diff --git a/.github/ISSUE_TEMPLATE/bug-report.yml b/.github/ISSUE_TEMPLATE/bug-report.yml
index 8b2be7f8..f3015a40 100644
--- a/.github/ISSUE_TEMPLATE/bug-report.yml
+++ b/.github/ISSUE_TEMPLATE/bug-report.yml
@@ -13,6 +13,8 @@ body:
                 required: false
               - label: "`eslint-scope`"
                 required: false
+              - label: "`eslint-visitor-keys`"
+                required: false
     - type: textarea
       attributes:
           label: Environment
diff --git a/.github/ISSUE_TEMPLATE/change.yml b/.github/ISSUE_TEMPLATE/change.yml
index fb658fa9..3ad2bd5b 100644
--- a/.github/ISSUE_TEMPLATE/change.yml
+++ b/.github/ISSUE_TEMPLATE/change.yml
@@ -12,6 +12,8 @@ body:
                 required: false
               - label: "`eslint-scope`"
                 required: false
+              - label: "`eslint-visitor-keys`"
+                required: false
     - type: textarea
       attributes:
           label: What problem do you want to solve?
diff --git a/.github/ISSUE_TEMPLATE/docs.yml b/.github/ISSUE_TEMPLATE/docs.yml
index a5f6954f..45aef633 100644
--- a/.github/ISSUE_TEMPLATE/docs.yml
+++ b/.github/ISSUE_TEMPLATE/docs.yml
@@ -12,6 +12,8 @@ body:
                 required: false
               - label: "`eslint-scope`"
                 required: false
+              - label: "`eslint-visitor-keys`"
+                required: false
     - type: textarea
       attributes:
           label: What documentation issue do you want to solve?
diff --git a/.github/workflows/release-please.yml b/.github/workflows/release-please.yml
index 518537bb..fa6bf7af 100644
--- a/.github/workflows/release-please.yml
+++ b/.github/workflows/release-please.yml
@@ -46,6 +46,32 @@ jobs:
           # fewest internal dependencies are released first and the packages with the
           # most internal dependencies are released last.
           #-----------------------------------------------------------------------------
+          
+          #-----------------------------------------------------------------------------
+          # eslint-visitor-keys
+          #-----------------------------------------------------------------------------
+
+          - name: Publish eslint-visitor-keys package to npm
+            run: npm publish -w packages/eslint-visitor-keys --provenance
+            if: ${{ steps.release.outputs['packages/eslint-visitor-keys--release_created'] }}
+            env:
+                NODE_AUTH_TOKEN: ${{secrets.NPM_TOKEN}}
+
+          - name: Tweet Release Announcement
+            run: npx @humanwhocodes/tweet "eslint-visitor-keys v${{ steps.release.outputs['packages/eslint-visitor-keys--major'] }}.${{ steps.release.outputs['packages/eslint-visitor-keys--minor'] }}.${{ steps.release.outputs['packages/eslint-visitor-keys--patch'] }} has been released!\n\n${{ github.event.repository.html_url }}/releases/tag/${{ steps.release.outputs['packages/eslint-visitor-keys--tag_name'] }}"
+            if: ${{ steps.release.outputs['packages/eslint-visitor-keys--release_created'] }}
+            env:
+                TWITTER_CONSUMER_KEY: ${{ secrets.TWITTER_CONSUMER_KEY }}
+                TWITTER_CONSUMER_SECRET: ${{ secrets.TWITTER_CONSUMER_SECRET }}
+                TWITTER_ACCESS_TOKEN_KEY: ${{ secrets.TWITTER_ACCESS_TOKEN_KEY }}
+                TWITTER_ACCESS_TOKEN_SECRET: ${{ secrets.TWITTER_ACCESS_TOKEN_SECRET }}
+
+          - name: Toot Release Announcement
