diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index fe284ad..69924a4 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -17,5 +17,5 @@ jobs:
     strategy:
       matrix:
         node:
-          - lts/erbium
+          - lts/fermium
           - node
diff --git a/package.json b/package.json
index ce5b853..8355b47 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "mdast-util-gfm-table",
-  "version": "1.0.4",
+  "version": "1.0.5",
   "description": "mdast extension to parse and serialize GFM tables",
   "license": "MIT",
   "keywords": [
@@ -48,7 +48,7 @@
     "c8": "^7.0.0",
     "micromark-extension-gfm-table": "^1.0.0",
     "prettier": "^2.0.0",
-    "remark-cli": "^10.0.0",
+    "remark-cli": "^11.0.0",
     "remark-preset-wooorm": "^9.0.0",
     "rimraf": "^3.0.0",
     "string-width": "^5.0.0",
@@ -56,7 +56,7 @@
     "type-coverage": "^2.0.0",
     "typescript": "^4.0.0",
     "unist-util-remove-position": "^4.0.0",
-    "xo": "^0.48.0"
+    "xo": "^0.52.0"
   },
   "scripts": {
     "build": "rimraf \"lib/**/*.d.ts\" \"*.d.ts\" && tsc && type-coverage",
diff --git a/readme.md b/readme.md
index f112262..073c2d3 100644
--- a/readme.md
+++ b/readme.md
@@ -8,31 +8,76 @@
 [![Backers][backers-badge]][collective]
 [![Chat][chat-badge]][chat]
 
-Extension for [`mdast-util-from-markdown`][from-markdown] and/or
-[`mdast-util-to-markdown`][to-markdown] to support GitHub flavored markdown
-tables in **[mdast][]**.
-When parsing (`from-markdown`), must be combined with
-[`micromark-extension-gfm-table`][extension].
+[mdast][] extensions to parse and serialize [GFM][] tables.
+
+## Contents
+
+*   [What is this?](#what-is-this)
+*   [When to use this](#when-to-use-this)
+*   [Install](#install)
+*   [Use](#use)
+*   [API](#api)
+    *   [`gfmTableFromMarkdown`](#gfmtablefrommarkdown)
+    *   [`gfmTableToMarkdown(options?)`](#gfmtabletomarkdownoptions)
+*   [Examples](#examples)
+    *   [Example: `stringLength`](#example-stringlength)
+*   [Syntax tree](#syntax-tree)
+    *   [Nodes](#nodes)
+    *   [Enumeration](#enumeration)
+    *   [Content model](#content-model)
+*   [Types](#types)
+*   [Compatibility](#compatibility)
+*   [Related](#related)
+*   [Contribute](#contribute)
+*   [License](#license)
+
+## What is this?
+
+This package contains extensions that add support for the table syntax enabled
+by GFM to [`mdast-util-from-markdown`][mdast-util-from-markdown] and
+[`mdast-util-to-markdown`][mdast-util-to-markdown].
 
 ## When to use this
 
-Use [`mdast-util-gfm`][mdast-util-gfm] if you want all of GFM.
-Use this otherwise.
+These tools are all rather low-level.
+In most cases, you’d want to use [`remark-gfm`][remark-gfm] with remark instead.
 
-## Install
+When you are working with syntax trees and want all of GFM, use
+[`mdast-util-gfm`][mdast-util-gfm] instead.
 
-This package is [ESM only](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c):
-Node 12+ is needed to use it and it must be `import`ed instead of `require`d.
+When working with `mdast-util-from-markdown`, you must combine this package with
+[`micromark-extension-gfm-table`][extension].
 
-[npm][]:
+This utility does not handle how markdown is turned to HTML.
+That’s done by [`mdast-util-to-hast`][mdast-util-to-hast].
+If your content is not in English, you should configure that utility.
+
+## Install
+
+This package is [ESM only][esm].
+In Node.js (version 12.20+, 14.14+, or 16.0+), install with [npm][]:
 
 ```sh
 npm install mdast-util-gfm-table
 ```
 
+In Deno with [`esm.sh`][esmsh]:
+
+```js
+import {gfmTableFromMarkdown, gfmTableToMarkdown} from 'https://esm.sh/mdast-util-gfm-table@1'
+```
+
+In browsers with [`esm.sh`][esmsh]:
+
+```html
+<script type="module">
+  import {gfmTableFromMarkdown, gfmTableToMarkdown} from 'https://esm.sh/mdast-util-gfm-table@1?bundle'
+</script>
+```
+
 ## Use
 
-Say we have the following file, `example.md`:
+Say our document `example.md` contains:
 
 ```markdown
 | a | b | c | d |
@@ -41,16 +86,16 @@ Say we have the following file, `example.md`:
 | g | h | i | j | k |
 ```
 
