diff --git a/.editorconfig b/.editorconfig
deleted file mode 100644
index c6c8b36..0000000
--- a/.editorconfig
+++ /dev/null
@@ -1,9 +0,0 @@
-root = true
-
-[*]
-indent_style = space
-indent_size = 2
-end_of_line = lf
-charset = utf-8
-trim_trailing_whitespace = true
-insert_final_newline = true
diff --git a/.github/workflows/bb.yml b/.github/workflows/bb.yml
deleted file mode 100644
index 0198fc3..0000000
--- a/.github/workflows/bb.yml
+++ /dev/null
@@ -1,13 +0,0 @@
-name: bb
-on:
-  issues:
-    types: [opened, reopened, edited, closed, labeled, unlabeled]
-  pull_request_target:
-    types: [opened, reopened, edited, closed, labeled, unlabeled]
-jobs:
-  main:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: unifiedjs/beep-boop-beta@main
-        with:
-          repo-token: ${{secrets.GITHUB_TOKEN}}
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
deleted file mode 100644
index fe284ad..0000000
--- a/.github/workflows/main.yml
+++ /dev/null
@@ -1,21 +0,0 @@
-name: main
-on:
-  - pull_request
-  - push
-jobs:
-  main:
-    name: ${{matrix.node}}
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - uses: dcodeIO/setup-node-nvm@master
-        with:
-          node-version: ${{matrix.node}}
-      - run: npm install
-      - run: npm test
-      - uses: codecov/codecov-action@v1
-    strategy:
-      matrix:
-        node:
-          - lts/erbium
-          - node
diff --git a/.gitignore b/.gitignore
deleted file mode 100644
index 53a29e3..0000000
--- a/.gitignore
+++ /dev/null
@@ -1,6 +0,0 @@
-coverage/
-node_modules/
-.DS_Store
-*.d.ts
-*.log
-yarn.lock
diff --git a/.npmrc b/.npmrc
deleted file mode 100644
index 43c97e7..0000000
--- a/.npmrc
+++ /dev/null
@@ -1 +0,0 @@
-package-lock=false
diff --git a/.prettierignore b/.prettierignore
deleted file mode 100644
index e7939c4..0000000
--- a/.prettierignore
+++ /dev/null
@@ -1,3 +0,0 @@
-coverage/
-*.json
-*.md
diff --git a/index.js b/index.js
deleted file mode 100644
index de75166..0000000
--- a/index.js
+++ /dev/null
@@ -1,101 +0,0 @@
-/**
- * @typedef {import('mdast').Root} Root
- * @typedef {import('hast').Properties} Properties
- * @typedef {import('hast').Element['children'][number]} ElementChild
- *
- * @typedef Options
- *   Configuration.
- * @property {'_self'|'_blank'|'_parent'|'_top'|false} [target='_blank']
- *   How to display referenced documents (`string?`: `_self`, `_blank`,
- *   `_parent`, or `_top`, default: `_blank`).
- *   Pass `false` to not set `target`s on links.
- * @property {string[]|string|false} [rel=['nofollow', 'noopener', 'noreferrer']]
- *   Link types to hint about the referenced documents.
- *   Pass `false` to not set `rel`s on links.
- *
- *   > When using a `target`, add `noopener` and `noreferrer` to avoid
- *   > exploitation of the `window.opener` API.
- * @property {string[]} [protocols=['http', 'https']]
- *   Protocols to check, such as `mailto` or `tel`.
- * @property {ElementChild|ElementChild[]} [content]
- *   hast content to insert at the end of external links.
- *   Will be inserted in a `<span>` element.
- *
- *   Useful for improving accessibility by [giving users advanced warning when
- *   opening a new window.
- * @property {Properties} [contentProperties]
- *   `Properties` to add to the `span` wrapping `content`, when given.
- */
-
-import {visit} from 'unist-util-visit'
-import {definitions} from 'mdast-util-definitions'
-import {parse} from 'space-separated-tokens'
-import absolute from 'is-absolute-url'
-import extend from 'extend'
-
-const defaultTarget = '_blank'
-const defaultRel = ['nofollow', 'noopener', 'noreferrer']
-const defaultProtocols = ['http', 'https']
-
-/**
- * Plugin to automatically add `target` and `rel` attributes to external links.