+            run: npx @humanwhocodes/toot "eslint-visitor-keys v${{ steps.release.outputs['packages/eslint-visitor-keys--major'] }}.${{ steps.release.outputs['packages/eslint-visitor-keys--minor'] }}.${{ steps.release.outputs['packages/eslint-visitor-keys--patch'] }} has been released!\n\n${{ github.event.repository.html_url }}/releases/tag/${{ steps.release.outputs['packages/eslint-visitor-keys--tag_name'] }}"
+            if: ${{ steps.release.outputs['packages/eslint-visitor-keys--release_created'] }}
+            env:
+                MASTODON_ACCESS_TOKEN: ${{ secrets.MASTODON_ACCESS_TOKEN }}
+                MASTODON_HOST: ${{ secrets.MASTODON_HOST }}
 
           #-----------------------------------------------------------------------------
           # espree
diff --git a/.release-please-manifest.json b/.release-please-manifest.json
index 629fd483..f5d4e6f3 100644
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,4 +1,5 @@
 {
     "packages/espree": "10.1.0",
-    "packages/eslint-scope": "8.0.2"
+    "packages/eslint-scope": "8.0.2",
+    "packages/eslint-visitor-keys": "4.0.0"
 }
diff --git a/README.md b/README.md
index fef29aee..3d45d23b 100644
--- a/README.md
+++ b/README.md
@@ -8,6 +8,7 @@ This repository is the home of the following packages:
 
 - [`espree`](packages/espree)
 - [`eslint-scope`](packages/eslint-scope)
+- [`eslint-visitor-keys`](packages/eslint-visitor-keys)
 
 ## Security Policy
 
diff --git a/eslint.config.js b/eslint.config.js
index 63018ca0..9cc3bc37 100644
--- a/eslint.config.js
+++ b/eslint.config.js
@@ -15,7 +15,7 @@ export default [
     ...eslintConfigESLint,
     eslintConfigESLintFormatting,
     {
-        files: ["packages/espree/tests/lib/**"],
+        files: ["packages/*/tests/lib/**"],
         languageOptions: {
             globals: {
                 ...globals.mocha
@@ -55,6 +55,20 @@ export default [
             "no-console": "off"
         }
     },
+    {
+        files: ["packages/eslint-scope/**"],
+        linterOptions: {
+            reportUnusedDisableDirectives: "error"
+        },
+        settings: {
+            jsdoc: {
+                preferredTypes: {
+                    Object: "object",
+                    "object<>": "Object"
+                }
+            }
+        }
+    },
     {
         files: ["**/tools/**"],
         rules: {
diff --git a/packages/eslint-visitor-keys/CHANGELOG.md b/packages/eslint-visitor-keys/CHANGELOG.md
new file mode 100644
index 00000000..a150f8aa
--- /dev/null
+++ b/packages/eslint-visitor-keys/CHANGELOG.md
@@ -0,0 +1,124 @@
+# Changelog
+
+## [4.0.0](https://github.com/eslint/eslint-visitor-keys/compare/v3.4.3...v4.0.0) (2024-02-08)
+
+
+### ⚠ BREAKING CHANGES
+
+* Require Node.js `^18.18.0 || ^20.9.0 || >=21.1.0` ([#63](https://github.com/eslint/eslint-visitor-keys/issues/63))
+
+### Features
+
+* Require Node.js `^18.18.0 || ^20.9.0 || >=21.1.0` ([#63](https://github.com/eslint/eslint-visitor-keys/issues/63)) ([388b2ac](https://github.com/eslint/eslint-visitor-keys/commit/388b2acedbe3881edd52b45f217db393731feb48))
+
+
+### Chores
+
+* run tests in Node.js 21 ([#61](https://github.com/eslint/eslint-visitor-keys/issues/61)) ([b23bfb7](https://github.com/eslint/eslint-visitor-keys/commit/b23bfb7f938d6559dfff8f02203c866a2fb26618))
+
+## [3.4.3](https://github.com/eslint/eslint-visitor-keys/compare/v3.4.2...v3.4.3) (2023-08-08)
+
+
+### Chores
+
+* Add back add-to-triage ([#59](https://github.com/eslint/eslint-visitor-keys/issues/59)) ([5ea8b12](https://github.com/eslint/eslint-visitor-keys/commit/5ea8b120d73f1dd6db92427d025c6805df43397d))
+* Remove add-to-triage ([#56](https://github.com/eslint/eslint-visitor-keys/issues/56)) ([45d4c17](https://github.com/eslint/eslint-visitor-keys/commit/45d4c17b63d26ef486c92cfb60283991e36d6db0))
