diff --git a/.eslintrc b/.eslintrc
index 4e03bc478e..52d68ca1da 100644
--- a/.eslintrc
+++ b/.eslintrc
@@ -5,7 +5,12 @@
     "prettier/@typescript-eslint",
     "prettier/react"
   ],
-  "plugins": ["@typescript-eslint", "import", "react", "prettier"],
+  "plugins": [
+    "@typescript-eslint",
+    "import",
+    "react",
+    "prettier"
+  ],
   "parser": "@typescript-eslint/parser",
   "parserOptions": {
     "sourceType": "module",
@@ -16,7 +21,12 @@
   },
   "ignorePatterns": ["**/next-env.d.ts"],
   "settings": {
-    "import/extensions": [".js", ".ts", ".jsx", ".tsx"],
+    "import/extensions": [
+      ".js",
+      ".ts",
+      ".jsx",
+      ".tsx"
+    ],
     "react": {
       "version": "detect"
     }
@@ -29,8 +39,16 @@
   },
   "rules": {
     "constructor-super": "error",
-    "dot-notation": ["error", { "allowKeywords": true }],
-    "eqeqeq": ["error", "smart"],
+    "dot-notation": [
+      "error",
+      {
+        "allowKeywords": true
+      }
+    ],
+    "eqeqeq": [
+      "error",
+      "smart"
+    ],
     "import/default": "error",
     "import/export": "error",
     "import/first": "error",
@@ -40,7 +58,9 @@
     "import/no-deprecated": "error",
     "import/no-extraneous-dependencies": [
       "error",
-      { "peerDependencies": true }
+      {
+        "peerDependencies": true
+      }
     ],
     "import/no-mutable-exports": "error",
     "import/no-named-as-default": "error",
@@ -86,18 +106,27 @@
     "no-var": "error",
     "no-void": "error",
     "no-with": "error",
-    "object-shorthand": ["error", "always"],
+    "object-shorthand": [
+      "error",
+      "always"
+    ],
     "prefer-arrow-callback": "error",
     "prefer-const": [
       "error",
-      { "destructuring": "all", "ignoreReadBeforeAssign": true }
+      {
+        "destructuring": "all",
+        "ignoreReadBeforeAssign": true
+      }
     ],
     "prefer-rest-params": "error",
     "prefer-spread": "error",
     "prefer-template": "error",
     "prettier/prettier": "error",
     "radix": "error",
-    "react/jsx-boolean-value": ["error", "never"],
+    "react/jsx-boolean-value": [
+      "error",
+      "never"
+    ],
     "react/jsx-no-duplicate-props": "error",
     "react/jsx-no-target-blank": "error",
     "react/jsx-no-undef": "error",
@@ -112,15 +141,34 @@
     "react/react-in-jsx-scope": "error",
     "react/self-closing-comp": "error",
     "react/sort-prop-types": "error",
-    "spaced-comment": ["error", "always", { "exceptions": ["-"] }],
+    "spaced-comment": [
+      "error",
+      "always",
+      {
+        "exceptions": [
+          "-"
+        ]
+      }
+    ],
     "use-isnan": "error",
     "valid-jsdoc": [
       "error",
-      { "prefer": { "return": "returns" }, "requireReturn": false }
+      {
+        "prefer": {
+          "return": "returns"
+        },
+        "requireReturn": false
+      }
     ],
     "valid-typeof": "error",
-    "yield-star-spacing": ["error", "after"],
-    "yoda": ["error", "never"]
+    "yield-star-spacing": [
+      "error",
+      "after"
+    ],
+    "yoda": [
+      "error",
+      "never"
+    ]
   },
   "overrides": [
     {
@@ -131,4 +179,4 @@
       }
     }
   ]
-}
+}
\ No newline at end of file
diff --git a/docs/api/locations.md b/docs/api/locations.md
index e7758925a7..49bdd72b54 100644
--- a/docs/api/locations.md
+++ b/docs/api/locations.md
@@ -1,6 +1,6 @@
 # Location
 
-The `Location` interface is a union of the ways to refer to a specific location in a Slate document: paths, points or ranges. Methods will often accept a `Location` instead of requiring only a `Path`, `Point` or `Range`. 
+The `Location` interface is a union of the ways to refer to a specific location in a Slate document: paths, points or ranges. Methods will often accept a `Location` instead of requiring only a `Path`, `Point` or `Range`.
 
 ```typescript
 type Location = Path | Point | Range
@@ -26,9 +26,9 @@ type Path = number[]
 
 ```typescript
 interface Point {
-    path: Path
-    offset: number  
-    [key: string]: unknown
+  path: Path
+  offset: number
+  [key: string]: unknown
 }
 ```
 
@@ -66,9 +66,9 @@ Options: `{affinity?: 'forward' | 'backward' | null}`
 
 ```typescript
 interface Range {
-    anchor: Point
-    focus: Point
-    [key: string]: unknown
+  anchor: Point
+  focus: Point
+  [key: string]: unknown
 }
 ```
 
@@ -96,7 +96,7 @@ Get the intersection of one `range` with `another`.
 
 ###### `Range.isBackward(range: Range): boolean`
 
-Check if a `range` is backward, meaning that its anchor point appears *after* its focus point in the document.
+Check if a `range` is backward, meaning that its anchor point appears _after_ its focus point in the document.
 
 ###### `Range.isCollapsed(range: Range): boolean`
 
@@ -126,5 +126,4 @@ Get the start point of a `range`
 
 Transform a `range` by an `op`.
 
-Options: `{affinity: 'forward' | 'backward' | 
-'outward' | 'inward' | null}`
+Options: `{affinity: 'forward' | 'backward' | 'outward' | 'inward' | null}`
diff --git a/docs/api/nodes.md b/docs/api/nodes.md
index b3b9b3e489..6d8881ac55 100644
--- a/docs/api/nodes.md
+++ b/docs/api/nodes.md
@@ -1,6 +1,6 @@
 # Node
 
-The `Node` union type represents all of the different types of nodes that occur in a Slate document tree. 
+The `Node` union type represents all of the different types of nodes that occur in a Slate document tree.
 
 ```typescript
 type Node = Editor | Element | Text
@@ -57,7 +57,7 @@ Get the first node entry in a root node from a `path`.
 
 ###### `Node.fragment(root: Node, range: Range): Descendant[]`
 
-Get the sliced fragment represented by the  `range`.
+Get the sliced fragment represented by the `range`.
 
 ###### `Node.get(root: Node, path: Path): Node`
 
@@ -85,7 +85,7 @@ Get the node at a specific `path`, ensuring it's a leaf text node. If the node i
 
 ###### `Node.levels(root: Node, path: Path, options?): Generator<NodeEntry>`
 
-Return a generator of the nodes in a branch of the tree, from a specific `path`.  By default, the order is top-down, from the lowest to the highest node in the tree, but you can pass the `reverse: true` option to go bottom-up.
+Return a generator of the nodes in a branch of the tree, from a specific `path`. By default, the order is top-down, from the lowest to the highest node in the tree, but you can pass the `reverse: true` option to go bottom-up.
 
 Options: `{reverse?: boolean}`
 
@@ -236,8 +236,8 @@ Check if an element matches a set of `props`. Note: This checks custom propertie
 
 ```typescript
 interface Text {
-    text: string,
-    [key: string]: unknown
+  text: string
+  [key: string]: unknown
 }
 ```
 
diff --git a/docs/api/refs.md b/docs/api/refs.md
index 84c6cd6fd6..1f9332d46b 100644
--- a/docs/api/refs.md
+++ b/docs/api/refs.md
@@ -8,9 +8,9 @@
 
 ```typescript
 interface PointRef {
-    current: Point | null
-    affinity: 'forward' | 'backward' | null
-    unref(): Point | null
+  current: Point | null
+  affinity: 'forward' | 'backward' | null
+  unref(): Point | null
 }
 ```
 
@@ -26,9 +26,9 @@ Transform the point refs current value by an `op`.
 
 ```typescript
 interface RangeRef {
-    current: Range | null
-    affinity: 'forward' | 'backward' | 'outward' | 'inward' | null
-    unref(): Range | null
+  current: Range | null
+  affinity: 'forward' | 'backward' | 'outward' | 'inward' | null
+  unref(): Range | null
 }
 ```
 
diff --git a/docs/api/transforms.md b/docs/api/transforms.md
index aee4cf74e5..34308a050b 100644
--- a/docs/api/transforms.md
+++ b/docs/api/transforms.md
@@ -8,28 +8,28 @@ Transforms that operate on nodes.
 