- *
- * @type {import('unified').Plugin<[Options?]|void[], Root>}
- */
-export default function remarkExternalLinks(options = {}) {
-  const target = options.target
-  const rel = typeof options.rel === 'string' ? parse(options.rel) : options.rel
-  const protocols = options.protocols || defaultProtocols
-  const content =
-    options.content && !Array.isArray(options.content)
-      ? [options.content]
-      : options.content
-  const contentProperties = options.contentProperties || {}
-
-  return (tree) => {
-    const definition = definitions(tree)
-
-    visit(tree, (node) => {
-      if (node.type === 'link' || node.type === 'linkReference') {
-        const ctx = node.type === 'link' ? node : definition(node.identifier)
-
-        // Undefined references can be injected into the tree by plugins.
-        /* c8 ignore next */
-        if (!ctx) return
-
-        const protocol = ctx.url.slice(0, ctx.url.indexOf(':'))
-
-        if (absolute(ctx.url) && protocols.includes(protocol)) {
-          const data = node.data || (node.data = {})
-          const props = /** @type {Properties} */ (
-            data.hProperties || (data.hProperties = {})
-          )
-
-          if (target !== false) {
-            props.target = target || defaultTarget
-          }
-
-          if (rel !== false) {
-            props.rel = (rel || defaultRel).concat()
-          }
-
-          if (content) {
-            // `fragment` is not a known mdast node, but unknown nodes with
-            // children are handled as elements by `mdast-util-to-hast`:
-            // See: <https://github.com/syntax-tree/mdast-util-to-hast#notes>.
-            node.children.push({
-              // @ts-expect-error
-              type: 'fragment',
-              children: [],
-              data: {
-                hName: 'span',
-                hProperties: extend(true, contentProperties),
-                hChildren: extend(true, content)
-              }
-            })
-          }
-        }
-      }
-    })
-  }
-}
diff --git a/license b/license
deleted file mode 100644
index aa0cee1..0000000
--- a/license
+++ /dev/null
@@ -1,22 +0,0 @@
-(The MIT License)
-
-Copyright (c) 2017 Cédric Delpoux <xuopled@gmail.com>
-
-Permission is hereby granted, free of charge, to any person obtaining
-a copy of this software and associated documentation files (the
-'Software'), to deal in the Software without restriction, including
-without limitation the rights to use, copy, modify, merge, publish,
-distribute, sublicense, and/or sell copies of the Software, and to
-permit persons to whom the Software is furnished to do so, subject to
-the following conditions:
-
-The above copyright notice and this permission notice shall be
-included in all copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND,
-EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
-IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
-CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
-TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
-SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
diff --git a/package.json b/package.json
index 4d7b30a..f102b75 100644
--- a/package.json
+++ b/package.json
@@ -1,85 +1,6 @@
 {
+  "bugs": "https://github.com/remarkjs/remark-external-links/issues",
   "name": "remark-external-links",
-  "version": "9.0.1",
-  "description": "Legacy remark plugin to automatically add target and rel attributes to external links — please use `rehype-external-links`",
-  "license": "MIT",
-  "keywords": [],
   "repository": "remarkjs/remark-external-links",
-  "bugs": "https://github.com/remarkjs/remark-external-links/issues",
-  "funding": {
-    "type": "opencollective",
-    "url": "https://opencollective.com/unified"
-  },
-  "author": "Cédric Delpoux <xuopled@gmail.com>",
-  "contributors": [
