diff --git a/package.json b/package.json
index c339c0585..beb1ab94a 100644
--- a/package.json
+++ b/package.json
@@ -11,7 +11,7 @@
         "pub": "node build/publish",
         "jest": "node build/jest",
         "start": "node --async-stack-traces --trace-deprecation --enable-source-maps build/start",
-        "clean": "zsh -c \"rm -r tsconfig.build.tsbuildinfo ./packages/*/tsconfig.tsbuildinfo ./packages/*/dist ./coverage\""
+        "clean": "zsh -c \"rm -r tsconfig.build.tsbuildinfo ./packages/*/tsconfig.tsbuildinfo ./packages/*/dist ./.coverage\""
     },
     "version": "1.0.0",
     "license": "AGPL-3.0-only",
diff --git a/packages/html2md/lib.ts b/packages/html2md/lib.ts
deleted file mode 100644
index a4cf55161..000000000
--- a/packages/html2md/lib.ts
+++ /dev/null
@@ -1,20 +0,0 @@
-import 'hydrooj';
-import TurndownService from 'turndown';
-
-declare module 'hydrooj' {
-    interface Lib {
-        convertHTML: (str: string) => string,
-    }
-}
-
-const turndownService = new TurndownService({
-    headingStyle: 'atx',
-    codeBlockStyle: 'fenced',
-    bulletListMarker: '-',
-});
-
-export function convertHTML(html: string) {
-    return turndownService.turndown(html);
-}
-
-global.Hydro.lib.convertHTML = convertHTML;
diff --git a/packages/html2md/package.json b/packages/html2md/package.json
deleted file mode 100644
index 7b60ab181..000000000
--- a/packages/html2md/package.json
+++ /dev/null
@@ -1,23 +0,0 @@
-{
-    "name": "@hydrooj/html2md",
-    "version": "1.0.2",
-    "description": "turn html into markdown",
-    "main": "lib.js",
-    "typings": "lib.d.ts",
-    "repository": "https://github.com/hydro-dev/Hydro.git",
-    "author": "undefined <masnn0@outlook.com>",
-    "license": "AGPL-3.0-only",
-    "dependencies": {
-        "turndown": "^6.0.0"
-    },
-    "devDependencies": {
-        "@types/turndown": "^5.0.0"
-    },
-    "peerDependencies": {
-        "hydrooj": "^2.12.22"
-    },
-    "scripts": {
-        "build": "tsc",
-        "lint": "eslint . --ext ts --fix"
-    }
-}
\ No newline at end of file
diff --git a/packages/html2md/test/lib.spec.ts b/packages/html2md/test/lib.spec.ts
deleted file mode 100644
index eb19eca43..000000000
--- a/packages/html2md/test/lib.spec.ts
+++ /dev/null
@@ -1,8 +0,0 @@
-import 'hydrooj';
-import { convertHTML } from '@hydrooj/html2md/lib';
-
-describe('html2md', () => {
-    test('convertHTML', () => {
-        expect(convertHTML('<h1>Test</h1><p>test</p>')).toStrictEqual('# Test\n\ntest');
-    });
-});
diff --git a/packages/html2md/tsconfig.json b/packages/html2md/tsconfig.json
deleted file mode 100644
index aa7d73857..000000000
--- a/packages/html2md/tsconfig.json
+++ /dev/null
@@ -1,19 +0,0 @@
-{
-    "compilerOptions": {
-        "target": "es2019",
-        "module": "commonjs",
-        "esModuleInterop": true,
-        "moduleResolution": "node",
-        "declaration": true,
-        "sourceMap": true,
-        "composite": true,
-        "strictBindCallApply": true,
-        "experimentalDecorators": true,
-        "outDir": ".",
-        "rootDir": "."
-    },
-    "include": [
-        "*.ts"
-    ],
-    "exclude": []
-}
\ No newline at end of file
diff --git a/packages/hydrooj/package.json b/packages/hydrooj/package.json
index 8b831a3be..fe2f88391 100644
--- a/packages/hydrooj/package.json
+++ b/packages/hydrooj/package.json
@@ -1,6 +1,6 @@
 {
     "name": "hydrooj",
-    "version": "2.13.9",
+    "version": "2.13.10",
     "bin": "bin/hydrooj.js",
     "main": "dist/loader.js",
     "typings": "dist/loader.d.ts",
diff --git a/packages/hydrooj/src/check.ts b/packages/hydrooj/src/check.ts
index c2e62047d..67ee9a8a8 100644
--- a/packages/hydrooj/src/check.ts
+++ b/packages/hydrooj/src/check.ts
@@ -43,7 +43,7 @@ const checks: Dictionary<CheckItem> = {
     },
 };
 