 ###### NodeOptions
 
-All transforms listed below support a parameter `options`. This includes options specific to the transform, and general `NodeOptions` to specify the place in the document that the transform is applied to. 
+All transforms listed below support a parameter `options`. This includes options specific to the transform, and general `NodeOptions` to specify the place in the document that the transform is applied to.
 
 ```typescript
 interface NodeOptions {
-    at?: Location
-    match?: (node: Node) => boolean
-    mode?: 'highest' | 'lowest'
-    voids?: boolean
+  at?: Location
+  match?: (node: Node) => boolean
+  mode?: 'highest' | 'lowest'
+  voids?: boolean
 }
 ```
 
 ###### `Transforms.insertNodes(editor: Editor, nodes: Node | Node[], options?)`
 
-Insert `nodes` at the specified location in the document.  If no location is specified, insert at the current selection. If there is no selection, insert at the end of the document.
+Insert `nodes` at the specified location in the document. If no location is specified, insert at the current selection. If there is no selection, insert at the end of the document.
 
-Options supported: `NodeOptions & {hanging?: boolean, select?: boolean}`. 
+Options supported: `NodeOptions & {hanging?: boolean, select?: boolean}`.
 
 ###### `Transforms.removeNodes(editor: Editor, options?)`
 
-Remove nodes at the specified location in the document. If no location is specified, remove the nodes in the selection. 
+Remove nodes at the specified location in the document. If no location is specified, remove the nodes in the selection.
 
-Options supported: `NodeOptions & {hanging?: boolean}` 
+Options supported: `NodeOptions & {hanging?: boolean}`
 
 ###### `Transforms.mergeNodes(editor: Editor, options?)`
 
@@ -41,7 +41,7 @@ Options supported: `NodeOptions & {hanging?: boolean}`
 
 Split nodes at the specified location. If no location is specified, split the selection.
 
-Options supported: `NodeOptions & {height?: number, always?: boolean}` 
+Options supported: `NodeOptions & {height?: number, always?: boolean}`
 
 ###### `Transforms.wrapNodes(editor: Editor, element: Element, options?)`
 
@@ -75,7 +75,7 @@ Options supported: `NodeOptions`. For `options.mode`, `'all'` is also supported.
 
 ###### `Transforms.moveNodes(editor: Editor, options)`
 
-Move the nodes from an origin to a destination. A destination must be specified in the `options`.  If no origin is specified, move the selection.
+Move the nodes from an origin to a destination. A destination must be specified in the `options`. If no origin is specified, move the selection.
 
 Options supported: `NodeOptions & {to: Path}`. For `options.mode`, `'all'` is also supported.
 
@@ -87,7 +87,7 @@ Transforms that operate on the document's selection.
 
 Collapse the selection to a single point.
 
-Options:  `{edge?: 'anchor' | 'focus' | 'start' | 'end'}`
+Options: `{edge?: 'anchor' | 'focus' | 'start' | 'end'}`
 
 ###### `Transforms.select(editor: Editor, target: Location)`
 
diff --git a/docs/libraries/slate-hyperscript.md b/docs/libraries/slate-hyperscript.md
index db81fb0f6e..4a7afbb98b 100644
--- a/docs/libraries/slate-hyperscript.md
+++ b/docs/libraries/slate-hyperscript.md
@@ -1,3 +1,3 @@
 # Slate Hyperscript
 
-This package contains a hyperscript helper for creating Slate documents with JSX!
\ No newline at end of file
+This package contains a hyperscript helper for creating Slate documents with JSX!
diff --git a/docs/libraries/slate-react.md b/docs/libraries/slate-react.md
index 1fc56c056c..537aa79b24 100644
--- a/docs/libraries/slate-react.md
+++ b/docs/libraries/slate-react.md
@@ -18,11 +18,11 @@ React components for rendering Slate editors
 
 The main Slate editor.
 
-###### `DefaultElement(props: RenderElementProps)` 
+###### `DefaultElement(props: RenderElementProps)`
 
 The default element renderer.
 
-###### `DefaultLeaf(props: RenderLeafProps)` 
+###### `DefaultLeaf(props: RenderLeafProps)`
 
 The default custom leaf renderer.
 
@@ -137,4 +137,3 @@ Adds React and DOM specific behaviors to the editor.
 ## Utils
 
 Private convenience modules
-
diff --git a/docs/walkthroughs/01-installing-slate.md b/docs/walkthroughs/01-installing-slate.md
index 9ed264f0e8..3471fe895f 100644
--- a/docs/walkthroughs/01-installing-slate.md
+++ b/docs/walkthroughs/01-installing-slate.md
@@ -16,10 +16,9 @@ _Note, if you'd rather use a pre-bundled version of Slate, you can `yarn add sla
 
 Once you've installed Slate, you'll need to import it.
 
-
 ```jsx
 // Import React dependencies.
-import React, { useEffect, useMemo, useState } from "react";
+import React, { useEffect, useMemo, useState } from 'react'
 // Import the Slate editor factory.
 import { createEditor } from 'slate'
 
@@ -70,7 +69,11 @@ const App = () => {
   const [value, setValue] = useState([])
   // Render the Slate context.
   return (
-    <Slate editor={editor} value={value} onChange={newValue => setValue(newValue)} />
+    <Slate
+      editor={editor}
+      value={value}
+      onChange={newValue => setValue(newValue)}
+    />
   )
 }
 ```
@@ -89,7 +92,11 @@ const App = () => {
   const [value, setValue] = useState([])
   return (
     // Add the editable component inside the context.
-    <Slate editor={editor} value={value} onChange={newValue => setValue(newValue)}>
+    <Slate
+      editor={editor}
+      value={value}
+      onChange={newValue => setValue(newValue)}
+    >
       <Editable />
     </Slate>
   )
@@ -114,7 +121,11 @@ const App = () => {
   ])
 
   return (
-    <Slate editor={editor} value={value} onChange={newValue => setValue(newValue)}>
+    <Slate
+      editor={editor}
+      value={value}
+      onChange={newValue => setValue(newValue)}
+    >
       <Editable />
     </Slate>
   )
diff --git a/docs/walkthroughs/02-adding-event-handlers.md b/docs/walkthroughs/02-adding-event-handlers.md
index d3078cc47a..00246ac8bd 100644
--- a/docs/walkthroughs/02-adding-event-handlers.md
+++ b/docs/walkthroughs/02-adding-event-handlers.md
@@ -75,7 +75,7 @@ const App = () => {
             // Prevent the ampersand character from being inserted.
             event.preventDefault()
             // Execute the `insertText` method when the event occurs.
-            editor.insertText("and")
+            editor.insertText('and')
           }
         }}
       />
diff --git a/docs/walkthroughs/03-defining-custom-elements.md b/docs/walkthroughs/03-defining-custom-elements.md
index 05848397f7..8db481832e 100644
--- a/docs/walkthroughs/03-defining-custom-elements.md
+++ b/docs/walkthroughs/03-defining-custom-elements.md
@@ -22,7 +22,7 @@ const App = () => {
         onKeyDown={event => {
           if (event.key === '&') {
             event.preventDefault()
-            editor.insertText("and")
+            editor.insertText('and')
           }
         }}
       />
@@ -93,7 +93,7 @@ const App = () => {
         onKeyDown={event => {
           if (event.key === '&') {
             event.preventDefault()
-            editor.insertText("and")
+            editor.insertText('and')
           }
         }}
       />
diff --git a/package.json b/package.json
index 719843dc3e..2419ad33c3 100644
--- a/package.json
+++ b/package.json
@@ -88,4 +88,4 @@
     "source-map-loader": "^0.2.4",
     "typescript": "^3.7.2"
   }
-}
+}
\ No newline at end of file
diff --git a/packages/slate-history/src/history-editor.ts b/packages/slate-history/src/history-editor.ts
index 28f9f2e7dc..8342d291c3 100644
--- a/packages/slate-history/src/history-editor.ts
+++ b/packages/slate-history/src/history-editor.ts
@@ -13,7 +13,7 @@ export const MERGING = new WeakMap<Editor, boolean | undefined>()
  * `HistoryEditor` contains helpers for history-enabled editors.
  */
 
