diff --git a/packages/hydrooj/package.json b/packages/hydrooj/package.json
index f6e80169..82b189b0 100644
--- a/packages/hydrooj/package.json
+++ b/packages/hydrooj/package.json
@@ -1,6 +1,6 @@
 {
     "name": "hydrooj",
-    "version": "2.28.44",
+    "version": "2.28.45",
     "bin": "bin/hydrooj.js",
     "main": "dist/loader.js",
     "typings": "dist/loader.d.ts",
@@ -12,7 +12,7 @@
     },
     "preferUnplugged": true,
     "dependencies": {
-        "@hydrooj/utils": "workspace:*",
+        "@hydrooj/utils": "workspace:packages/utils",
         "adm-zip": "^0.5.5",
         "ansi_up": "^5.0.1",
         "cac": "^6.7.3",
diff --git a/packages/hydrooj/src/handler/contest.ts b/packages/hydrooj/src/handler/contest.ts
index 65c6a667..2d571588 100644
--- a/packages/hydrooj/src/handler/contest.ts
+++ b/packages/hydrooj/src/handler/contest.ts
@@ -295,7 +295,8 @@ export class ContestProblemHandler extends Handler {
         // Navigate to current additional file download
         // e.g. ![img](a.jpg) will navigate to ![img](./pid/file/a.jpg)
         this.response.body.pdoc.content = this.response.body.pdoc.content
-            .replace(/\(file:\/\//g, `(./${args[2]}/file/`);
+            .replace(/\(file:\/\//g, `(./${args[2]}/file/`)
+            .replace(/="file:\/\//g, `="./${args[2]}/file/`);
     }
 }
 
@@ -344,6 +345,9 @@ export class ContestDetailProblemSubmitHandler extends ContestProblemHandler {
         if (this.response.body.pdoc.config?.langs && !this.response.body.pdoc.config.langs.includes(lang)) {
             throw new BadRequestError('Language not allowed.');
         }
+        if (this.domain.langs && !this.domain.langs.includes(lang)) {
+            throw new BadRequestError('Language not allowed');
+        }
         await this.limitRate('add_record', 60, 10);
         const rid = await record.add(domainId, pid, this.user._id, lang, code, true, pretest ? input : {
             type: document.TYPE_CONTEST,
diff --git a/packages/hydrooj/src/handler/homework.ts b/packages/hydrooj/src/handler/homework.ts
index 53271dec..3e760c90 100644
--- a/packages/hydrooj/src/handler/homework.ts
+++ b/packages/hydrooj/src/handler/homework.ts
@@ -168,7 +168,8 @@ class HomeworkDetailProblemHandler extends Handler {
         // Navigate to current additional file download
         // e.g. ![img](a.jpg) will navigate to ![img](./pid/file/a.jpg)
         this.response.body.pdoc.content = this.response.body.pdoc.content
-            .replace(/\(file:\/\//g, `(./${pid}/file/`);
+            .replace(/\(file:\/\//g, `(./${pid}/file/`)
+            .reaplce(/="file:\/\//g, `="./${pid}/file/`);
     }
 }
 
