diff --git a/packages/redux-devtools-core/.eslintrc.js b/packages/redux-devtools-core/.eslintrc.js
index f1079770..ce28cd35 100644
--- a/packages/redux-devtools-core/.eslintrc.js
+++ b/packages/redux-devtools-core/.eslintrc.js
@@ -18,7 +18,7 @@ module.exports = {
       },
     },
     {
-      files: ['webpack.config.umd.ts'],
+      files: ['webpack.config.ts', 'webpack.config.umd.ts'],
       extends: '../../eslintrc.ts.base.json',
       parserOptions: {
         tsconfigRootDir: __dirname,
diff --git a/packages/redux-devtools-core/src/app/actions/index.ts b/packages/redux-devtools-core/src/app/actions/index.ts
index ac79a39a..10617a12 100644
--- a/packages/redux-devtools-core/src/app/actions/index.ts
+++ b/packages/redux-devtools-core/src/app/actions/index.ts
@@ -502,7 +502,7 @@ export interface EmitAction {
 
 interface ListRequest {
   type: 'list';
-  data: Data;
+  data: Data[];
 }
 interface AddRequest {
   type: 'add';
@@ -513,7 +513,7 @@ interface RemoveRequest {
   data: Data;
   id: unknown;
 }
-type UpdateReportsRequest = ListRequest | AddRequest | RemoveRequest;
+export type UpdateReportsRequest = ListRequest | AddRequest | RemoveRequest;
 interface UpdateReportsAction {
   type: typeof UPDATE_REPORTS;
   request: UpdateReportsRequest;
diff --git a/packages/redux-devtools-core/src/app/components/InstanceSelector.tsx b/packages/redux-devtools-core/src/app/components/InstanceSelector.tsx
index a6bb864f..debe8524 100644
--- a/packages/redux-devtools-core/src/app/components/InstanceSelector.tsx
+++ b/packages/redux-devtools-core/src/app/components/InstanceSelector.tsx
@@ -1,5 +1,4 @@
 import React, { Component } from 'react';
-import PropTypes from 'prop-types';
 import { connect, ResolveThunks } from 'react-redux';
 import { Select } from 'devui';
 import { selectInstance } from '../actions';
@@ -10,12 +9,6 @@ type DispatchProps = ResolveThunks<typeof actionCreators>;
 type Props = StateProps & DispatchProps;
 
 class InstanceSelector extends Component<Props> {
-  static propTypes = {
-    selected: PropTypes.string,
-    instances: PropTypes.object.isRequired,
-    onSelect: PropTypes.func.isRequired,
-  };
-
   select?: { readonly value: string; readonly label: string }[];
 
   render() {
@@ -24,8 +17,7 @@ class InstanceSelector extends Component<Props> {
     let name;
     Object.keys(instances).forEach((key) => {
       name = instances[key].name;
-      if (name !== undefined)
-        this.select!.push({ value: key, label: instances[key].name });
+      if (name !== undefined) this.select!.push({ value: key, label: name });
     });
 