-export interface HistoryEditor extends Editor {
+export type HistoryEditor = Editor & {
   history: History
   undo: () => void
   redo: () => void
@@ -25,7 +25,7 @@ export const HistoryEditor = {
    */
 
   isHistoryEditor(value: any): value is HistoryEditor {
-    return Editor.isEditor(value) && History.isHistory(value.history)
+    return History.isHistory(value.history) && Editor.isEditor(value)
   },
 
   /**
diff --git a/packages/slate-history/test/jsx.d.ts b/packages/slate-history/test/jsx.d.ts
new file mode 100644
index 0000000000..de69552d4c
--- /dev/null
+++ b/packages/slate-history/test/jsx.d.ts
@@ -0,0 +1,6 @@
+// This allows tests to include Slate Nodes written in JSX without TypeScript complaining.
+declare namespace jsx.JSX {
+  interface IntrinsicElements {
+    [elemName: string]: any // eslint-disable-line
+  }
+}
diff --git a/packages/slate-hyperscript/src/creators.ts b/packages/slate-hyperscript/src/creators.ts
index 32d4112447..d0ef89e3e8 100644
--- a/packages/slate-hyperscript/src/creators.ts
+++ b/packages/slate-hyperscript/src/creators.ts
@@ -237,7 +237,7 @@ export function createEditor(
   const selection: Partial<Range> = {}
   const editor = makeEditor()
   Object.assign(editor, attributes)
-  editor.children = descendants
+  editor.children = descendants as Element[]
 
   // Search the document's texts to see if any of them have tokens associated
   // that need incorporated into the selection.
diff --git a/packages/slate-hyperscript/test/jsx.d.ts b/packages/slate-hyperscript/test/jsx.d.ts
new file mode 100644
index 0000000000..de69552d4c
--- /dev/null
+++ b/packages/slate-hyperscript/test/jsx.d.ts
@@ -0,0 +1,6 @@
+// This allows tests to include Slate Nodes written in JSX without TypeScript complaining.
+declare namespace jsx.JSX {
+  interface IntrinsicElements {
+    [elemName: string]: any // eslint-disable-line
+  }
+}
diff --git a/packages/slate-react/package.json b/packages/slate-react/package.json
index 237b1af703..4dba4277d4 100644
--- a/packages/slate-react/package.json
+++ b/packages/slate-react/package.json
@@ -24,6 +24,7 @@
   },
   "devDependencies": {
     "slate": "^0.58.4",
+    "slate-history": "^0.58.4",
     "slate-hyperscript": "^0.58.4"
   },
   "peerDependencies": {
diff --git a/packages/slate-react/src/components/editable.tsx b/packages/slate-react/src/components/editable.tsx
index df6a86e813..8ae2d3b947 100644
--- a/packages/slate-react/src/components/editable.tsx
+++ b/packages/slate-react/src/components/editable.tsx
@@ -9,6 +9,7 @@ import {
   Transforms,
   Path,
 } from 'slate'
+import { HistoryEditor } from 'slate-history'
 import throttle from 'lodash/throttle'
 import scrollIntoView from 'scroll-into-view-if-needed'
 
@@ -751,7 +752,7 @@ export const Editable = (props: EditableProps) => {
               if (Hotkeys.isRedo(nativeEvent)) {
                 event.preventDefault()
 
-                if (typeof editor.redo === 'function') {
+                if (HistoryEditor.isHistoryEditor(editor)) {
                   editor.redo()
                 }
 
@@ -761,7 +762,7 @@ export const Editable = (props: EditableProps) => {
               if (Hotkeys.isUndo(nativeEvent)) {
                 event.preventDefault()
 
-                if (typeof editor.undo === 'function') {
+                if (HistoryEditor.isHistoryEditor(editor)) {
                   editor.undo()
                 }
 
diff --git a/packages/slate-react/src/components/leaf.tsx b/packages/slate-react/src/components/leaf.tsx
index defbb25351..a6e6f86f51 100644
--- a/packages/slate-react/src/components/leaf.tsx
+++ b/packages/slate-react/src/components/leaf.tsx
@@ -1,6 +1,5 @@
 import React from 'react'
-import { Text, Element } from 'slate'
-
+import { Element, Text } from 'slate'
 import String from './string'
 import { PLACEHOLDER_SYMBOL } from '../utils/weak-maps'
 import { RenderLeafProps } from './editable'
@@ -46,7 +45,7 @@ const Leaf = (props: {
             textDecoration: 'none',
           }}
         >
-          {leaf.placeholder as React.ReactNode}
+          {leaf.placeholder}
         </span>
         {children}
       </React.Fragment>
@@ -75,10 +74,6 @@ const MemoizedLeaf = React.memo(Leaf, (prev, next) => {
   )
 })
 
-/**
- * The default custom leaf renderer.
- */
-
 export const DefaultLeaf = (props: RenderLeafProps) => {
   const { attributes, children } = props
   return <span {...attributes}>{children}</span>
diff --git a/packages/slate-react/src/components/slate.tsx b/packages/slate-react/src/components/slate.tsx
index 82b3caa0ca..a8018c09fb 100644
--- a/packages/slate-react/src/components/slate.tsx
+++ b/packages/slate-react/src/components/slate.tsx
@@ -1,5 +1,5 @@
 import React, { useMemo, useState, useCallback, useEffect } from 'react'
-import { Node } from 'slate'
+import { Node, Element, Descendant } from 'slate'
 
 import { ReactEditor } from '../plugin/react-editor'
 import { FocusedContext } from '../hooks/use-focused'
@@ -14,10 +14,9 @@ import { EDITOR_TO_ON_CHANGE } from '../utils/weak-maps'
 
 export const Slate = (props: {
   editor: ReactEditor
-  value: Node[]
+  value: Descendant[]
   children: React.ReactNode
-  onChange: (value: Node[]) => void
-  [key: string]: unknown
+  onChange: (value: Descendant[]) => void
 }) => {
   const { editor, children, onChange, value, ...rest } = props
   const [key, setKey] = useState(0)
diff --git a/packages/slate-react/src/custom-types.d.ts b/packages/slate-react/src/custom-types.d.ts
new file mode 100644
index 0000000000..8510eb9be6
--- /dev/null
+++ b/packages/slate-react/src/custom-types.d.ts
@@ -0,0 +1,12 @@
+import { CustomTypes } from 'slate'
+
+declare module 'slate' {
+  interface CustomTypes {
+    Text: {
+      placeholder: string
+    }
+    Range: {
+      placeholder?: string
+    }
+  }
+}
diff --git a/packages/slate-react/src/utils/dom.ts b/packages/slate-react/src/utils/dom.ts
index 0736bd4d1a..3bb5ceeea9 100644
--- a/packages/slate-react/src/utils/dom.ts
+++ b/packages/slate-react/src/utils/dom.ts
@@ -12,6 +12,7 @@ import DOMText = globalThis.Text
 import DOMRange = globalThis.Range
 import DOMSelection = globalThis.Selection
 import DOMStaticRange = globalThis.StaticRange
+
 export {
   DOMNode,
   DOMComment,
diff --git a/packages/slate/src/index.ts b/packages/slate/src/index.ts
index 0f898a7751..2088071146 100755
--- a/packages/slate/src/index.ts
+++ b/packages/slate/src/index.ts
@@ -11,4 +11,5 @@ export * from './interfaces/point-ref'
 export * from './interfaces/range'
 export * from './interfaces/range-ref'
 export * from './interfaces/text'
+export * from './interfaces/custom-types'
 export * from './transforms'
diff --git a/packages/slate/src/interfaces/custom-types.ts b/packages/slate/src/interfaces/custom-types.ts
new file mode 100644
index 0000000000..d85d64324b
--- /dev/null
+++ b/packages/slate/src/interfaces/custom-types.ts
@@ -0,0 +1,11 @@
+/**
+ * Extendable Custom Types Interface
+ */
+
+export interface CustomTypes {
+  [key: string]: unknown
+}
+
+export type ExtendedType<K extends string, B> = unknown extends CustomTypes[K]
+  ? B
+  : B & CustomTypes[K]
diff --git a/packages/slate/src/interfaces/editor.ts b/packages/slate/src/interfaces/editor.ts
index 7340e60326..a9ef14487f 100755
--- a/packages/slate/src/interfaces/editor.ts
+++ b/packages/slate/src/interfaces/editor.ts
@@ -4,8 +4,7 @@ import { reverse as reverseText } from 'esrever'
 