-And our module, `example.js`, looks as follows:
+…and our module `example.js` looks as follows:
 
 ```js
-import fs from 'node:fs'
+import fs from 'node:fs/promises'
 import {fromMarkdown} from 'mdast-util-from-markdown'
 import {toMarkdown} from 'mdast-util-to-markdown'
 import {gfmTable} from 'micromark-extension-gfm-table'
 import {gfmTableFromMarkdown, gfmTableToMarkdown} from 'mdast-util-gfm-table'
 
-const doc = fs.readFileSync('example.md')
+const doc = await fs.readFile('example.md')
 
 const tree = fromMarkdown(doc, {
   extensions: [gfmTable],
@@ -64,8 +109,7 @@ const out = toMarkdown(tree, {extensions: [gfmTableToMarkdown()]})
 console.log(out)
 ```
 
-Now, running `node example` yields (positional info removed for the sake of
-brevity):
+…now running `node example.js` yields (positional info removed for brevity):
 
 ```js
 {
@@ -116,57 +160,303 @@ brevity):
 
 ## API
 
-This package exports the following identifier: `gfmTableFromMarkdown`,
+This package exports the identifiers `gfmTableFromMarkdown` and
 `gfmTableToMarkdown`.
 There is no default export.
 
 ### `gfmTableFromMarkdown`
 
+Extension for [`mdast-util-from-markdown`][mdast-util-from-markdown].
+
 ### `gfmTableToMarkdown(options?)`
 
-Support GFM tables.
-The exports of `fromMarkdown` is an extension for
-[`mdast-util-from-markdown`][from-markdown].
-The export of `toMarkdown` is a function that can be called with options and
-returns an extension for [`mdast-util-to-markdown`][to-markdown].
+Function that can be called to get an extension for
+[`mdast-util-to-markdown`][mdast-util-to-markdown].
 
 ##### `options`
 
+Configuration (optional).
+
 ###### `options.tableCellPadding`
 
-Create tables with a space between cell delimiters (`|`) and content (`boolean`,
-default: `true`).
+Serialize tables with a space between delimiters (`|`) and cell content
+(`boolean`, default: `true`).
 
 ###### `options.tablePipeAlign`
 
-Align the delimiters (`|`) between table cells so that they all align nicely and
-form a grid (`boolean`, default: `true`).
+Serialize by aligning the delimiters (`|`) between table cells so that they all
+align nicely and form a grid (`boolean`, default: `true`).
 
 ###### `options.stringLength`
 
-Function passed to [`markdown-table`][markdown-table] to detect the length of a
-table cell (`Function`, default: [`s => s.length`][string-length]).
-Used to pad tables.
+Function to detect the length of table cell content (`Function`, default:
+`s => s.length`).
+This is used when aligning the delimiters (`|`) between table cells.
+Full-width characters and emoji mess up delimiter alignment when viewing the
+markdown source.
+To fix this, you can pass this function, which receives the cell content and
+returns its “visible” size.
+Note that what is and isn’t visible depends on where the text is displayed.
+
+## Examples
+
+### Example: `stringLength`
+
+It’s possible to align tables based on the visual width of cells.
+First, let’s show the problem:
+
+```js
+import {fromMarkdown} from 'mdast-util-from-markdown'
+import {toMarkdown} from 'mdast-util-to-markdown'
+import {gfmTable} from 'micromark-extension-gfm-table'
+import {gfmTableFromMarkdown, gfmTableToMarkdown} from 'mdast-util-gfm-table'
+
+const doc = `| Alpha | Bravo |
+| - | - |
+| 中文 | Charlie |
+| 👩‍❤️‍👩 | Delta |`
+
+const tree = fromMarkdown(doc, {
+  extensions: [gfmTable],
+  mdastExtensions: [gfmTableFromMarkdown]
+})
+
+console.log(toMarkdown(tree, {extensions: [gfmTableToMarkdown()]}))
+```
+
+The above code shows how these utilities can be used to format markdown.
+The output is as follows:
+
+```markdown
+| Alpha    | Bravo   |
+| -------- | ------- |
+| 中文       | Charlie |
+| 👩‍❤️‍👩 | Delta   |
+```
+
+To improve the alignment of these full-width characters and emoji, pass a
+`stringLength` function that calculates the visual width of cells.
+One such algorithm is [`string-width`][string-width].
+It can be used like so:
+
+```diff
+@@ -2,6 +2,7 @@ import {fromMarkdown} from 'mdast-util-from-markdown'
+ import {toMarkdown} from 'mdast-util-to-markdown'
+ import {gfmTable} from 'micromark-extension-gfm-table'