-    "Cédric Delpoux <xuopled@gmail.com>",
-    "Titus Wormer <tituswormer@gmail.com> (https://wooorm.com)",
-    "Merlijn Vos <merlijn@soverin.net>",
-    "Takayosi Amagi <fand.gmork@gmail.com>",
-    "Zach Schnackel <info@zslabs.com>",
-    "Tsuyusato Kitsune <make.just.on@gmail.com>",
-    "Matsuko Friedland <info@matsuko.ca>"
-  ],
-  "sideEffects": false,
-  "type": "module",
-  "main": "index.js",
-  "types": "index.d.ts",
-  "files": [
-    "index.d.ts",
-    "index.js"
-  ],
-  "dependencies": {
-    "@types/hast": "^2.3.2",
-    "@types/mdast": "^3.0.0",
-    "extend": "^3.0.0",
-    "is-absolute-url": "^4.0.0",
-    "mdast-util-definitions": "^5.0.0",
-    "space-separated-tokens": "^2.0.0",
-    "unified": "^10.0.0",
-    "unist-util-visit": "^4.0.0"
-  },
-  "devDependencies": {
-    "@types/extend": "^3.0.1",
-    "@types/tape": "^4.0.0",
-    "c8": "^7.0.0",
-    "prettier": "^2.0.0",
-    "remark": "^14.0.0",
-    "remark-cli": "^10.0.0",
-    "remark-html": "^14.0.0",
-    "remark-preset-wooorm": "^9.0.0",
-    "rimraf": "^3.0.0",
-    "tape": "^5.0.0",
-    "type-coverage": "^2.0.0",
-    "typescript": "^4.0.0",
-    "xo": "^0.44.0"
-  },
-  "scripts": {
-    "build": "rimraf \"*.d.ts\" && tsc && type-coverage",
-    "format": "remark . -qfo && prettier . -w --loglevel warn && xo --fix",
-    "test-api": "node --conditions development test.js",
-    "test-coverage": "c8 --check-coverage --branches 100 --functions 100 --lines 100 --statements 100 --reporter lcov npm run test-api",
-    "test": "npm run build && npm run format && npm run test-coverage"
-  },
-  "prettier": {
-    "tabWidth": 2,
-    "useTabs": false,
-    "singleQuote": true,
-    "bracketSpacing": false,
-    "semi": false,
-    "trailingComma": "none"
-  },
-  "xo": {
-    "prettier": true
-  },
-  "remarkConfig": {
-    "plugins": [
-      "preset-wooorm"
-    ]
-  },
-  "typeCoverage": {
-    "atLeast": 100,
-    "detail": true,
-    "strict": true,
-    "ignoreCatch": true
-  }
+  "version": "10.0.0"
 }
diff --git a/readme.md b/readme.md
index 5ef8030..08d3c09 100644
--- a/readme.md
+++ b/readme.md
@@ -1,24 +1,12 @@
 # remark-external-links
 
-**Stability: Legacy**.
-This package is no longer recommended for use.
-It’s still covered by semantic-versioning guarantees and not yet deprecated,
-but use of this package should be avoided.
+Deprecated: this package is no longer maintained.
 Please use `remark-rehype` to move from remark (markdown) to rehype (HTML)
 and then replace `remark-external-links` with
 [`rehype-external-links`][rehype-external-links].
 
-Legacy [documentation for this package](https://github.com/remarkjs/remark-external-links/tree/307f8dc)
-is still available in Git.
+[Git][] is still intact and previous versions can still be used without warnings.
 
-## License
-
-[MIT][license] © [Cédric Delpoux][author]
-
-<!-- Definitions -->
-
-[license]: license
-
-[author]: https://xuopled.netlify.com
+[git]: https://github.com/remarkjs/remark-external-links/tree/11bfaea
 
 [rehype-external-links]: https://github.com/rehypejs/rehype-external-links
diff --git a/test.js b/test.js
deleted file mode 100644
index 0fee1f4..0000000
--- a/test.js
+++ /dev/null
@@ -1,184 +0,0 @@
-import test from 'tape'
-import {remark} from 'remark'
-import html from 'remark-html'
-import externalLinks from './index.js'
-
-const input = [
-  '[remark](https://github.com/remarkjs/remark)',
-  '',
-  '[relative link](./example.md) and [fragment link](#fragment)',
-  '',
-  '[missing][], [local][], and [external][].',
-  '',
-  '[current](.) [up](..) [relative link without ./](example.md)',
-  '',
-  '[local]: #local',
-  '[external]: https://github.com/remarkjs/remark',
-  '',
-  '<test@example.com>'
-].join('\n')
-
-test('remark-external-links', (t) => {
-  t.equal(