 import {
   Ancestor,
-  Descendant,
-  Element,
+  ExtendedType,
   Location,
   Node,
   NodeEntry,
@@ -27,18 +26,19 @@ import {
   RANGE_REFS,
 } from '../utils/weak-maps'
 import { getWordDistance, getCharacterDistance } from '../utils/string'
+import { Descendant } from './node'
+import { Element } from './element'
 
 /**
  * The `Editor` interface stores all the state of a Slate editor. It is extended
  * by plugins that wish to add their own helpers and implement new behaviors.
  */
 
-export interface Editor {
-  children: Node[]
+export interface BaseEditor {
+  children: Descendant[]
   selection: Range | null
   operations: Operation[]
-  marks: Record<string, any> | null
-  [key: string]: unknown
+  marks: Omit<Text, 'text'> | null
 
   // Schema-specific node behaviors.
   isInline: (element: Element) => boolean
@@ -60,6 +60,8 @@ export interface Editor {
   removeMark: (key: string) => void
 }
 
+export type Editor = ExtendedType<'Editor', BaseEditor>
+
 export const Editor = {
   /**
    * Get the ancestor above a location in the document.
@@ -554,7 +556,7 @@ export const Editor = {
    * Get the matching node in the branch of the document after a location.
    */
 
-  next<T extends Node>(
+  next<T extends Descendant>(
     editor: Editor,
     options: {
       at?: Location
diff --git a/packages/slate/src/interfaces/element.ts b/packages/slate/src/interfaces/element.ts
index 34361e8c2a..d7b6b93f9b 100755
--- a/packages/slate/src/interfaces/element.ts
+++ b/packages/slate/src/interfaces/element.ts
@@ -1,5 +1,5 @@
 import isPlainObject from 'is-plain-object'
-import { Editor, Node, Path } from '..'
+import { Editor, Node, Path, Descendant, ExtendedType, Ancestor } from '..'
 
 /**
  * `Element` objects are a type of node in a Slate document that contain other
@@ -7,12 +7,20 @@ import { Editor, Node, Path } from '..'
  * depending on the Slate editor's configuration.
  */
 
-export interface Element {
-  children: Node[]
-  [key: string]: unknown
+export interface BaseElement {
+  children: Descendant[]
 }
+export type Element = ExtendedType<'Element', BaseElement>
 
 export const Element = {
+  /**
+   * Check if a value implements the 'Ancestor' interface.
+   */
+
+  isAncestor(value: any): value is Ancestor {
+    return isPlainObject(value) && Node.isNodeList(value.children)
+  },
+
   /**
    * Check if a value implements the `Element` interface.
    */
@@ -36,6 +44,14 @@ export const Element = {
     )
   },
 
+  /**
+   * Check if a set of props is a partial of Element.
+   */
+
+  isElementProps(props: any): props is Partial<Element> {
+    return (props as Partial<Element>).children !== undefined
+  },
+
   /**
    * Check if an element matches set of properties.
    *
diff --git a/packages/slate/src/interfaces/node.ts b/packages/slate/src/interfaces/node.ts
index ab5794d992..d762f3d5be 100755
--- a/packages/slate/src/interfaces/node.ts
+++ b/packages/slate/src/interfaces/node.ts
@@ -1,12 +1,15 @@
 import { produce } from 'immer'
-import { Editor, Element, ElementEntry, Path, Range, Text } from '..'
+import { Editor, Path, Range, Text } from '..'
+import { Element, ElementEntry } from './element'
+import { ExtendedType } from './custom-types'
 
 /**
  * The `Node` union type represents all of the different types of nodes that
  * occur in a Slate document tree.
  */
 
-export type Node = Editor | Element | Text
+export type BaseNode = Editor | Element | Text
+export type Node = ExtendedType<'Node', BaseNode>
 
 export const Node = {
   /**
@@ -164,6 +167,22 @@ export const Node = {
     }
   },
 
+  /**
+   * Extract props from a Node.
+   */
+
+  extractProps(node: Node): Partial<Node> {
+    if (Element.isAncestor(node)) {
+      const { children, ...properties } = node
+
+      return properties
+    } else {
+      const { text, ...properties } = node
+
+      return properties
+    }
+  },
+
   /**
    * Get the first node entry in a root node from a path.
    */
@@ -222,7 +241,7 @@ export const Node = {
         }
       }
 
-      delete r.selection
+      if (Editor.isEditor(r)) delete r.selection
     })
 
     return newRoot.children
@@ -354,8 +373,12 @@ export const Node = {
 
   matches(node: Node, props: Partial<Node>): boolean {
     return (
-      (Element.isElement(node) && Element.matches(node, props)) ||
-      (Text.isText(node) && Text.matches(node, props))
+      (Element.isElement(node) &&
+        Element.isElementProps(props) &&
+        Element.matches(node, props)) ||
+      (Text.isText(node) &&
+        Text.isTextProps(props) &&
+        Text.matches(node, props))
     )
   },
 
diff --git a/packages/slate/src/interfaces/operation.ts b/packages/slate/src/interfaces/operation.ts
index 87b4c3a0cc..7205918a73 100755
--- a/packages/slate/src/interfaces/operation.ts
+++ b/packages/slate/src/interfaces/operation.ts
@@ -1,87 +1,121 @@
-import { Node, Path, Range } from '..'
+import { ExtendedType, Node, Path, Range } from '..'
 import isPlainObject from 'is-plain-object'
 
-export type InsertNodeOperation = {
+export type BaseInsertNodeOperation = {
   type: 'insert_node'
   path: Path
   node: Node
-  [key: string]: unknown
 }
 
-export type InsertTextOperation = {
+export type InsertNodeOperation = ExtendedType<
+  'InsertNodeOperation',
+  BaseInsertNodeOperation
+>
+
+export type BaseInsertTextOperation = {
   type: 'insert_text'
   path: Path
   offset: number
   text: string
-  [key: string]: unknown
 }
 
-export type MergeNodeOperation = {
+export type InsertTextOperation = ExtendedType<
+  'InsertTextOperation',
+  BaseInsertTextOperation
+>
+
+export type BaseMergeNodeOperation = {
   type: 'merge_node'
   path: Path
   position: number
   properties: Partial<Node>
-  [key: string]: unknown
 }
 
-export type MoveNodeOperation = {
+export type MergeNodeOperation = ExtendedType<
+  'MergeNodeOperation',
+  BaseMergeNodeOperation
+>
+
+export type BaseMoveNodeOperation = {
   type: 'move_node'
   path: Path
   newPath: Path
-  [key: string]: unknown
 }
 
-export type RemoveNodeOperation = {
+export type MoveNodeOperation = ExtendedType<
+  'MoveNodeOperation',
+  BaseMoveNodeOperation
+>
+
+export type BaseRemoveNodeOperation = {
   type: 'remove_node'
   path: Path
   node: Node
-  [key: string]: unknown
 }
 