+* standardize npm script names ([#55](https://github.com/eslint/eslint-visitor-keys/issues/55)) ([0461695](https://github.com/eslint/eslint-visitor-keys/commit/0461695b730821c04c20d46f5cff9195509f865b))
+* update `typedef` in build keys template ([#58](https://github.com/eslint/eslint-visitor-keys/issues/58)) ([eb6c66d](https://github.com/eslint/eslint-visitor-keys/commit/eb6c66dbaf6389d253d10dd74d22915d7e33d651))
+
+## [3.4.2](https://github.com/eslint/eslint-visitor-keys/compare/v3.4.1...v3.4.2) (2023-07-27)
+
+
+### Documentation
+
+* fix spelling mistakes ([#50](https://github.com/eslint/eslint-visitor-keys/issues/50)) ([4ce1c17](https://github.com/eslint/eslint-visitor-keys/commit/4ce1c1777181b87f5dcd3f10a3d8aef0710f8d0e))
+* remove `release` script reference from README ([#52](https://github.com/eslint/eslint-visitor-keys/issues/52)) ([4640146](https://github.com/eslint/eslint-visitor-keys/commit/46401465ff5bb08bf793219d399c11434fd163be))
+
+
+### Chores
+
+* Add PRs to triage ([#54](https://github.com/eslint/eslint-visitor-keys/issues/54)) ([a7b64b4](https://github.com/eslint/eslint-visitor-keys/commit/a7b64b4ea0a4548f92cb41428d3e23b30f0cf8de))
+* generate provenance statements when release ([#53](https://github.com/eslint/eslint-visitor-keys/issues/53)) ([7b09698](https://github.com/eslint/eslint-visitor-keys/commit/7b09698fa51bbd9fcace50cb1014eec87abde140))
+
+## [3.4.1](https://github.com/eslint/eslint-visitor-keys/compare/v3.4.0...v3.4.1) (2023-05-05)
+
+
+### Bug Fixes
+
+* correct types for node16 resolution ([#47](https://github.com/eslint/eslint-visitor-keys/issues/47)) ([7bd1fc1](https://github.com/eslint/eslint-visitor-keys/commit/7bd1fc1d483c2d0fdd5e0eddb2702f177372889c))
+
+
+### Chores
+
+* run tests on Node.js v20 ([#45](https://github.com/eslint/eslint-visitor-keys/issues/45)) ([c982093](https://github.com/eslint/eslint-visitor-keys/commit/c982093329f12c02dc87569930a6042f4095026b))
+* set up release-please ([#48](https://github.com/eslint/eslint-visitor-keys/issues/48)) ([a7fb4c7](https://github.com/eslint/eslint-visitor-keys/commit/a7fb4c7eb5d122e89bc6c24779ea06c487242c87))
+
+v3.4.0 - March 27, 2023
+
+* [`e9a070f`](https://github.com/eslint/eslint-visitor-keys/commit/e9a070fcbf53c14374e17801799016ce21d0c0ff) fix: remove useless sourcemap url (fixes #43) (#44) (余腾靖)
+* [`0398109`](https://github.com/eslint/eslint-visitor-keys/commit/0398109f1f751c58be3bd3206d22ae9c1b269219) chore: add triage action (#42) (Milos Djermanovic)
+* [`bcffbe5`](https://github.com/eslint/eslint-visitor-keys/commit/bcffbe52989bf726475c6b86eba3003275317f45) ci: add Node v19 (#41) (Milos Djermanovic)
+* [`c24f2e4`](https://github.com/eslint/eslint-visitor-keys/commit/c24f2e45cc59dbdeb8c2b48782d3599fbef9cbcb) chore: update github actions and add funding field (#40) (Deepshika S)
+* [`81c0732`](https://github.com/eslint/eslint-visitor-keys/commit/81c0732aa4086ad75f0adf4512823e4c8c584493) build: add node v18 (#39) (唯然)
+* [`6ece4bd`](https://github.com/eslint/eslint-visitor-keys/commit/6ece4bd4086965bdaf92d95b6a03d8d122468b4e) feat: add `JSXSpreadChild` and tool to build keys out of AST definitions (#36) (Brett Zamir)
+* [`4beb7a7`](https://github.com/eslint/eslint-visitor-keys/commit/4beb7a7be5fd7d25e5572c3dfee3e127edd8cadb) docs: update badges (#37) (Milos Djermanovic)
+
+v3.3.0 - February 11, 2022
+
+* [`7f10327`](https://github.com/eslint/eslint-visitor-keys/commit/7f103276844fb131cfad115ee78eb19f798d5fc8) feat: Bundle JSDoc-built TypeScript declaration file (#34) (Brett Zamir)
+
