diff --git a/packages/migrate/index.ts b/packages/migrate/index.ts
index 412902685..04b2dab83 100644
--- a/packages/migrate/index.ts
+++ b/packages/migrate/index.ts
@@ -1,14 +1,48 @@
-import { Context, md5, sha1 } from 'hydrooj';
-import { apply as hustoj } from './scripts/hustoj';
-import { apply as syzoj } from './scripts/syzoj';
-import { apply as vijos } from './scripts/vijos';
+import {
+    Context, md5, Schema, sha1,
+} from 'hydrooj';
 
 const RE_MD5 = /^[\da-f]{32}$/;
 
 export function apply(ctx: Context) {
-    hustoj(ctx);
-    vijos(ctx);
-    syzoj(ctx);
+    ctx.addScript(
+        'migrateHustoj', 'migrate from hustoj',
+        Schema.object({
+            host: Schema.string().required(),
+            port: Schema.number().required(),
+            name: Schema.string().required(),
+            username: Schema.string().required(),
+            password: Schema.string().required(),
+            domainId: Schema.string().required(),
+            contestType: Schema.string().required(),
+            dataDir: Schema.string().required(),
+        }),
+        (...args) => require('./scripts/hustoj').run(...args),
+    );
+    ctx.addScript(
+        'migrateSyzoj', 'migrate from syzoj',
+        Schema.object({
+            host: Schema.string().required(),
+            port: Schema.number().required(),
+            name: Schema.string().required(),
+            username: Schema.string().required(),
+            password: Schema.string().required(),
+            domainId: Schema.string().default('system'),
+            dataDir: Schema.string().default('/opt/syzoj/web/uploads'),
+        }),
+        (...args) => require('./scripts/syzoj').run(...args),
+    );
+    ctx.addScript(
+        'migrateVijos', 'migrate from vijos',
+        Schema.object({
+            host: Schema.string().required(),
+            port: Schema.number().required(),
+            name: Schema.string().required(),
+            username: Schema.string().required(),
+            password: Schema.string().required(),
+        }),
+        (...args) => require('./scripts/vijos').run(...args),
+    );
 
     ctx.provideModule('hash', 'hust', ($password, $saved) => {
         $password = md5($password);
diff --git a/packages/migrate/scripts/hustoj.ts b/packages/migrate/scripts/hustoj.ts
index 484548f4c..423cc3a85 100644
--- a/packages/migrate/scripts/hustoj.ts
+++ b/packages/migrate/scripts/hustoj.ts
@@ -4,7 +4,7 @@ import mysql from 'mysql';
 import TurndownService from 'turndown';
 import {
     buildContent, ContestModel, DomainModel, fs, noop, NotFoundError, ObjectID, postJudge, ProblemModel,
-    RecordDoc, RecordModel, Schema, SolutionModel, STATUS, SystemModel, Time, UserModel,
+    RecordDoc, RecordModel, SolutionModel, STATUS, SystemModel, Time, UserModel,
 } from 'hydrooj';
 
 const turndown = new TurndownService({
@@ -298,18 +298,3 @@ export async function run({
     }
     return true;
 }
-
-export const apply = (ctx) => ctx.addScript(
-    'migrateHustoj', 'migrate from hustoj',
-    Schema.object({
-        host: Schema.string().required(),
-        port: Schema.number().required(),
-        name: Schema.string().required(),
-        username: Schema.string().required(),
-        password: Schema.string().required(),
-        domainId: Schema.string().required(),
-        contestType: Schema.string().required(),
-        dataDir: Schema.string().required(),
-    }),
-    run,
-);
diff --git a/packages/migrate/scripts/syzoj.ts b/packages/migrate/scripts/syzoj.ts
index d2e90913d..e6c91aa32 100644
--- a/packages/migrate/scripts/syzoj.ts
+++ b/packages/migrate/scripts/syzoj.ts
@@ -3,7 +3,7 @@ import mariadb from 'mariadb';
 import {
     buildContent, ContestModel, DiscussionDoc, DiscussionReplyDoc, DocumentModel, DomainModel,
     fs, noop, NotFoundError, ObjectID, PERM, postJudge, ProblemModel, RecordDoc, RecordModel,
-    Schema, STATUS, SystemModel, Time, UserModel, yaml,
+    STATUS, SystemModel, Time, UserModel, yaml,
 } from 'hydrooj';
 
 const contentTypeMap = {
@@ -496,17 +496,3 @@ export async function run({
     }
     return true;
 }
-
-export const apply = (ctx) => ctx.addScript(
-    'migrateSyzoj', 'migrate from syzoj',
-    Schema.object({
-        host: Schema.string().required(),
-        port: Schema.number().required(),
-        name: Schema.string().required(),
-        username: Schema.string().required(),
-        password: Schema.string().required(),
-        domainId: Schema.string().default('system'),
-        dataDir: Schema.string().default('/opt/syzoj/web/uploads'),
-    }),
-    run,
-);
diff --git a/packages/migrate/scripts/vijos.ts b/packages/migrate/scripts/vijos.ts
index 4fdbc1396..075f1d494 100644
--- a/packages/migrate/scripts/vijos.ts
+++ b/packages/migrate/scripts/vijos.ts
@@ -4,7 +4,7 @@ import mongodb, { Cursor, Db } from 'mongodb';
 import {
     db as dst,
     DiscussionModel, DiscussionTailReplyDoc, DocumentModel,
-    MessageDoc, RecordDoc, Schema, TestCase, TrainingNode,
+    MessageDoc, RecordDoc, TestCase, TrainingNode,
 } from 'hydrooj';
 
 const map = {};
@@ -503,15 +503,3 @@ export async function run({
     await global.Hydro.model.system.set('db.ver', 1);
     return true;
 }
-
-export const apply = (ctx) => ctx.addScript(
-    'migrateVijos', 'migrate from vijos',
-    Schema.object({
-        host: Schema.string().required(),
-        port: Schema.number().required(),
-        name: Schema.string().required(),
-        username: Schema.string().required(),
-        password: Schema.string().required(),
-    }),
-    run,
-);