-export type RemoveTextOperation = {
+export type RemoveNodeOperation = ExtendedType<
+  'RemoveNodeOperation',
+  BaseRemoveNodeOperation
+>
+
+export type BaseRemoveTextOperation = {
   type: 'remove_text'
   path: Path
   offset: number
   text: string
-  [key: string]: unknown
 }
 
-export type SetNodeOperation = {
+export type RemoveTextOperation = ExtendedType<
+  'RemoveTextOperation',
+  BaseRemoveTextOperation
+>
+
+export type BaseSetNodeOperation = {
   type: 'set_node'
   path: Path
   properties: Partial<Node>
   newProperties: Partial<Node>
-  [key: string]: unknown
 }
 
-export type SetSelectionOperation =
+export type SetNodeOperation = ExtendedType<
+  'SetNodeOperation',
+  BaseSetNodeOperation
+>
+
+export type BaseSetSelectionOperation =
   | {
       type: 'set_selection'
-      [key: string]: unknown
       properties: null
       newProperties: Range
     }
   | {
       type: 'set_selection'
-      [key: string]: unknown
       properties: Partial<Range>
       newProperties: Partial<Range>
     }
   | {
       type: 'set_selection'
-      [key: string]: unknown
       properties: Range
       newProperties: null
     }
 
-export type SplitNodeOperation = {
+export type SetSelectionOperation = ExtendedType<
+  'SetSelectionOperation',
+  BaseSetSelectionOperation
+>
+
+export type BaseSplitNodeOperation = {
   type: 'split_node'
   path: Path
   position: number
   properties: Partial<Node>
-  [key: string]: unknown
 }
 
+export type SplitNodeOperation = ExtendedType<
+  'SplitNodeOperation',
+  BaseSplitNodeOperation
+>
+
 export type NodeOperation =
   | InsertNodeOperation
   | MergeNodeOperation
diff --git a/packages/slate/src/interfaces/point.ts b/packages/slate/src/interfaces/point.ts
index 971b6486cf..29f818f975 100755
--- a/packages/slate/src/interfaces/point.ts
+++ b/packages/slate/src/interfaces/point.ts
@@ -1,6 +1,6 @@
 import isPlainObject from 'is-plain-object'
 import { produce } from 'immer'
-import { Operation, Path } from '..'
+import { ExtendedType, Operation, Path } from '..'
 
 /**
  * `Point` objects refer to a specific location in a text node in a Slate
@@ -9,12 +9,13 @@ import { Operation, Path } from '..'
  * only refer to `Text` nodes.
  */
 
-export interface Point {
+export interface BasePoint {
   path: Path
   offset: number
-  [key: string]: unknown
 }
 
+export type Point = ExtendedType<'Point', BasePoint>
+
 export const Point = {
   /**
    * Compare a point to another, returning an integer indicating whether the
diff --git a/packages/slate/src/interfaces/range.ts b/packages/slate/src/interfaces/range.ts
index 76f5494c7a..706633fa3f 100755
--- a/packages/slate/src/interfaces/range.ts
+++ b/packages/slate/src/interfaces/range.ts
@@ -1,6 +1,6 @@
 import { produce } from 'immer'
 import isPlainObject from 'is-plain-object'
-import { Operation, Path, Point, PointEntry } from '..'
+import { ExtendedType, Operation, Path, Point, PointEntry } from '..'
 
 /**
  * `Range` objects are a set of points that refer to a specific span of a Slate
@@ -8,12 +8,13 @@ import { Operation, Path, Point, PointEntry } from '..'
  * multiple nodes.
  */
 
-export interface Range {
+export interface BaseRange {
   anchor: Point
   focus: Point
-  [key: string]: unknown
 }
 
+export type Range = ExtendedType<'Range', BaseRange>
+
 export const Range = {
   /**
    * Get the start and end points of a range, in the order in which they appear
diff --git a/packages/slate/src/interfaces/text.ts b/packages/slate/src/interfaces/text.ts
index 96eb750c4c..69dd2ba72e 100755
--- a/packages/slate/src/interfaces/text.ts
+++ b/packages/slate/src/interfaces/text.ts
@@ -1,5 +1,6 @@
 import isPlainObject from 'is-plain-object'
 import { Range } from '..'
+import { ExtendedType } from './custom-types'
 
 /**
  * `Text` objects represent the nodes that contain the actual text content of a
@@ -7,11 +8,12 @@ import { Range } from '..'
  * nodes in the document tree as they cannot contain any children.
  */
 
-export interface Text {
+export interface BaseText {
   text: string
-  [key: string]: unknown
 }
 
+export type Text = ExtendedType<'Text', BaseText>
+
 export const Text = {
   /**
    * Check if two text nodes are equal.
@@ -63,6 +65,14 @@ export const Text = {
     return Array.isArray(value) && (value.length === 0 || Text.isText(value[0]))
   },
 
+  /**
+   * Check if some props are a partial of Text.
+   */
+
+  isTextProps(props: any): props is Partial<Text> {
+    return (props as Partial<Text>).text !== undefined
+  },
+
   /**
    * Check if an text matches set of properties.
    *
diff --git a/packages/slate/src/transforms/general.ts b/packages/slate/src/transforms/general.ts
index 5b170dfd46..411dfdd507 100755
--- a/packages/slate/src/transforms/general.ts
+++ b/packages/slate/src/transforms/general.ts
@@ -272,7 +272,7 @@ export const GeneralTransforms = {
       }
     }
 
-    editor.children = finishDraft(editor.children) as Node[]
+    editor.children = finishDraft(editor.children) as Descendant[]
 
     if (selection) {
       editor.selection = isDraft(selection)
diff --git a/packages/slate/src/transforms/index.ts b/packages/slate/src/transforms/index.ts
index ad7975bb15..ce59a7ab5a 100644
--- a/packages/slate/src/transforms/index.ts
+++ b/packages/slate/src/transforms/index.ts
@@ -3,9 +3,16 @@ import { NodeTransforms } from './node'
 import { SelectionTransforms } from './selection'
 import { TextTransforms } from './text'
 
-export const Transforms = {
-  ...GeneralTransforms,
-  ...NodeTransforms,
-  ...SelectionTransforms,
-  ...TextTransforms,
-}
+type TransformsType = typeof GeneralTransforms &
+  typeof NodeTransforms &
+  typeof SelectionTransforms &
+  typeof TextTransforms
+
+const Transforms: TransformsType = Object.assign(
+  GeneralTransforms,
+  NodeTransforms,
+  SelectionTransforms,
+  TextTransforms
+)
+
+export { Transforms }
diff --git a/packages/slate/src/transforms/node.ts b/packages/slate/src/transforms/node.ts
index 2d4084158f..148275cb68 100644
--- a/packages/slate/src/transforms/node.ts
+++ b/packages/slate/src/transforms/node.ts
@@ -1,7 +1,7 @@
 import {
   Editor,
-  Element,
   Location,
+  Descendant,
   Node,
   Path,
   Point,
@@ -11,6 +11,7 @@ import {
   NodeEntry,
   Ancestor,
 } from '..'
+import { Element } from '../interfaces/element'
 
 export const NodeTransforms = {
   /**
@@ -631,7 +632,7 @@ export const NodeTransforms = {
 
         if (always || !beforeRef || !Editor.isEdge(editor, point, path)) {
           split = true
-          const { text, children, ...properties } = node
+          const properties = Node.extractProps(node)
           editor.apply({
             type: 'split_node',
             path,
@@ -720,7 +721,7 @@ export const NodeTransforms = {
 
       for (const pathRef of pathRefs) {
         const path = pathRef.unref()!
-        const [node] = Editor.node(editor, path) as NodeEntry<Ancestor>
+        const [node] = Editor.node(editor, path)
         let range = Editor.range(editor, path)
 
         if (split && rangeRef) {
@@ -729,7 +730,7 @@ export const NodeTransforms = {
 
         Transforms.liftNodes(editor, {
           at: range,
-          match: n => node.children.includes(n),
+          match: n => Element.isAncestor(node) && node.children.includes(n),
           voids,
         })
       }
@@ -823,7 +824,7 @@ export const NodeTransforms = {
 
           const range = Editor.range(editor, firstPath, lastPath)
           const commonNodeEntry = Editor.node(editor, commonPath)
-          const [commonNode] = commonNodeEntry as NodeEntry<Ancestor>
+          const [commonNode] = commonNodeEntry
           const depth = commonPath.length + 1
           const wrapperPath = Path.next(lastPath.slice(0, depth))
           const wrapper = { ...element, children: [] }
@@ -831,7 +832,8 @@ export const NodeTransforms = {
 