-export async function start(ctx, log, warn, error, cb: (id: string) => any) {
+export async function start(ctx, log, warn, error, cb: (id: string) => void) {
     const id = String.random(6);
     cb(id);
     for (const name in checks) {
diff --git a/packages/hydrooj/src/interface.ts b/packages/hydrooj/src/interface.ts
index a516c4a7c..df2efdd69 100644
--- a/packages/hydrooj/src/interface.ts
+++ b/packages/hydrooj/src/interface.ts
@@ -5,6 +5,10 @@ import { Dictionary, NumericDictionary } from 'lodash';
 
 export type NumberKeys<O> = {
     [K in keyof O]: number extends O[K] ? K : never
+}[keyof O];
+
+export type ArrayKeys<O, P = any> = {
+    [K in keyof O]: P[] extends O[K] ? K : never
 }[keyof O]
 
 export interface System {
@@ -157,7 +161,7 @@ export type ProblemConfig = LocalProblemConfig | RemoteProblemConfig;
 export interface Pdoc {
     _id: ObjectID,
     domainId: string,
-    docType: number,
+    docType: 10,
     docId: number,
     pid: string,
     owner: number,
@@ -181,14 +185,21 @@ export interface Pdoc {
 
 export type Pdict = NumericDictionary<Pdoc>;
 
-export interface ProblemStatusDoc {
+export interface StatusDoc {
     _id: ObjectID,
-    docId: number,
+    docId: any,
     docType: number,
     domainId: string,
     uid: number,
+}
+
+export interface ProblemStatusDoc extends StatusDoc {
+    docId: number,
+    docType: 10,
     rid?: ObjectID,
     status?: number,
+    nSubmit?: number,
+    nAccept?: number,
     star?: boolean,
 }
 
diff --git a/packages/hydrooj/src/model/blacklist.ts b/packages/hydrooj/src/model/blacklist.ts
index 54e69a49e..c6e3f4b22 100644
--- a/packages/hydrooj/src/model/blacklist.ts
+++ b/packages/hydrooj/src/model/blacklist.ts
@@ -1,9 +1,7 @@
-import { Collection } from 'mongodb';
 import * as db from '../service/db';
 import * as bus from '../service/bus';
-import { Bdoc } from '../interface';
 
-const coll: Collection<Bdoc> = db.collection('blacklist');
+const coll = db.collection('blacklist');
 
 export async function add(ip: string) {
     /**
diff --git a/packages/hydrooj/src/model/document.ts b/packages/hydrooj/src/model/document.ts
index 97a8f5d70..d31aa8f54 100644
--- a/packages/hydrooj/src/model/document.ts
+++ b/packages/hydrooj/src/model/document.ts
@@ -1,9 +1,11 @@
 import assert from 'assert';
-import { ObjectID, Cursor, FilterQuery } from 'mongodb';
+import {
+    ObjectID, Cursor, FilterQuery, UpdateQuery,
+} from 'mongodb';
 import * as db from '../service/db';
 import * as bus from '../service/bus';
 import {
-    Pdoc, Ddoc, Ufdoc, Drdoc, Tdoc, TrainingDoc, NumberKeys,
+    Pdoc, Ddoc, Ufdoc, Drdoc, Tdoc, TrainingDoc, NumberKeys, ArrayKeys, ProblemStatusDoc,
 } from '../interface';
 
 type DocID = ObjectID | string | number;
@@ -35,6 +37,11 @@ export interface DocType {
     [TYPE_HOMEWORK]: Tdoc,
 }
 
+export interface DocStatusType {
+    [TYPE_PROBLEM]: ProblemStatusDoc,
+    [key: number]: any
+}
+
 export async function add<T extends DocID, K extends keyof DocType>(
     domainId: string, content: string, owner: number,
     docType: K, docId: DocType[K]['docId'],
@@ -104,8 +111,8 @@ export function deleteMulti<K extends keyof DocType>(
     return coll.deleteMany({ ...query, domainId, docType });
 }
 
-export function deleteMultiStatus<K extends keyof DocType>(
-    domainId: string, docType: K, query?: FilterQuery<DocType[K]>,
+export function deleteMultiStatus<K extends keyof DocStatusType>(
+    domainId: string, docType: K, query?: FilterQuery<DocStatusType[K]>,
 ) {
     return collStatus.deleteMany({ ...query, domainId, docType });
 }
@@ -128,8 +135,6 @@ export async function inc<K extends keyof DocType>(
     return res.value;
 }
 
-type Q = NumberKeys<DocType[10]>
-
 export async function incAndSet<K extends keyof DocType>(
     domainId: string, docType: K, docId: DocType[K]['docId'],
     key: NumberKeys<DocType[K]>, value: number, args: Partial<DocType[K]>,
@@ -169,7 +174,7 @@ export async function push<K extends keyof DocType, T extends keyof DocType[K]>(
 
 export async function pull<K extends keyof DocType>(
     domainId: string, docType: K, docId: DocType[K]['docId'],
-    setKey: string, contents: string[],
+    setKey: ArrayKeys<DocType[K]>, contents: string[],
 ): Promise<DocType[K]> {
     const res = await coll.findOneAndUpdate(
         { domainId, docType, docId },
@@ -179,10 +184,10 @@ export async function pull<K extends keyof DocType>(
     return res.value;
 }
 
