diff --git a/docs/concepts/11-typescript.md b/docs/concepts/11-typescript.md
index 74fcb2f6a..2408498dc 100644
--- a/docs/concepts/11-typescript.md
+++ b/docs/concepts/11-typescript.md
@@ -11,10 +11,12 @@ To define a custom `Element` or `Text` type, extend the `CustomTypes` interface
 ```ts
 import { Descendant } from 'slate'
 
+type CustomText = { text: string; bold: boolean; italic: boolean }
+
 declare module 'slate' {
   interface CustomTypes {
-    Element: { type: 'paragraph'; children: Descendant[] }
-    Text: { text: string; bold: boolean; italic: boolean }
+    Element: { type: 'paragraph'; children: CustomText[] }
+    Text: CustomText
   }
 }
 ```