     return (
diff --git a/packages/redux-devtools-core/src/app/components/Settings/index.tsx b/packages/redux-devtools-core/src/app/components/Settings/index.tsx
index ff562ae2..ae18464a 100644
--- a/packages/redux-devtools-core/src/app/components/Settings/index.tsx
+++ b/packages/redux-devtools-core/src/app/components/Settings/index.tsx
@@ -23,8 +23,7 @@ class Settings extends Component<{}, State> {
     return (
       // eslint-disable-next-line @typescript-eslint/ban-types
       <Tabs<{}>
-        toRight
-        tabs={this.tabs}
+        tabs={this.tabs as any}
         selected={this.state.selected}
         onClick={this.handleSelect}
       />
diff --git a/packages/redux-devtools-core/src/app/components/buttons/PersistButton.tsx b/packages/redux-devtools-core/src/app/components/buttons/PersistButton.tsx
index 7ae77e47..e78349a5 100644
--- a/packages/redux-devtools-core/src/app/components/buttons/PersistButton.tsx
+++ b/packages/redux-devtools-core/src/app/components/buttons/PersistButton.tsx
@@ -21,7 +21,6 @@ class LockButton extends Component<Props> {
   render() {
     return (
       <Button
-        toolbar
         tooltipPosition="bottom"
         disabled={this.props.disabled}
         mark={this.props.persisted && 'base0D'}
diff --git a/packages/redux-devtools-core/src/app/middlewares/api.ts b/packages/redux-devtools-core/src/app/middlewares/api.ts
index 08f91ef3..bc303987 100644
--- a/packages/redux-devtools-core/src/app/middlewares/api.ts
+++ b/packages/redux-devtools-core/src/app/middlewares/api.ts
@@ -21,6 +21,7 @@ import {
   LiftedActionAction,
   Request,
   DispatchAction,
+  UpdateReportsRequest,
 } from '../actions';
 import { nonReduxDispatch } from '../utils/monitorActions';
 import { StoreState } from '../reducers';
@@ -136,7 +137,7 @@ function subscribe(
   const channel = socket.subscribe(channelName);
   if (subscription === UPDATE_STATE) channel.watch(monitoring);
   else {
-    const watcher = (request: Request) => {
+    const watcher = (request: UpdateReportsRequest) => {
       store.dispatch({ type: subscription, request });
     };
     channel.watch(watcher);
diff --git a/packages/redux-devtools-core/src/app/reducers/instances.ts b/packages/redux-devtools-core/src/app/reducers/instances.ts
index 0e17daea..aa98f2c3 100644
--- a/packages/redux-devtools-core/src/app/reducers/instances.ts
+++ b/packages/redux-devtools-core/src/app/reducers/instances.ts
@@ -107,13 +107,14 @@ function updateState(
 
   let newState;
   const liftedState = state[id] || state.default;
-  const action = (request.action && parseJSON(request.action, serialize)) || {};
+  const action = ((request.action && parseJSON(request.action, serialize)) ||
+    {}) as PerformAction<Action<unknown>>;
 
   switch (request.type) {
     case 'INIT':
       newState = recompute(state.default, payload, {
         action: { type: '@@INIT' },
-        timestamp: (action as { timestamp?: unknown }).timestamp || Date.now(),
+        timestamp: (action as { timestamp?: number }).timestamp || Date.now(),
       });
       break;
     case 'ACTION': {
@@ -301,7 +302,10 @@ function init(
   };
 }
 
-export default function instances(state = initialState, action: StoreAction) {
+export default function instances(
+  state = initialState,
+  action: StoreAction
+): InstancesState {
   switch (action.type) {
     case UPDATE_STATE: {
       const { request } = action;
@@ -360,7 +364,7 @@ export default function instances(state = initialState, action: StoreAction) {
             ...state,
             states: {
               ...state.states,
-              [id]: parseJSON(action.state),
+              [id]: parseJSON(action.state) as State,
             },
           };
         }
diff --git a/packages/redux-devtools-core/src/app/reducers/reports.ts b/packages/redux-devtools-core/src/app/reducers/reports.ts
index 66d9f6f1..a085461c 100644
--- a/packages/redux-devtools-core/src/app/reducers/reports.ts
+++ b/packages/redux-devtools-core/src/app/reducers/reports.ts
@@ -15,7 +15,10 @@ const initialState: ReportsState = {
   data: [],
 };
 
-export default function reports(state = initialState, action: StoreAction) {
+export default function reports(
+  state = initialState,
+  action: StoreAction
+): ReportsState {
   /* if (action.type === GET_REPORT_SUCCESS) {
     const id = action.data.id;
     return {
@@ -28,17 +31,16 @@ export default function reports(state = initialState, action: StoreAction) {
     return state;
 
   const request = action.request;
-  const data = request.data;
   switch (request.type) {
     case 'list':
       return {
         ...state,
-        data,
+        data: request.data,
       };
     case 'add':
       return {
         ...state,
-        data: [...state.data, data],
+        data: [...state.data, request.data],
       };
     case 'remove':
       return {
diff --git a/packages/redux-devtools-core/src/app/utils/stringifyJSON.ts b/packages/redux-devtools-core/src/app/utils/stringifyJSON.ts
index 3765284c..403e621e 100644
--- a/packages/redux-devtools-core/src/app/utils/stringifyJSON.ts
+++ b/packages/redux-devtools-core/src/app/utils/stringifyJSON.ts
@@ -14,7 +14,10 @@ function replacer(key: string, value: unknown) {
   return value;
 }
 