-export async function deleteSub(
-    domainId: string, docType: number, docId: DocID,
-    key: string, subId: ObjectID,
-) {
+export async function deleteSub<K extends keyof DocType>(
+    domainId: string, docType: K, docId: DocType[K]['docId'],
+    key: ArrayKeys<DocType[K]>, subId: ObjectID,
+): Promise<DocType[K]> {
     const res = await coll.findOneAndUpdate(
         { domainId, docType, docId },
         { $pull: { [key]: { _id: subId } } },
@@ -191,10 +196,10 @@ export async function deleteSub(
     return res.value;
 }
 
-export async function getSub(
-    domainId: string, docType: number, docId: DocID,
-    key: string, subId: ObjectID,
-) {
+export async function getSub<T extends keyof DocType, K extends ArrayKeys<DocType[T]>>(
+    domainId: string, docType: T, docId: DocType[T]['docId'],
+    key: K, subId: ObjectID,
+): Promise<[DocType[T], DocType[T][K]][0]> {
     const doc = await coll.findOne({
         domainId,
         docType,
@@ -208,10 +213,10 @@ export async function getSub(
     return [doc, null];
 }
 
-export async function setSub(
-    domainId: string, docType: number, docId: DocID,
-    key: string, subId: ObjectID, args: any,
-) {
+export async function setSub<T extends keyof DocType, K extends ArrayKeys<DocType[T]>>(
+    domainId: string, docType: T, docId: DocType[T]['docId'],
+    key: K, subId: ObjectID, args: UpdateQuery<DocType[T][K][0]>['$set'],
+): Promise<DocType[T]> {
     const $set = {};
     for (const k in args) {
         $set[`${key}.$.${k}`] = args[k];
@@ -229,9 +234,9 @@ export async function setSub(
     return res.value;
 }
 
-export async function addToSet(
-    domainId: string, docType: number, docId: DocID,
-    setKey: string, content: string,
+export async function addToSet<T extends keyof DocType, K extends ArrayKeys<DocType[T], string>>(
+    domainId: string, docType: T, docId: DocType[T]['docId'],
+    setKey: K, content: string,
 ) {
     const res = await coll.findOneAndUpdate(
         { domainId, docType, docId },
@@ -241,23 +246,29 @@ export async function addToSet(
     return res.value;
 }
 
-export function getStatus(domainId: string, docType: number, docId: DocID, uid: number) {
+export function getStatus<K extends keyof DocStatusType>(
+    domainId: string, docType: K, docId: DocStatusType[K]['docId'], uid: number,
+): Promise<DocStatusType[K]> {
     return collStatus.findOne({
         domainId, docType, docId, uid,
     });
 }
 
-export function getMultiStatus(domainId: string, docType: number, args: any) {
+export function getMultiStatus<K extends keyof DocStatusType>(
+    domainId: string, docType: K, args: FilterQuery<DocStatusType[K]>,
+): Cursor<DocStatusType[K]> {
     return collStatus.find({ ...args, docType, domainId });
 }
 
-export function getMultiStatusWithoutDomain(docType: number, args: any) {
+export function getMultiStatusWithoutDomain<K extends keyof DocStatusType>(
+    docType: K, args: FilterQuery<DocStatusType[K]>,
+): Cursor<DocStatusType[K]> {
     return collStatus.find({ ...args, docType });
 }
 
-export async function setStatus(
-    domainId: string, docType: number, docId: DocID, uid: number, args: any,
-) {
+export async function setStatus<K extends keyof DocStatusType>(
+    domainId: string, docType: K, docId: DocStatusType[K]['docId'], uid: number, args: UpdateQuery<DocStatusType[K]>['$set'],
+): Promise<DocStatusType[K]> {
     const res = await collStatus.findOneAndUpdate(
         {
             domainId, docType, docId, uid,
@@ -268,7 +279,9 @@ export async function setStatus(
     return res.value;
 }
 
-export function setMultiStatus(domainId: string, docType: number, query: any, args: any) {
+export function setMultiStatus<K extends keyof DocStatusType>(
+    domainId: string, docType: K, query: FilterQuery<DocStatusType[K]>, args: UpdateQuery<DocStatusType[K]>['$set'],
+) {
     return collStatus.updateMany(
         { domainId, docType, ...query },
         { $set: args },
diff --git a/tsconfig.json b/tsconfig.json
index 1ee9215de..2b60c7dc7 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -14,7 +14,6 @@
         { "path": "packages/hydrooj" },
         { "path": "packages/hydrojudge" },
         { "path": "packages/geoip" },
-        { "path": "packages/html2md" },
         { "path": "packages/better-search" },
         { "path": "packages/fps-importer" },
         { "path": "packages/login-with-github" },