+v3.2.0 - January 15, 2022
+
+* [`5c53218`](https://github.com/eslint/eslint-visitor-keys/commit/5c532184e05440d3c883b3d7864f84eb1b11dc90) feat: add missing JSXOpeningFragment and JSXClosingFragment (#33) (Richard Huang)
+* [`2a5c9a6`](https://github.com/eslint/eslint-visitor-keys/commit/2a5c9a622d8cb09df9d40a320d146b0941081e11) docs: readme add syntax highlighting (#32) (coderaiser)
+
+v3.1.0 - November 8, 2021
+
+* [`5e3e687`](https://github.com/eslint/eslint-visitor-keys/commit/5e3e68779560a1b2edef7923d30165396bce9602) build: upgrade eslint-release to v3.2.0 to support conventional commits (#31) (Milos Djermanovic)
+* [`53d3939`](https://github.com/eslint/eslint-visitor-keys/commit/53d39390d3560c179cffd08638b50343b0841a30) Build: add node v17 (#30) (唯然)
+* [`5f5b232`](https://github.com/eslint/eslint-visitor-keys/commit/5f5b232386bd7e217dd61d08aa27c3a1e2a4665e) Update: add StaticBlock (#29) (Milos Djermanovic)
+* [`e89bff9`](https://github.com/eslint/eslint-visitor-keys/commit/e89bff9fd6a5929b1e8f4d5f9cedec45aa966074) Chore: use actions/setup-node@v2 (薛定谔的猫)
+* [`7b756cd`](https://github.com/eslint/eslint-visitor-keys/commit/7b756cd37cd28089dfee6015c001fd860e21aead) Docs: Update the minimum Node.js version requirement (#26) (0uep)
+
+v3.0.0 - June 24, 2021
+
+* [`701b67d`](https://github.com/eslint/eslint-visitor-keys/commit/701b67de7216cabebc03e7c6205fe47ce3177aa3) Breaking: drop node v10/v13/v15 (refs eslint/eslint#14023) (#23) (薛定谔的猫)
+* [`f584b12`](https://github.com/eslint/eslint-visitor-keys/commit/f584b121421ceb6c4e034b79943f3c32aaa0541d) Breaking: Switch to ESM (#24) (Brett Zamir)
+* [`7279e73`](https://github.com/eslint/eslint-visitor-keys/commit/7279e7304e95030a854408191b8fde3c01876451) Build: Update branch reference in CI (#25) (Milos Djermanovic)
+* [`c6846d6`](https://github.com/eslint/eslint-visitor-keys/commit/c6846d69271c73041b797b7de9c8254dcf439a2e) Upgrade: eslint-release (#21) (Nicholas C. Zakas)
+
+v2.1.0 - May 3, 2021
+
+* [`908fdf8`](https://github.com/eslint/eslint-visitor-keys/commit/908fdf8c0d9a352c696c8c1f4901280d1a0795f7) Update: add PrivateIdentifier and PropertyDefinition (#20) (Toru Nagashima)
+* [`2d7be11`](https://github.com/eslint/eslint-visitor-keys/commit/2d7be11e4d13ac702c9fe3c529cadbd75b370146) Chore: No longer test in Node.js 13 (#17) (Michaël De Boey)
+* [`b41b509`](https://github.com/eslint/eslint-visitor-keys/commit/b41b509b153ecd8d47af46a421122f64e93d4c67) Docs: Update required Node.js version (#15) (Michaël De Boey)
+
+v2.0.0 - August 14, 2020
+
+* [`fb86ca3`](https://github.com/eslint/eslint-visitor-keys/commit/fb86ca315daafc84e23ed9005db40b0892b972a6) Breaking: drop support for Node <10 (#13) (Kai Cataldo)
+* [`69383b3`](https://github.com/eslint/eslint-visitor-keys/commit/69383b372915e33ada094880ecc6b6e8f8c7ca4e) Chore: move to GitHub Actions (#14) (Kai Cataldo)
+
+v1.3.0 - June 19, 2020
+
+* [`c92dd7f`](https://github.com/eslint/eslint-visitor-keys/commit/c92dd7ff96f0044dba12d681406a025b92b4c437) Update: add `ChainExpression` node (#12) (Toru Nagashima)
+
+v1.2.0 - June 4, 2020
+
+* [`21f28bf`](https://github.com/eslint/eslint-visitor-keys/commit/21f28bf11be5329d740a8bf6bdbcd0ef13bbf1a2) Update: added exported in exportAllDeclaration key (#10) (Anix)
+
+v1.1.0 - August 13, 2019
+
+* [`9331cc0`](https://github.com/eslint/eslint-visitor-keys/commit/9331cc09e756e65b9044c9186445a474b037fac6) Update: add ImportExpression (#8) (Toru Nagashima)
+* [`5967f58`](https://github.com/eslint/eslint-visitor-keys/commit/5967f583b04f17fba9226aaa394e45d476d2b8af) Chore: add supported Node.js versions to CI (#7) (Kai Cataldo)