           Transforms.moveNodes(editor, {
             at: range,
-            match: n => commonNode.children.includes(n),
+            match: n =>
+              Element.isAncestor(commonNode) && commonNode.children.includes(n),
             to: wrapperPath.concat(0),
             voids,
           })
diff --git a/packages/slate/test/interfaces/CustomTypes/boldText-false.tsx b/packages/slate/test/interfaces/CustomTypes/boldText-false.tsx
new file mode 100644
index 0000000000..d152c9bfbb
--- /dev/null
+++ b/packages/slate/test/interfaces/CustomTypes/boldText-false.tsx
@@ -0,0 +1,11 @@
+import { Text } from 'slate'
+import { isBoldText } from './type-guards'
+
+export const input: Text = {
+  placeholder: 'heading',
+  text: 'mytext',
+}
+
+export const test = isBoldText
+
+export const output = false
diff --git a/packages/slate/test/interfaces/CustomTypes/boldText-true.tsx b/packages/slate/test/interfaces/CustomTypes/boldText-true.tsx
new file mode 100644
index 0000000000..9fa528eebc
--- /dev/null
+++ b/packages/slate/test/interfaces/CustomTypes/boldText-true.tsx
@@ -0,0 +1,12 @@
+// show that regular methods that are imported work as expected
+import { Text } from 'slate'
+import { isBoldText } from './type-guards'
+
+export const input: Text = {
+  bold: true,
+  text: 'mytext',
+}
+
+export const test = isBoldText
+
+export const output = true
diff --git a/packages/slate/test/interfaces/CustomTypes/custom-types.ts b/packages/slate/test/interfaces/CustomTypes/custom-types.ts
new file mode 100644
index 0000000000..caddc00822
--- /dev/null
+++ b/packages/slate/test/interfaces/CustomTypes/custom-types.ts
@@ -0,0 +1,30 @@
+import { Descendant, Element, Text, CustomTypes } from 'slate'
+
+export interface HeadingElement {
+  type: 'heading'
+  level: number
+  children: Descendant[]
+}
+
+export interface ListItemElement {
+  type: 'list-item'
+  depth: number
+  children: Descendant[]
+}
+
+export interface CustomText {
+  placeholder: string
+  text: string
+}
+
+export interface BoldCustomText {
+  bold: boolean
+  text: string
+}
+
+declare module 'slate' {
+  interface CustomTypes {
+    Element: HeadingElement | ListItemElement
+    Text: CustomText | BoldCustomText
+  }
+}
diff --git a/packages/slate/test/interfaces/CustomTypes/customText-false.tsx b/packages/slate/test/interfaces/CustomTypes/customText-false.tsx
new file mode 100644
index 0000000000..c1cff79c73
--- /dev/null
+++ b/packages/slate/test/interfaces/CustomTypes/customText-false.tsx
@@ -0,0 +1,11 @@
+import { Text } from 'slate'
+import { isCustomText } from './type-guards'
+
+export const input: Text = {
+  bold: true,
+  text: 'mytext',
+}
+
+export const test = isCustomText
+
+export const output = false
diff --git a/packages/slate/test/interfaces/CustomTypes/customText-true.tsx b/packages/slate/test/interfaces/CustomTypes/customText-true.tsx
new file mode 100644
index 0000000000..dc801f15c2
--- /dev/null
+++ b/packages/slate/test/interfaces/CustomTypes/customText-true.tsx
@@ -0,0 +1,11 @@
+import { Text } from 'slate'
+import { isCustomText } from './type-guards'
+
+export const input: Text = {
+  placeholder: 'mystring',
+  text: 'mytext',
+}
+
+export const test = isCustomText
+
+export const output = true
diff --git a/packages/slate/test/interfaces/CustomTypes/headingElement-false.tsx b/packages/slate/test/interfaces/CustomTypes/headingElement-false.tsx
new file mode 100644
index 0000000000..196c235c32
--- /dev/null
+++ b/packages/slate/test/interfaces/CustomTypes/headingElement-false.tsx
@@ -0,0 +1,12 @@
+import { Element } from 'slate'
+import { isHeadingElement } from './type-guards'
+
+export const input: Element = {
+  type: 'list-item',
+  depth: 5,
+  children: [],
+}
+
+export const test = isHeadingElement
+
+export const output = false
diff --git a/packages/slate/test/interfaces/CustomTypes/headingElement-true.tsx b/packages/slate/test/interfaces/CustomTypes/headingElement-true.tsx
new file mode 100644
index 0000000000..633138a0fc
--- /dev/null
+++ b/packages/slate/test/interfaces/CustomTypes/headingElement-true.tsx
@@ -0,0 +1,12 @@
+import { Element } from 'slate'
+import { isHeadingElement } from './type-guards'
+
+export const input: Element = {
+  type: 'heading',
+  level: 5,
+  children: [],
+}
+
+export const test = isHeadingElement
+
+export const output = true
diff --git a/packages/slate/test/interfaces/CustomTypes/type-guards.ts b/packages/slate/test/interfaces/CustomTypes/type-guards.ts
new file mode 100644
index 0000000000..3a898a567b
--- /dev/null
+++ b/packages/slate/test/interfaces/CustomTypes/type-guards.ts
@@ -0,0 +1,11 @@
+import { Element, Text } from 'slate'
+import { BoldCustomText, CustomText, HeadingElement } from './custom-types'
+
+export const isBoldText = (text: Text): text is BoldCustomText =>
+  !!(text as BoldCustomText).bold
+
+export const isCustomText = (text: Text): text is CustomText =>
+  !!(text as CustomText).placeholder
+
+export const isHeadingElement = (element: Element): element is HeadingElement =>
+  element.type === 'heading'
diff --git a/packages/slate/test/interfaces/Element/isElement/boolean.tsx b/packages/slate/test/interfaces/Element/isElement/boolean.tsx
index 822c40a9b5..ad65825481 100644
--- a/packages/slate/test/interfaces/Element/isElement/boolean.tsx
+++ b/packages/slate/test/interfaces/Element/isElement/boolean.tsx
@@ -4,4 +4,5 @@ export const input = true
 export const test = value => {
   return Element.isElement(value)
 }
+
 export const output = false
diff --git a/packages/slate/test/jsx.d.ts b/packages/slate/test/jsx.d.ts
new file mode 100644
index 0000000000..de69552d4c
--- /dev/null
+++ b/packages/slate/test/jsx.d.ts
@@ -0,0 +1,6 @@
+// This allows tests to include Slate Nodes written in JSX without TypeScript complaining.
+declare namespace jsx.JSX {
+  interface IntrinsicElements {
+    [elemName: string]: any // eslint-disable-line
+  }
+}
diff --git a/site/examples/check-lists.tsx b/site/examples/check-lists.tsx
index ec55e59b64..fd5bb537d3 100644
--- a/site/examples/check-lists.tsx
+++ b/site/examples/check-lists.tsx
@@ -7,12 +7,67 @@ import {
   useReadOnly,
   ReactEditor,
 } from 'slate-react'
-import { Node, Editor, Transforms, Range, Point, createEditor } from 'slate'
+import {
+  Node,
+  Editor,
+  Transforms,
+  Range,
+  Point,
+  createEditor,
+  Descendant,
+  Element as SlateElement,
+} from 'slate'
 import { css } from 'emotion'
 import { withHistory } from 'slate-history'
 
