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docs/src/docPages/guide/custom-extensions.md

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+# Custom extensions
+
+## toc
+
+## Introduction
+You can build your own extensions from scratch with the `Node`, `Mark`, and `Extension` classes. Just pass an object with your configuration and custom code. Read the [ovewrite & extend](/guide/extend-extensions) guide to learn more about all the things you can control.
+
+And if everything is working fine, don’t forget to [share it with the community](https://github.com/ueberdosis/tiptap/issues/819).
+
+### Create a node
+
+```js
+import { Node } from '@tiptap/core'
+
+const CustomNode = Node.create({
+  // Your code goes here.
+})
+```
+
+### Create a mark
+```js
+import { Mark } from '@tiptap/core'
+
+const CustomMark = Mark.create({
+  // Your code goes here.
+})
+```
+
+### Create an extension
+```js
+import { Extension } from '@tiptap/core'
+
+const CustomExtension = Extension.create({
+  // Your code goes here.
+})
+```