+* [`6f7c60f`](https://github.com/eslint/eslint-visitor-keys/commit/6f7c60fef2ceec9f6323202df718321cec45cab0) Upgrade: eslint-release@1.0.0 (#5) (Teddy Katz)
+
+v1.0.0 - December 18, 2017
+
+* 1f6bd38 Breaking: update keys (#4) (Toru Nagashima)
+
+v0.1.0 - November 17, 2017
+
+* 17b4a88 Chore: update `repository` field in package.json (#3) (Toru Nagashima)
+* a5a026b New: eslint-visitor-keys (#1) (Toru Nagashima)
+* a1a48b8 Update: Change license to Apache 2 (#2) (Ilya Volodin)
+* 2204715 Initial commit (Toru Nagashima)
diff --git a/packages/eslint-visitor-keys/LICENSE b/packages/eslint-visitor-keys/LICENSE
new file mode 100644
index 00000000..17a25538
--- /dev/null
+++ b/packages/eslint-visitor-keys/LICENSE
@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
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+
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+
+      "You" (or "Your") shall mean an individual or Legal Entity
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+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
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+
+   Copyright contributors
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
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+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
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diff --git a/packages/eslint-visitor-keys/README.md b/packages/eslint-visitor-keys/README.md
new file mode 100644
index 00000000..fbbfeefd
--- /dev/null
+++ b/packages/eslint-visitor-keys/README.md
@@ -0,0 +1,123 @@
+# eslint-visitor-keys
+
+[![npm version](https://img.shields.io/npm/v/eslint-visitor-keys.svg)](https://www.npmjs.com/package/eslint-visitor-keys)
+[![Downloads/month](https://img.shields.io/npm/dm/eslint-visitor-keys.svg)](http://www.npmtrends.com/eslint-visitor-keys)
+[![Build Status](https://github.com/eslint/js/workflows/CI/badge.svg)](https://github.com/eslint/js/actions)
+
+Constants and utilities about visitor keys to traverse AST.
+
+## 💿 Installation
+
+Use [npm] to install.
+
+```bash
+$ npm install eslint-visitor-keys
+```
+
+### Requirements
+
+- [Node.js] `^18.18.0`, `^20.9.0`, or `>=21.1.0`
+
+
+## 📖 Usage
+
+To use in an ESM file:
+
+```js
+import * as evk from "eslint-visitor-keys"
+```
+
+To use in a CommonJS file:
+
+```js
+const evk = require("eslint-visitor-keys")
+```
+
+### evk.KEYS
+
+> type: `{ [type: string]: string[] | undefined }`
+
+Visitor keys. This keys are frozen.
+
+This is an object. Keys are the type of [ESTree] nodes. Their values are an array of property names which have child nodes.
+
+For example:
+
+```
+console.log(evk.KEYS.AssignmentExpression) // → ["left", "right"]
+```
+
+### evk.getKeys(node)
+
+> type: `(node: object) => string[]`
+
+Get the visitor keys of a given AST node.
+
+This is similar to `Object.keys(node)` of ES Standard, but some keys are excluded: `parent`, `leadingComments`, `trailingComments`, and names which start with `_`.
+
+This will be used to traverse unknown nodes.
+
+For example:
+
+```js
+const node = {
+    type: "AssignmentExpression",
+    left: { type: "Identifier", name: "foo" },
+    right: { type: "Literal", value: 0 }
+}
+console.log(evk.getKeys(node)) // → ["type", "left", "right"]
+```
+
+### evk.unionWith(additionalKeys)
+
+> type: `(additionalKeys: object) => { [type: string]: string[] | undefined }`
+
+Make the union set with `evk.KEYS` and the given keys.
+
+- The order of keys is, `additionalKeys` is at first, then `evk.KEYS` is concatenated after that.
+- It removes duplicated keys as keeping the first one.
