
     return require(`./models/${name}`);
   },
diff --git a/modules/enums.js b/libs/enums.js
similarity index 100%
rename from modules/enums.js
rename to libs/enums.js
diff --git a/modules/judge.js b/libs/judger.js
similarity index 100%
rename from modules/judge.js
rename to libs/judger.js
diff --git a/models/judge_state.js b/models/judge_state.js
index 2a78998..e2cb04f 100644
--- a/models/judge_state.js
+++ b/models/judge_state.js
@@ -20,13 +20,14 @@
 'use strict';
 
 let Sequelize = require('sequelize');
-const judger = require('../modules/judge');
 let db = syzoj.db;
 
 let User = syzoj.model('user');
 let Problem = syzoj.model('problem');
 let Contest = syzoj.model('contest');
 
+let Judger = syzoj.lib('judger');
+
 let model = db.define('judge_state', {
   id: { type: Sequelize.INTEGER, primaryKey: true, autoIncrement: true },
 
@@ -232,7 +233,7 @@ class JudgeState extends Model {
         await contest.newSubmission(this);
       }
 
-      await judger.judge(this, 1);
+      await Judger.judge(this, 1);
     });
   }
 
diff --git a/modules/api_v2.js b/modules/api_v2.js
index 2c2cb01..d081940 100644
--- a/modules/api_v2.js
+++ b/modules/api_v2.js
@@ -158,7 +158,7 @@ app.apiRouter.post('/api/v2/judge/peek', async (req, res) => {
 app.apiRouter.post('/api/v2/judge/compiled', async (req, res) => {
   try {
     if (req.get('Token') !== syzoj.config.judge_token) return res.status(403).send({ err: 'Incorrect token' });
-    const data = req.body;
+    let data = req.body;
 
     let JudgeState = syzoj.model('judge_state');
     let judge_state = await JudgeState.fromID(req.body.taskId);
diff --git a/modules/problem.js b/modules/problem.js
index c21b20a..2d358c9 100644
--- a/modules/problem.js
+++ b/modules/problem.js
@@ -28,7 +28,7 @@ let ProblemTag = syzoj.model('problem_tag');
 let ProblemTagMap = syzoj.model('problem_tag_map');
 let Article = syzoj.model('article');
 
-const judger = require('../modules/judge');
+let Judger = syzoj.lib('judger');
 
 app.get('/problems', async (req, res) => {
   try {
@@ -638,7 +638,7 @@ app.post('/problem/:id/submit', app.multer.fields([{ name: 'answer', maxCount: 1
     await judge_state.updateRelatedInfo(true);
 
     try {
-      await judger.judge(judge_state, contest_id ? 3 : 2);
+      await Judger.judge(judge_state, contest_id ? 3 : 2);
     } catch (err) {
       throw new ErrorMessage(`无法开始评测：${err.toString()}`);
     }