-    remark().use(externalLinks).use(html).processSync(input).toString(),
-    [
-      '<p><a href="https://github.com/remarkjs/remark" target="_blank" rel="nofollow noopener noreferrer">remark</a></p>',
-      '<p><a href="./example.md">relative link</a> and <a href="#fragment">fragment link</a></p>',
-      '<p>[missing][], <a href="#local">local</a>, and <a href="https://github.com/remarkjs/remark" target="_blank" rel="nofollow noopener noreferrer">external</a>.</p>',
-      '<p><a href=".">current</a> <a href="..">up</a> <a href="example.md">relative link without ./</a></p>',
-      '<p><a href="mailto:test@example.com">test@example.com</a></p>',
-      ''
-    ].join('\n'),
-    'should add the defaults when without options'
-  )
-
-  t.equal(
-    remark()
-      .use(externalLinks, {target: false, rel: false})
-      .use(html)
-      .processSync(input)
-      .toString(),
-    [
-      '<p><a href="https://github.com/remarkjs/remark">remark</a></p>',
-      '<p><a href="./example.md">relative link</a> and <a href="#fragment">fragment link</a></p>',
-      '<p>[missing][], <a href="#local">local</a>, and <a href="https://github.com/remarkjs/remark">external</a>.</p>',
-      '<p><a href=".">current</a> <a href="..">up</a> <a href="example.md">relative link without ./</a></p>',
-      '<p><a href="mailto:test@example.com">test@example.com</a></p>',
-      ''
-    ].join('\n'),
-    'should do nothing if both are set to false'
-  )
-
-  t.equal(
-    remark()
-      .use(externalLinks, {target: '_blank', rel: false})
-      .use(html)
-      .processSync(input)
-      .toString(),
-    [
-      '<p><a href="https://github.com/remarkjs/remark" target="_blank">remark</a></p>',
-      '<p><a href="./example.md">relative link</a> and <a href="#fragment">fragment link</a></p>',
-      '<p>[missing][], <a href="#local">local</a>, and <a href="https://github.com/remarkjs/remark" target="_blank">external</a>.</p>',
-      '<p><a href=".">current</a> <a href="..">up</a> <a href="example.md">relative link without ./</a></p>',
-      '<p><a href="mailto:test@example.com">test@example.com</a></p>',
-      ''
-    ].join('\n'),
-    'should add a target'
-  )
-
-  t.equal(
-    remark()
-      .use(externalLinks, {target: false, rel: 'nofollow'})
-      .use(html)
-      .processSync(input)
-      .toString(),
-    [
-      '<p><a href="https://github.com/remarkjs/remark" rel="nofollow">remark</a></p>',
-      '<p><a href="./example.md">relative link</a> and <a href="#fragment">fragment link</a></p>',
-      '<p>[missing][], <a href="#local">local</a>, and <a href="https://github.com/remarkjs/remark" rel="nofollow">external</a>.</p>',
-      '<p><a href=".">current</a> <a href="..">up</a> <a href="example.md">relative link without ./</a></p>',
-      '<p><a href="mailto:test@example.com">test@example.com</a></p>',
-      ''
-    ].join('\n'),
-    'should add a rel'
-  )
-
-  t.equal(
-    remark()
-      .use(externalLinks, {target: '_blank', rel: 'nofollow'})
-      .use(html)
-      .processSync(input)
-      .toString(),
-    [
-      '<p><a href="https://github.com/remarkjs/remark" target="_blank" rel="nofollow">remark</a></p>',
-      '<p><a href="./example.md">relative link</a> and <a href="#fragment">fragment link</a></p>',
-      '<p>[missing][], <a href="#local">local</a>, and <a href="https://github.com/remarkjs/remark" target="_blank" rel="nofollow">external</a>.</p>',
-      '<p><a href=".">current</a> <a href="..">up</a> <a href="example.md">relative link without ./</a></p>',
-      '<p><a href="mailto:test@example.com">test@example.com</a></p>',
-      ''
-    ].join('\n'),
-    'should add both'
-  )
-
-  t.equal(
-    remark()
-      .use(externalLinks, {protocols: ['http', 'https', 'mailto']})
-      .use(html)
-      .processSync(input)
-      .toString(),
-    [