+const initialValue: Descendant[] = [
+  {
+    type: 'paragraph',
+    children: [
+      {
+        text:
+          'With Slate you can build complex block types that have their own embedded content and behaviors, like rendering checkboxes inside check list items!',
+      },
+    ],
+  },
+  {
+    type: 'check-list-item',
+    checked: true,
+    children: [{ text: 'Slide to the left.' }],
+  },
+  {
+    type: 'check-list-item',
+    checked: true,
+    children: [{ text: 'Slide to the right.' }],
+  },
+  {
+    type: 'check-list-item',
+    checked: false,
+    children: [{ text: 'Criss-cross.' }],
+  },
+  {
+    type: 'check-list-item',
+    checked: true,
+    children: [{ text: 'Criss-cross!' }],
+  },
+  {
+    type: 'check-list-item',
+    checked: false,
+    children: [{ text: 'Cha cha real smooth…' }],
+  },
+  {
+    type: 'check-list-item',
+    checked: false,
+    children: [{ text: "Let's go to work!" }],
+  },
+  {
+    type: 'paragraph',
+    children: [{ text: 'Try it out for yourself!' }],
+  },
+]
+
 const CheckListsExample = () => {
-  const [value, setValue] = useState<Node[]>(initialValue)
+  const [value, setValue] = useState<Descendant[]>(initialValue)
   const renderElement = useCallback(props => <Element {...props} />, [])
   const editor = useMemo(
     () => withChecklists(withHistory(withReact(createEditor()))),
@@ -39,7 +94,10 @@ const withChecklists = editor => {
 
     if (selection && Range.isCollapsed(selection)) {
       const [match] = Editor.nodes(editor, {
-        match: n => n.type === 'check-list-item',
+        match: n =>
+          !Editor.isEditor(n) &&
+          SlateElement.isElement(n) &&
+          n.type === 'check-list-item',
       })
 
       if (match) {
@@ -47,11 +105,15 @@ const withChecklists = editor => {
         const start = Editor.start(editor, path)
 
         if (Point.equals(selection.anchor, start)) {
-          Transforms.setNodes(
-            editor,
-            { type: 'paragraph' },
-            { match: n => n.type === 'check-list-item' }
-          )
+          const newProperties: Partial<SlateElement> = {
+            type: 'paragraph',
+          }
+          Transforms.setNodes(editor, newProperties, {
+            match: n =>
+              !Editor.isEditor(n) &&
+              SlateElement.isElement(n) &&
+              n.type === 'check-list-item',
+          })
           return
         }
       }
@@ -102,11 +164,10 @@ const CheckListItemElement = ({ attributes, children, element }) => {
           checked={checked}
           onChange={event => {
             const path = ReactEditor.findPath(editor, element)
-            Transforms.setNodes(
-              editor,
-              { checked: event.target.checked },
-              { at: path }
-            )
+            const newProperties: Partial<SlateElement> = {
+              checked: event.target.checked,
+            }
+            Transforms.setNodes(editor, newProperties, { at: path })
           }}
         />
       </span>
@@ -129,48 +190,4 @@ const CheckListItemElement = ({ attributes, children, element }) => {
   )
 }
 
-const initialValue = [
-  {
-    children: [
-      {
-        text:
-          'With Slate you can build complex block types that have their own embedded content and behaviors, like rendering checkboxes inside check list items!',
-      },
-    ],
-  },
-  {
-    type: 'check-list-item',
-    checked: true,
-    children: [{ text: 'Slide to the left.' }],
-  },
-  {
-    type: 'check-list-item',
-    checked: true,
-    children: [{ text: 'Slide to the right.' }],
-  },
-  {
-    type: 'check-list-item',
-    checked: false,
-    children: [{ text: 'Criss-cross.' }],
-  },
-  {
-    type: 'check-list-item',
-    checked: true,
-    children: [{ text: 'Criss-cross!' }],
-  },
-  {
-    type: 'check-list-item',
-    checked: false,
-    children: [{ text: 'Cha cha real smooth…' }],
-  },
-  {
-    type: 'check-list-item',
-    checked: false,
-    children: [{ text: "Let's go to work!" }],
-  },
-  {
-    children: [{ text: 'Try it out for yourself!' }],
-  },
-]
-
 export default CheckListsExample
diff --git a/site/examples/code-highlighting.tsx b/site/examples/code-highlighting.tsx
index 6669ed050c..a93f1fc264 100644
--- a/site/examples/code-highlighting.tsx
+++ b/site/examples/code-highlighting.tsx
@@ -5,7 +5,14 @@ import 'prismjs/components/prism-sql'
 import 'prismjs/components/prism-java'
 import React, { useState, useCallback, useMemo } from 'react'
 import { Slate, Editable, withReact } from 'slate-react'
-import { Text, createEditor, Node } from 'slate'
+import {
+  Text,
+  createEditor,
+  Node,
+  Element as SlateElement,
+  BaseEditor,
+  Descendant,
+} from 'slate'
 import { withHistory } from 'slate-history'
 import { css } from 'emotion'
 
diff --git a/site/examples/custom-types.d.ts b/site/examples/custom-types.d.ts
new file mode 100644
index 0000000000..7764a72b86
--- /dev/null
+++ b/site/examples/custom-types.d.ts
@@ -0,0 +1,17 @@
+import { Text, Editor, Descendant } from 'slate'
+
+declare module 'slate' {
+  interface CustomTypes {
+    Element: CustomElement
+    Node: CustomNode
+  }
+}
+
+interface CustomElement {
+  type?: string
+  checked?: boolean
+  url?: string
+  children: Descendant[]
+}
+
+type CustomNode = Editor | CustomElement | Text
diff --git a/site/examples/embeds.tsx b/site/examples/embeds.tsx
index c7eccc05ca..4e7bbea3d2 100644
--- a/site/examples/embeds.tsx
+++ b/site/examples/embeds.tsx
@@ -1,5 +1,5 @@
 import React, { useState, useMemo } from 'react'
-import { Transforms, createEditor, Node } from 'slate'
+import { Transforms, createEditor, Node, Element as SlateElement } from 'slate'
 import {
   Slate,
   Editable,
@@ -67,7 +67,10 @@ const VideoElement = ({ attributes, children, element }) => {
           url={url}
           onChange={val => {
             const path = ReactEditor.findPath(editor, element)
-            Transforms.setNodes(editor, { url: val }, { at: path })
+            const newProperties: Partial<SlateElement> = {
+              url: val,
+            }
+            Transforms.setNodes(editor, newProperties, { at: path })
           }}
         />
       </div>
diff --git a/site/examples/forced-layout.tsx b/site/examples/forced-layout.tsx
index f10e2bd81a..0bcebd3523 100644
--- a/site/examples/forced-layout.tsx
+++ b/site/examples/forced-layout.tsx
@@ -1,6 +1,6 @@
 import React, { useState, useCallback, useMemo } from 'react'
 import { Slate, Editable, withReact } from 'slate-react'
-import { Transforms, createEditor, Node } from 'slate'
+import { Transforms, createEditor, Node, Element as SlateElement } from 'slate'
 import { withHistory } from 'slate-history'
 
 const withLayout = editor => {
@@ -21,8 +21,9 @@ const withLayout = editor => {
       for (const [child, childPath] of Node.children(editor, path)) {
         const type = childPath[0] === 0 ? 'title' : 'paragraph'
 