+ import {gfmTableFromMarkdown, gfmTableToMarkdown} from 'mdast-util-gfm-table'
++import stringWidth from 'string-width'
+
+ const doc = `| Alpha | Bravo |
+ | - | - |
+@@ -13,4 +14,8 @@ const tree = fromMarkdown(doc, {
+   mdastExtensions: [gfmTableFromMarkdown]
+ })
+
+-console.log(toMarkdown(tree, {extensions: [gfmTableToMarkdown()]}))
++console.log(
++  toMarkdown(tree, {
++    extensions: [gfmTableToMarkdown({stringLength: stringWidth})]
++  })
++)
+```
+
+The output of our code with these changes is as follows:
+
+```markdown
+| Alpha | Bravo   |
+| ----- | ------- |
+| 中文  | Charlie |
+| 👩‍❤️‍👩    | Delta   |
+```
+
+## Syntax tree
+
+The following interfaces are added to **[mdast][]** by this utility.
+
+### Nodes
+
+#### `Table`
+
+```idl
+interface Table <: Parent {
+  type: "table"
+  align: [alignType]?
+  children: [TableContent]
+}
+```
+
+**Table** ([**Parent**][dfn-parent]) represents two-dimensional data.
+
+**Table** can be used where [**flow**][dfn-flow-content] content is expected.
+Its content model is [**table**][dfn-table-content] content.
+
+The [*head*][term-head] of the node represents the labels of the columns.
+
+An `align` field can be present.
+If present, it must be a list of [**alignType**s][dfn-enum-align-type].
+It represents how cells in columns are aligned.
+
+For example, the following markdown:
+
+```markdown
+| foo | bar |
+| :-- | :-: |
+| baz | qux |
+```
+
+Yields:
+
+```js
+{
+  type: 'table',
+  align: ['left', 'center'],
+  children: [
+    {
+      type: 'tableRow',
+      children: [
+        {
+          type: 'tableCell',
+          children: [{type: 'text', value: 'foo'}]
+        },
+        {
+          type: 'tableCell',
+          children: [{type: 'text', value: 'bar'}]
+        }
+      ]
+    },
+    {
+      type: 'tableRow',
+      children: [
+        {
+          type: 'tableCell',
+          children: [{type: 'text', value: 'baz'}]
+        },
+        {
+          type: 'tableCell',
+          children: [{type: 'text', value: 'qux'}]
+        }
+      ]
+    }
+  ]
+}
+```
+
+#### `TableRow`
+
+```idl
+interface TableRow <: Parent {
+  type: "tableRow"
+  children: [RowContent]
+}
+```
+
+**TableRow** ([**Parent**][dfn-parent]) represents a row of cells in a table.
+
+**TableRow** can be used where [**table**][dfn-table-content] content is
+expected.
+Its content model is [**row**][dfn-row-content] content.
+
+If the node is a [*head*][term-head], it represents the labels of the columns
+for its parent [**Table**][dfn-table].
+
+For an example, see [**Table**][dfn-table].
+
+#### `TableCell`
+
+```idl
+interface TableCell <: Parent {
+  type: "tableCell"
+  children: [PhrasingContent]
+}
+```
+
+**TableCell** ([**Parent**][dfn-parent]) represents a header cell in a
+[**Table**][dfn-table], if its parent is a [*head*][term-head], or a data
+cell otherwise.
+
+**TableCell** can be used where [**row**][dfn-row-content] content is expected.
+Its content model is [**phrasing**][dfn-phrasing-content] content excluding
+[**Break**][dfn-break] nodes.
+
+For an example, see [**Table**][dfn-table].
+
+### Enumeration
+
+#### `alignType`
+
+```idl
+enum alignType {
+  "left" | "right" | "center" | null
+}
+```
+
+**alignType** represents how phrasing content is aligned
+([\[CSSTEXT\]][css-text]).
+
+*   **`'left'`**: See the [`left`][css-left] value of the `text-align` CSS
+    property
+*   **`'right'`**: See the [`right`][css-right] value of the `text-align`
+    CSS property
+*   **`'center'`**: See the [`center`][css-center] value of the `text-align`
+    CSS property
+*   **`null`**: phrasing content is aligned as defined by the host environment
+
+### Content model
+
+#### `FlowContent` (GFM table)
+
+```idl
+type FlowContentGfm = Table | FlowContent
+```
+
+#### `TableContent`
+
+```idl
+type TableContent = TableRow
+```
+
+**Table** content represent the rows in a table.
+
+#### `RowContent`
+
+```idl
+type RowContent = TableCell
+```
+
+**Row** content represent the cells in a row.
+
+## Types
+
+This package is fully typed with [TypeScript][].
+It exports the additional type `Options`.
+