+
+For example:
+
+```js
+console.log(evk.unionWith({
+    MethodDefinition: ["decorators"]
+})) // → { ..., MethodDefinition: ["decorators", "key", "value"], ... }
+```
+
+## 📰 Change log
+
+See [GitHub releases](https://github.com/eslint/eslint-visitor-keys/releases).
+
+## 🍻 Contributing
+
+Welcome. See [ESLint contribution guidelines](https://eslint.org/docs/developer-guide/contributing/).
+
+### Development commands
+
+- `npm test` runs tests and measures code coverage.
+- `npm run lint` checks source codes with ESLint.
+- `npm run test:open-coverage` opens the code coverage report of the previous test with your default browser.
+
+
+[npm]: https://www.npmjs.com/
+[Node.js]: https://nodejs.org/
+[ESTree]: https://github.com/estree/estree
+
+## Sponsors
+
+The following companies, organizations, and individuals support ESLint's ongoing maintenance and development. [Become a Sponsor](https://eslint.org/donate) to get your logo on our README and website.
+
+<!-- NOTE: This section is autogenerated. Do not manually edit.-->
+<!--sponsorsstart-->
+<h3>Platinum Sponsors</h3>
+<p><a href="https://automattic.com"><img src="https://images.opencollective.com/automattic/d0ef3e1/logo.png" alt="Automattic" height="128"></a> <a href="https://www.airbnb.com/"><img src="https://images.opencollective.com/airbnb/d327d66/logo.png" alt="Airbnb" height="128"></a></p><h3>Gold Sponsors</h3>
+<p><a href="#"><img src="https://images.opencollective.com/guest-bf377e88/avatar.png" alt="Eli Schleifer" height="96"></a> <a href="https://opensource.siemens.com"><img src="https://avatars.githubusercontent.com/u/624020?v=4" alt="Siemens" height="96"></a></p><h3>Silver Sponsors</h3>
+<p><a href="https://www.jetbrains.com/"><img src="https://images.opencollective.com/jetbrains/fe76f99/logo.png" alt="JetBrains" height="64"></a> <a href="https://liftoff.io/"><img src="https://images.opencollective.com/liftoff/5c4fa84/logo.png" alt="Liftoff" height="64"></a> <a href="https://americanexpress.io"><img src="https://avatars.githubusercontent.com/u/3853301?v=4" alt="American Express" height="64"></a> <a href="https://www.workleap.com"><img src="https://avatars.githubusercontent.com/u/53535748?u=d1e55d7661d724bf2281c1bfd33cb8f99fe2465f&v=4" alt="Workleap" height="64"></a></p><h3>Bronze Sponsors</h3>
+<p><a href="https://www.notion.so"><img src="https://images.opencollective.com/notion/bf3b117/logo.png" alt="notion" height="32"></a> <a href="https://www.crosswordsolver.org/anagram-solver/"><img src="https://images.opencollective.com/anagram-solver/2666271/logo.png" alt="Anagram Solver" height="32"></a> <a href="https://icons8.com/"><img src="https://images.opencollective.com/icons8/7fa1641/logo.png" alt="Icons8" height="32"></a> <a href="https://discord.com"><img src="https://images.opencollective.com/discordapp/f9645d9/logo.png" alt="Discord" height="32"></a> <a href="https://www.ignitionapp.com"><img src="https://avatars.githubusercontent.com/u/5753491?v=4" alt="Ignition" height="32"></a> <a href="https://nx.dev"><img src="https://avatars.githubusercontent.com/u/23692104?v=4" alt="Nx" height="32"></a> <a href="https://herocoders.com"><img src="https://avatars.githubusercontent.com/u/37549774?v=4" alt="HeroCoders" height="32"></a> <a href="https://usenextbase.com"><img src="https://avatars.githubusercontent.com/u/145838380?v=4" alt="Nextbase Starter Kit" height="32"></a></p>
+<!--sponsorsend-->
+
+<!--techsponsorsstart-->
+<h2>Technology Sponsors</h2>
+<p><a href="https://netlify.com"><img src="https://raw.githubusercontent.com/eslint/eslint.org/main/src/assets/images/techsponsors/netlify-icon.svg" alt="Netlify" height="32"></a> <a href="https://algolia.com"><img src="https://raw.githubusercontent.com/eslint/eslint.org/main/src/assets/images/techsponsors/algolia-icon.svg" alt="Algolia" height="32"></a> <a href="https://1password.com"><img src="https://raw.githubusercontent.com/eslint/eslint.org/main/src/assets/images/techsponsors/1password-icon.svg" alt="1Password" height="32"></a></p>
+<!--techsponsorsend-->
diff --git a/packages/eslint-visitor-keys/lib/index.js b/packages/eslint-visitor-keys/lib/index.js
new file mode 100644
index 00000000..1fc89b43
--- /dev/null
+++ b/packages/eslint-visitor-keys/lib/index.js
@@ -0,0 +1,67 @@
+/**
+ * @author Toru Nagashima <https://github.com/mysticatea>
+ * See LICENSE file in root directory for full license.