@@ -219,6 +220,9 @@ class HomeworkDetailProblemSubmitHandler extends HomeworkDetailProblemHandler {
         if (this.response.body.pdoc.config?.langs && !this.response.body.pdoc.config.langs.includes(lang)) {
             throw new BadRequestError('Language not allowed.');
         }
+        if (this.domain.langs && !this.domain.langs.includes(lang)) {
+            throw new BadRequestError('Language not allowed');
+        }
         await this.limitRate('add_record', 60, 5);
         const rid = await record.add(domainId, pid, this.user._id, lang, code, true, pretest ? input : {
             type: document.TYPE_HOMEWORK,
diff --git a/packages/hydrooj/src/handler/problem.ts b/packages/hydrooj/src/handler/problem.ts
index 854a7299..79557a44 100644
--- a/packages/hydrooj/src/handler/problem.ts
+++ b/packages/hydrooj/src/handler/problem.ts
@@ -212,7 +212,8 @@ export class ProblemDetailHandler extends ProblemHandler {
         // e.g. ![img](a.jpg) will navigate to ![img](./pid/file/a.jpg)
         if (!this.request.json) {
             this.response.body.pdoc.content = this.response.body.pdoc.content
-                .replace(/\(file:\/\//g, `(./${this.pdoc.docId}/file/`);
+                .replace(/\(file:\/\//g, `(./${this.pdoc.docId}/file/`)
+                .replace(/="file:\/\//g, `="./${this.pdoc.docId}/file/`);
         }
         if (this.psdoc) {
             this.response.body.rdoc = await record.get(this.domainId, this.psdoc.rid);
@@ -269,6 +270,9 @@ export class ProblemSubmitHandler extends ProblemDetailHandler {
         if (this.response.body.pdoc.config?.langs && !this.response.body.pdoc.config.langs.includes(lang)) {
             throw new BadRequestError('Language not allowed.');
         }
+        if (this.domain.langs && !this.domain.langs.includes(lang)) {
+            throw new BadRequestError('Language not allowed');
+        }
         await this.limitRate('add_record', 60, 5);
         const rid = await record.add(domainId, this.pdoc.docId, this.user._id, lang, code, true, pretest ? input : undefined);
         const rdoc = await record.get(domainId, rid);
diff --git a/packages/hydrooj/src/interface.ts b/packages/hydrooj/src/interface.ts
index 61039d42..18ac4283 100644
--- a/packages/hydrooj/src/interface.ts
+++ b/packages/hydrooj/src/interface.ts
@@ -136,15 +136,19 @@ export enum SubtaskType {
 }
 
 export interface SubtaskConfig {
-    time?: number,
-    memory?: number,
-    score?: number,
-    type?: SubtaskType,
-    cases?: TestCaseConfig[],
+    time?: number;
+    memory?: number;
+    score?: number;
+    if?: number[];
+    id?: number;
+    type?: SubtaskType;
+    cases?: TestCaseConfig[];
 }
 
 export interface ProblemConfigFile {
     type?: ProblemType;
+    subType?: string;
+    target?: string;
     score?: number;
     time?: string;
     memory?: string;
@@ -168,6 +172,8 @@ export interface ProblemConfig {
     timeMin: number;
     langs?: string[];
     type: string;
+    subType?: string;
+    target?: string;
 }
 