+The `Table`, `TableRow`, and `TableCell` node types are supported in
+`@types/mdast` by default.
+
+## Compatibility
+
+Projects maintained by the unified collective are compatible with all maintained
+versions of Node.js.
+As of now, that is Node.js 12.20+, 14.14+, and 16.0+.
+Our projects sometimes work with older versions, but this is not guaranteed.
+
+This plugin works with `mdast-util-from-markdown` version 1+ and
+`mdast-util-to-markdown` version 1+.
 
 ## Related
 
-*   [`remarkjs/remark`][remark]
-    — markdown processor powered by plugins
 *   [`remarkjs/remark-gfm`][remark-gfm]
     — remark plugin to support GFM
-*   [`micromark/micromark`][micromark]
-    — the smallest commonmark-compliant markdown parser that exists
+*   [`syntax-tree/mdast-util-gfm`][mdast-util-gfm]
+    — same but all of GFM (autolink literals, footnotes, strikethrough, tables,
+    tasklists)
 *   [`micromark/micromark-extension-gfm-table`][extension]
     — micromark extension to parse GFM tables
-*   [`syntax-tree/mdast-util-from-markdown`][from-markdown]
-    — mdast parser using `micromark` to create mdast from markdown
-*   [`syntax-tree/mdast-util-to-markdown`][to-markdown]
-    — mdast serializer to create markdown from mdast
 
 ## Contribute
 
-See [`contributing.md` in `syntax-tree/.github`][contributing] for ways to get
-started.
+See [`contributing.md`][contributing] in [`syntax-tree/.github`][health] for
+ways to get started.
 See [`support.md`][support] for ways to get help.
 
 This project has a [code of conduct][coc].
@@ -207,32 +497,64 @@ abide by its terms.
 
 [npm]: https://docs.npmjs.com/cli/install
 
+[esm]: https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c
+
+[esmsh]: https://esm.sh
+
+[typescript]: https://www.typescriptlang.org
+
 [license]: license
 
 [author]: https://wooorm.com
 
-[contributing]: https://github.com/syntax-tree/.github/blob/HEAD/contributing.md
+[health]: https://github.com/syntax-tree/.github
 
-[support]: https://github.com/syntax-tree/.github/blob/HEAD/support.md
+[contributing]: https://github.com/syntax-tree/.github/blob/main/contributing.md
 
-[coc]: https://github.com/syntax-tree/.github/blob/HEAD/code-of-conduct.md
-
-[mdast]: https://github.com/syntax-tree/mdast
+[support]: https://github.com/syntax-tree/.github/blob/main/support.md
 
-[remark]: https://github.com/remarkjs/remark
+[coc]: https://github.com/syntax-tree/.github/blob/main/code-of-conduct.md
 
 [remark-gfm]: https://github.com/remarkjs/remark-gfm
 
-[from-markdown]: https://github.com/syntax-tree/mdast-util-from-markdown
+[mdast]: https://github.com/syntax-tree/mdast
+
+[mdast-util-gfm]: https://github.com/syntax-tree/mdast-util-gfm
 
-[to-markdown]: https://github.com/syntax-tree/mdast-util-to-markdown
+[mdast-util-from-markdown]: https://github.com/syntax-tree/mdast-util-from-markdown
 
-[micromark]: https://github.com/micromark/micromark
+[mdast-util-to-markdown]: https://github.com/syntax-tree/mdast-util-to-markdown
+
+[mdast-util-to-hast]: https://github.com/syntax-tree/mdast-util-to-hast
 
 [extension]: https://github.com/micromark/micromark-extension-gfm-table
 
-[markdown-table]: https://github.com/wooorm/markdown-table
+[gfm]: https://github.github.com/gfm/
 
-[string-length]: https://github.com/wooorm/markdown-table#optionsstringlength
+[string-width]: https://github.com/sindresorhus/string-width
 
-[mdast-util-gfm]: https://github.com/syntax-tree/mdast-util-gfm
+[css-text]: https://drafts.csswg.org/css-text/
+
+[css-left]: https://drafts.csswg.org/css-text/#valdef-text-align-left
+
+[css-right]: https://drafts.csswg.org/css-text/#valdef-text-align-right
+
+[css-center]: https://drafts.csswg.org/css-text/#valdef-text-align-center
+
+[term-head]: https://github.com/syntax-tree/unist#head
+
+[dfn-parent]: https://github.com/syntax-tree/mdast#parent
+
+[dfn-phrasing-content]: https://github.com/syntax-tree/mdast#phrasingcontent
+
+[dfn-break]: https://github.com/syntax-tree/mdast#break
+
+[dfn-flow-content]: #flowcontent-gfm-table
+
+[dfn-table-content]: #tablecontent
+
+[dfn-enum-align-type]: #aligntype
+
+[dfn-row-content]: #rowcontent
+
+[dfn-table]: #table