-      '<p><a href="https://github.com/remarkjs/remark" target="_blank" rel="nofollow noopener noreferrer">remark</a></p>',
-      '<p><a href="./example.md">relative link</a> and <a href="#fragment">fragment link</a></p>',
-      '<p>[missing][], <a href="#local">local</a>, and <a href="https://github.com/remarkjs/remark" target="_blank" rel="nofollow noopener noreferrer">external</a>.</p>',
-      '<p><a href=".">current</a> <a href="..">up</a> <a href="example.md">relative link without ./</a></p>',
-      '<p><a href="mailto:test@example.com" target="_blank" rel="nofollow noopener noreferrer">test@example.com</a></p>',
-      ''
-    ].join('\n'),
-    'should add a target'
-  )
-
-  t.equal(
-    remark()
-      .use(externalLinks, {
-        content: {type: 'text', value: ' (opens in a new window)'}
-      })
-      .use(html)
-      .processSync(input)
-      .toString(),
-    [
-      '<p><a href="https://github.com/remarkjs/remark" target="_blank" rel="nofollow noopener noreferrer">remark<span> (opens in a new window)</span></a></p>',
-      '<p><a href="./example.md">relative link</a> and <a href="#fragment">fragment link</a></p>',
-      '<p>[missing][], <a href="#local">local</a>, and <a href="https://github.com/remarkjs/remark" target="_blank" rel="nofollow noopener noreferrer">external<span> (opens in a new window)</span></a>.</p>',
-      '<p><a href=".">current</a> <a href="..">up</a> <a href="example.md">relative link without ./</a></p>',
-      '<p><a href="mailto:test@example.com">test@example.com</a></p>',
-      ''
-    ].join('\n'),
-    'should add hast node as content'
-  )
-
-  t.equal(
-    remark()
-      .use(externalLinks, {
-        content: [
-          {type: 'text', value: ' ('},
-          {
-            type: 'element',
-            tagName: 'em',
-            properties: {},
-            children: [{type: 'text', value: 'opens in a new window'}]
-          },
-          {type: 'text', value: ')'}
-        ]
-      })
-      .use(html)
-      .processSync(input)
-      .toString(),
-    [
-      '<p><a href="https://github.com/remarkjs/remark" target="_blank" rel="nofollow noopener noreferrer">remark<span> (<em>opens in a new window</em>)</span></a></p>',
-      '<p><a href="./example.md">relative link</a> and <a href="#fragment">fragment link</a></p>',
-      '<p>[missing][], <a href="#local">local</a>, and <a href="https://github.com/remarkjs/remark" target="_blank" rel="nofollow noopener noreferrer">external<span> (<em>opens in a new window</em>)</span></a>.</p>',
-      '<p><a href=".">current</a> <a href="..">up</a> <a href="example.md">relative link without ./</a></p>',
-      '<p><a href="mailto:test@example.com">test@example.com</a></p>',
-      ''
-    ].join('\n'),
-    'should add hast children as content'
-  )
-
-  t.equal(
-    remark()
-      .use(externalLinks, {
-        contentProperties: {className: ['alpha', 'bravo']},
-        content: {type: 'text', value: ' (opens in a new window)'}
-      })
-      .use(html)
-      .processSync('[a](https://example.com)')
-      .toString(),
-    [
-      '<p><a href="https://example.com" target="_blank" rel="nofollow noopener noreferrer">a<span class="alpha bravo"> (opens in a new window)</span></a></p>',
-      ''
-    ].join('\n'),
-    'should support `contentProperties`'
-  )
-
-  t.end()
-})
diff --git a/tsconfig.json b/tsconfig.json
deleted file mode 100644
index e31adf8..0000000
--- a/tsconfig.json
+++ /dev/null
@@ -1,16 +0,0 @@
-{
-  "include": ["*.js"],
-  "compilerOptions": {
-    "target": "ES2020",
-    "lib": ["ES2020"],
-    "module": "ES2020",
-    "moduleResolution": "node",
-    "allowJs": true,
-    "checkJs": true,
-    "declaration": true,
-    "emitDeclarationOnly": true,
-    "allowSyntheticDefaultImports": true,
-    "skipLibCheck": true,
-    "strict": true
-  }
-}