 export interface PlainContentNode {
diff --git a/packages/hydrooj/src/lib/content.ts b/packages/hydrooj/src/lib/content.ts
index f47f8d7f..ef23f0f7 100644
--- a/packages/hydrooj/src/lib/content.ts
+++ b/packages/hydrooj/src/lib/content.ts
@@ -26,15 +26,20 @@ export function buildContent(source: ProblemSource | ContentNode[], type: 'markd
                 node.type !== 'Plain' ? `## ${node.sectionTitle}` : '',
                 ...node.type === 'Sample'
                     ? [
+                        '',
                         `\`\`\`input${++cnt}`,
                         node.payload[0],
                         '```',
+                        '',
                         `\`\`\`output${cnt}`,
                         node.payload[1],
                         '```',
+                        '',
                     ]
                     : [],
+                '',
                 node.text,
+                '',
             ].join('\n')).join('\n');
     }
     return type === 'html'
diff --git a/packages/hydrooj/src/lib/testdataConfig.ts b/packages/hydrooj/src/lib/testdataConfig.ts
index 969d231c..d0f49f41 100644
--- a/packages/hydrooj/src/lib/testdataConfig.ts
+++ b/packages/hydrooj/src/lib/testdataConfig.ts
@@ -16,6 +16,8 @@ export async function parseConfig(config: string | ProblemConfigFile = {}) {
         timeMax: 0,
         type: cfg.type || 'default',
     };
+    if (cfg.subType) result.subType = cfg.subType;
+    if (cfg.target) result.target = cfg.target;
     if (cfg.subtasks.length) {
         for (const subtask of cfg.subtasks) {
             result.memoryMax = Math.max(result.memoryMax, subtask.memory);
diff --git a/packages/hydrooj/src/model/problem.ts b/packages/hydrooj/src/model/problem.ts
index efc7e44b..77f145d5 100644
--- a/packages/hydrooj/src/model/problem.ts
+++ b/packages/hydrooj/src/model/problem.ts
@@ -39,7 +39,7 @@ export class ProblemModel {
         domainId: 'system',
         docType: document.TYPE_PROBLEM,
         docId: 0,
-        pid: null,
+        pid: '',
         owner: 1,
         title: '*',
         content: '',
diff --git a/packages/hydrooj/src/model/record.ts b/packages/hydrooj/src/model/record.ts
index ba70e7aa..5a9a561e 100644
--- a/packages/hydrooj/src/model/record.ts
+++ b/packages/hydrooj/src/model/record.ts
@@ -9,7 +9,7 @@ import { STATUS } from './builtin';
 import task from './task';
 import problem from './problem';
 import {
-    RecordDoc, ContestInfo, ProblemConfigFile, ExternalProblemId,
+    RecordDoc, ContestInfo, ProblemConfigFile, ExternalProblemId, ProblemConfig,
 } from '../interface';
 import { ArgMethod, buildProjection, Time } from '../utils';
 import { MaybeArray } from '../typeutils';
@@ -62,11 +62,25 @@ class RecordModel {
     static async judge(domainId: string, rid: ObjectID, priority = 0, config: ProblemConfigFile = {}) {
         const rdoc = await RecordModel.get(domainId, rid);
         let data = [];
+        delete rdoc._id;
         if (rdoc.pid) {
             const pdoc = await problem.get(rdoc.pdomain, rdoc.pid);
             data = pdoc.data;
+            if (typeof pdoc.config === 'string') throw new Error(); // Just for typings. This won't happen.
+            if (pdoc.config.type === 'remote_judge') {
+                return await task.add({
+                    ...rdoc,
+                    priority,
+                    type: 'remotejudge',
+                    subType: pdoc.config.subType,
+                    target: pdoc.config.target,
+                    rid,
+                    domainId,
+                    config,
+                    data,
+                });
+            }
         }
-        delete rdoc._id;
         await task.add({
             ...rdoc,
             priority,
diff --git a/packages/hydrooj/src/model/setting.ts b/packages/hydrooj/src/model/setting.ts
index 25e9c5b9..2584cedd 100644
--- a/packages/hydrooj/src/model/setting.ts
+++ b/packages/hydrooj/src/model/setting.ts
@@ -140,6 +140,7 @@ DomainSetting(
     Setting('setting_domain', 'avatar', '', 'text', 'avatar', 'Will be used as the domain icon.'),
     Setting('setting_domain', 'share', '', 'text', 'Share problem with domain (* for any)'),
     Setting('setting_domain', 'bulletin', '', 'markdown', 'Bulletin'),
+    Setting('setting_domain', 'langs', '', 'text', 'Allowed langs', null),
     Setting('setting_storage', 'host', '', 'text', 'Custom host', null, FLAG_HIDDEN | FLAG_DISABLED),
 );
 
diff --git a/packages/hydrooj/src/service/server.ts b/packages/hydrooj/src/service/server.ts
index 102de8f2..50056552 100644
--- a/packages/hydrooj/src/service/server.ts
+++ b/packages/hydrooj/src/service/server.ts
@@ -503,6 +503,7 @@ export class Handler extends HandlerCommon {
             throw new NotFoundError(domainId);
         }
         this.UiContext.domainId = this.domainId;
+        this.UiContext.domain = this.domain;
         this.user = await user.getById(domainId, this.session.uid, this.session.scope);
         if (!this.user) {
             this.session.uid = 0;