-        if (child.type !== type) {
-          Transforms.setNodes(editor, { type }, { at: childPath })
+        if (SlateElement.isElement(child) && child.type !== type) {
+          const newProperties: Partial<SlateElement> = { type }
+          Transforms.setNodes(editor, newProperties, { at: childPath })
         }
       }
     }
diff --git a/site/examples/links.tsx b/site/examples/links.tsx
index e5b1201fe3..7b091f2078 100644
--- a/site/examples/links.tsx
+++ b/site/examples/links.tsx
@@ -1,7 +1,14 @@
 import React, { useState, useMemo } from 'react'
 import isUrl from 'is-url'
 import { Slate, Editable, withReact, useSlate } from 'slate-react'
-import { Node, Transforms, Editor, Range, createEditor } from 'slate'
+import {
+  Node,
+  Transforms,
+  Editor,
+  Range,
+  createEditor,
+  Element as SlateElement,
+} from 'slate'
 import { withHistory } from 'slate-history'
 
 import { Button, Icon, Toolbar } from '../components'
@@ -61,12 +68,18 @@ const insertLink = (editor, url) => {
 }
 
 const isLinkActive = editor => {
-  const [link] = Editor.nodes(editor, { match: n => n.type === 'link' })
+  const [link] = Editor.nodes(editor, {
+    match: n =>
+      !Editor.isEditor(n) && SlateElement.isElement(n) && n.type === 'link',
+  })
   return !!link
 }
 
 const unwrapLink = editor => {
-  Transforms.unwrapNodes(editor, { match: n => n.type === 'link' })
+  Transforms.unwrapNodes(editor, {
+    match: n =>
+      !Editor.isEditor(n) && SlateElement.isElement(n) && n.type === 'link',
+  })
 }
 
 const wrapLink = (editor, url) => {
diff --git a/site/examples/markdown-shortcuts.tsx b/site/examples/markdown-shortcuts.tsx
index 68ad98140e..11da5a143d 100644
--- a/site/examples/markdown-shortcuts.tsx
+++ b/site/examples/markdown-shortcuts.tsx
@@ -1,6 +1,14 @@
 import React, { useState, useCallback, useMemo } from 'react'
 import { Slate, Editable, withReact } from 'slate-react'
-import { Node, Editor, Transforms, Range, Point, createEditor } from 'slate'
+import {
+  Node,
+  Editor,
+  Transforms,
+  Range,
+  Point,
+  createEditor,
+  Element as SlateElement,
+} from 'slate'
 import { withHistory } from 'slate-history'
 
 const SHORTCUTS = {
@@ -55,16 +63,20 @@ const withShortcuts = editor => {
       if (type) {
         Transforms.select(editor, range)
         Transforms.delete(editor)
-        Transforms.setNodes(
-          editor,
-          { type },
-          { match: n => Editor.isBlock(editor, n) }
-        )
+        const newProperties: Partial<SlateElement> = {
+          type,
+        }
+        Transforms.setNodes(editor, newProperties, {
+          match: n => Editor.isBlock(editor, n),
+        })
 
         if (type === 'list-item') {
           const list = { type: 'bulleted-list', children: [] }
           Transforms.wrapNodes(editor, list, {
-            match: n => n.type === 'list-item',
+            match: n =>
+              !Editor.isEditor(n) &&
+              SlateElement.isElement(n) &&
+              n.type === 'list-item',
           })
         }
 
@@ -88,14 +100,22 @@ const withShortcuts = editor => {
         const start = Editor.start(editor, path)
 
         if (
+          !Editor.isEditor(block) &&
+          SlateElement.isElement(block) &&
           block.type !== 'paragraph' &&
           Point.equals(selection.anchor, start)
         ) {
-          Transforms.setNodes(editor, { type: 'paragraph' })
+          const newProperties: Partial<SlateElement> = {
+            type: 'paragraph',
+          }
+          Transforms.setNodes(editor, newProperties)
 
           if (block.type === 'list-item') {
             Transforms.unwrapNodes(editor, {
-              match: n => n.type === 'bulleted-list',
+              match: n =>
+                !Editor.isEditor(n) &&
+                SlateElement.isElement(n) &&
+                n.type === 'bulleted-list',
               split: true,
             })
           }
diff --git a/site/examples/richtext.tsx b/site/examples/richtext.tsx
index 8a6d5e8200..3e333ee7b0 100644
--- a/site/examples/richtext.tsx
+++ b/site/examples/richtext.tsx
@@ -1,7 +1,13 @@
 import React, { useCallback, useMemo, useState } from 'react'
 import isHotkey from 'is-hotkey'
 import { Editable, withReact, useSlate, Slate } from 'slate-react'
-import { Editor, Transforms, createEditor, Node } from 'slate'
+import {
+  Editor,
+  Transforms,
+  createEditor,
+  Node,
+  Element as SlateElement,
+} from 'slate'
 import { withHistory } from 'slate-history'
 
 import { Button, Icon, Toolbar } from '../components'
@@ -59,13 +65,16 @@ const toggleBlock = (editor, format) => {
   const isList = LIST_TYPES.includes(format)
 
   Transforms.unwrapNodes(editor, {
-    match: n => LIST_TYPES.includes(n.type as string),
+    match: n =>
+      LIST_TYPES.includes(
+        !Editor.isEditor(n) && SlateElement.isElement(n) && n.type
+      ),
     split: true,
   })
-
-  Transforms.setNodes(editor, {
+  const newProperties: Partial<SlateElement> = {
     type: isActive ? 'paragraph' : isList ? 'list-item' : format,
-  })
+  }
+  Transforms.setNodes(editor, newProperties)
 
   if (!isActive && isList) {
     const block = { type: format, children: [] }
@@ -85,7 +94,8 @@ const toggleMark = (editor, format) => {
 
 const isBlockActive = (editor, format) => {
   const [match] = Editor.nodes(editor, {
-    match: n => n.type === format,
+    match: n =>
+      !Editor.isEditor(n) && SlateElement.isElement(n) && n.type === format,
   })
 
   return !!match
diff --git a/site/examples/tables.tsx b/site/examples/tables.tsx
index 5b3250fcb3..f85a78b397 100644
--- a/site/examples/tables.tsx
+++ b/site/examples/tables.tsx
@@ -1,6 +1,13 @@
 import React, { useState, useCallback, useMemo } from 'react'
 import { Slate, Editable, withReact } from 'slate-react'
-import { Editor, Range, Point, Node, createEditor } from 'slate'
+import {
+  Editor,
+  Range,
+  Point,
+  Node,
+  createEditor,
+  Element as SlateElement,
+} from 'slate'
 import { withHistory } from 'slate-history'
 
 const TablesExample = () => {
@@ -26,7 +33,10 @@ const withTables = editor => {
 
     if (selection && Range.isCollapsed(selection)) {
       const [cell] = Editor.nodes(editor, {
-        match: n => n.type === 'table-cell',
+        match: n =>
+          !Editor.isEditor(n) &&
+          SlateElement.isElement(n) &&
+          n.type === 'table-cell',
       })
 
       if (cell) {
@@ -47,7 +57,10 @@ const withTables = editor => {
 
     if (selection && Range.isCollapsed(selection)) {
       const [cell] = Editor.nodes(editor, {
-        match: n => n.type === 'table-cell',
+        match: n =>
+          !Editor.isEditor(n) &&
+          SlateElement.isElement(n) &&
+          n.type === 'table-cell',
       })
 
       if (cell) {
@@ -67,7 +80,12 @@ const withTables = editor => {
     const { selection } = editor
 
     if (selection) {
-      const [table] = Editor.nodes(editor, { match: n => n.type === 'table' })
+      const [table] = Editor.nodes(editor, {
+        match: n =>
+          !Editor.isEditor(n) &&
+          SlateElement.isElement(n) &&
+          n.type === 'table',
+      })
 
       if (table) {
         return
diff --git a/support/fixtures.js b/support/fixtures.js
index a379b2c136..27507de07c 100644
--- a/support/fixtures.js
+++ b/support/fixtures.js
@@ -25,7 +25,8 @@ export const fixtures = (...args) => {
       }
       if (
         stat.isFile() &&
-        (file.endsWith('.js') || file.endsWith('.ts') || file.endsWith('.tsx')) &&
+        (file.endsWith('.js') ||
+          file.endsWith('.tsx')) &&
         !file.startsWith('.') &&
         // Ignoring `index.js` files allows us to use the fixtures directly
         // from the top-level directory itself, instead of only children.
@@ -34,7 +35,7 @@ export const fixtures = (...args) => {
         const name = basename(file, extname(file))
 
         // This needs to be a non-arrow function to use `this.skip()`.
-        it(`${name} `, function () {
+        it(`${name} `, function() {
           const module = require(p)
 
           if (module.skip) {