-export default function stringifyJSON(data: unknown, serialize: boolean) {
+export default function stringifyJSON(
+  data: unknown,
+  serialize: boolean | undefined
+) {
   return serialize
     ? jsan.stringify(data, replacer, (null as unknown) as undefined, true)
     : jsan.stringify(data);
diff --git a/packages/redux-devtools-core/src/app/utils/updateState.ts b/packages/redux-devtools-core/src/app/utils/updateState.ts
index c2b35bcf..eb2ba394 100644
--- a/packages/redux-devtools-core/src/app/utils/updateState.ts
+++ b/packages/redux-devtools-core/src/app/utils/updateState.ts
@@ -6,7 +6,9 @@ import { PerformAction } from 'redux-devtools-instrument';
 export function recompute(
   previousLiftedState: State,
   storeState: State,
-  action: Action<unknown>,
+  action:
+    | PerformAction<Action<unknown>>
+    | { action: Action<unknown>; timestamp?: number; stack?: string },
   nextActionId = 1,
   maxAge?: number,
   isExcess?: boolean
@@ -22,15 +24,15 @@ export function recompute(
   }
   liftedState.stagedActionIds = [...liftedState.stagedActionIds, actionId];
   liftedState.actionsById = { ...liftedState.actionsById };
-  if (action.type === 'PERFORM_ACTION') {
+  if ((action as PerformAction<Action<unknown>>).type === 'PERFORM_ACTION') {
     liftedState.actionsById[actionId] = action as PerformAction<
       Action<unknown>
     >;
   } else {
     liftedState.actionsById[actionId] = {
-      action: (action as any).action || action,
-      timestamp: (action as any).timestamp || Date.now(),
-      stack: (action as any).stack,
+      action: action.action || action,
+      timestamp: action.timestamp || Date.now(),
+      stack: action.stack,
       type: 'PERFORM_ACTION',
     };
   }
diff --git a/packages/redux-devtools-core/webpack.config.ts b/packages/redux-devtools-core/webpack.config.ts
index ed75e5f7..342b9751 100644
--- a/packages/redux-devtools-core/webpack.config.ts
+++ b/packages/redux-devtools-core/webpack.config.ts
@@ -1,14 +1,15 @@
-const path = require('path');
-const webpack = require('webpack');
-const HtmlWebpackPlugin = require('html-webpack-plugin');
+import * as path from 'path';
+import * as webpack from 'webpack';
+import HtmlWebpackPlugin from 'html-webpack-plugin';
+import ForkTsCheckerWebpackPlugin from 'fork-ts-checker-webpack-plugin';
 
-module.exports = (env = {}) => ({
+module.exports = (env: { development?: boolean; platform?: string } = {}) => ({
   mode: env.development ? 'development' : 'production',
   entry: {
-    app: './index.js',
+    app: './index',
   },
   output: {
-    path: path.resolve(__dirname, 'build/' + env.platform),
+    path: path.resolve(__dirname, `build/${env.platform as string}`),
     publicPath: '',
     filename: 'js/[name].js',
     sourceMapFilename: 'js/[name].map',
@@ -16,7 +17,7 @@ module.exports = (env = {}) => ({
   module: {
     rules: [
       {
-        test: /\.js$/,
+        test: /\.(js|ts)x?$/,
         loader: 'babel-loader',
         exclude: /node_modules/,
       },
@@ -44,6 +45,9 @@ module.exports = (env = {}) => ({
       },
     ],
   },
+  resolve: {
+    extensions: ['.js', '.jsx', '.ts', '.tsx'],
+  },
   plugins: [
     new webpack.DefinePlugin({
       'process.env': {
@@ -56,6 +60,11 @@ module.exports = (env = {}) => ({
     new HtmlWebpackPlugin({
       template: 'assets/index.html',
     }),
+    new ForkTsCheckerWebpackPlugin({
+      typescript: {
+        configFile: 'tsconfig.json',
+      },
+    }),
   ],
   optimization: {
     minimize: false,