diff --git a/client/src/components/base.js b/client/src/components/base.tsx
similarity index 78%
rename from client/src/components/base.js
rename to client/src/components/base.tsx
index 0e7da78..511204f 100644
--- a/client/src/components/base.js
+++ b/client/src/components/base.tsx
@@ -1,12 +1,18 @@
 import {Component} from 'react';
 import log from '../utils/log';
 
-export default class Base extends Component {
+interface Apis {
+    [key: string]: any;
+}
+
+export default class Base<Props, States> extends Component<Props, States> {
+    private apis: Apis = {};
+
     async componentWillUnmount() {
         await this.clearDisposers();
     }
 
-    async registerApi(apis) {
+    async registerApi(apis: Apis) {
         if (!this.apis) this.apis = {};
 
         for (const [name, api] of Object.entries(apis)) {
@@ -22,7 +28,7 @@ export default class Base extends Component {
         }
     }
 
-    async clearDisposer(name) {
+    async clearDisposer(name: string) {
         if (!this.apis || !this.apis[name]) return;
 
         const item = this.apis[name];