+ */
+import KEYS from "./visitor-keys.js";
+
+/**
+ * @typedef {import('./visitor-keys.js').VisitorKeys} VisitorKeys
+ */
+
+// List to ignore keys.
+const KEY_BLACKLIST = new Set([
+    "parent",
+    "leadingComments",
+    "trailingComments"
+]);
+
+/**
+ * Check whether a given key should be used or not.
+ * @param {string} key The key to check.
+ * @returns {boolean} `true` if the key should be used.
+ */
+function filterKey(key) {
+    return !KEY_BLACKLIST.has(key) && key[0] !== "_";
+}
+
+
+/* eslint-disable jsdoc/valid-types -- doesn't allow `readonly`.
+   TODO: remove eslint-disable when https://github.com/jsdoc-type-pratt-parser/jsdoc-type-pratt-parser/issues/164 is fixed
+*/
+/**
+ * Get visitor keys of a given node.
+ * @param {Object} node The AST node to get keys.
+ * @returns {readonly string[]} Visitor keys of the node.
+ */
+export function getKeys(node) {
+    return Object.keys(node).filter(filterKey);
+}
+/* eslint-enable jsdoc/valid-types -- doesn't allow `readonly` */
+
+/**
+ * Make the union set with `KEYS` and given keys.
+ * @param {VisitorKeys} additionalKeys The additional keys.
+ * @returns {VisitorKeys} The union set.
+ */
+export function unionWith(additionalKeys) {
+    const retv = /** @type {{ [type: string]: ReadonlyArray<string> }} */
+        (Object.assign({}, KEYS));
+
+    for (const type of Object.keys(additionalKeys)) {
+        if (Object.hasOwn(retv, type)) {
+            const keys = new Set(additionalKeys[type]);
+
+            for (const key of retv[type]) {
+                keys.add(key);
+            }
+
+            retv[type] = Object.freeze(Array.from(keys));
+        } else {
+            retv[type] = Object.freeze(Array.from(additionalKeys[type]));
+        }
+    }
+
+    return Object.freeze(retv);
+}
+
+export { KEYS };
diff --git a/packages/eslint-visitor-keys/lib/visitor-keys.js b/packages/eslint-visitor-keys/lib/visitor-keys.js
new file mode 100644
index 00000000..f54a3474
--- /dev/null
+++ b/packages/eslint-visitor-keys/lib/visitor-keys.js
@@ -0,0 +1,319 @@
+/* eslint-disable jsdoc/valid-types -- doesn't allow `readonly`.
+   TODO: remove eslint-disable when https://github.com/jsdoc-type-pratt-parser/jsdoc-type-pratt-parser/issues/164 is fixed
+*/
+/**
+ * @typedef {{ readonly [type: string]: ReadonlyArray<string> }} VisitorKeys
+ */
+/* eslint-enable jsdoc/valid-types -- doesn't allow `readonly string[]`. TODO: check why */
+
+/**
+ * @type {VisitorKeys}
+ */
+const KEYS = {
+    ArrayExpression: [
+        "elements"
+    ],
+    ArrayPattern: [
+        "elements"
+    ],
+    ArrowFunctionExpression: [
+        "params",
+        "body"
+    ],
+    AssignmentExpression: [
+        "left",
+        "right"
+    ],
+    AssignmentPattern: [
+        "left",
+        "right"
+    ],
+    AwaitExpression: [
+        "argument"
+    ],
+    BinaryExpression: [
+        "left",
+        "right"
+    ],
+    BlockStatement: [
+        "body"
+    ],
+    BreakStatement: [
+        "label"
+    ],
+    CallExpression: [
+        "callee",
+        "arguments"
+    ],
+    CatchClause: [
+        "param",
+        "body"
+    ],
+    ChainExpression: [
+        "expression"
+    ],
+    ClassBody: [
+        "body"
+    ],
+    ClassDeclaration: [
+        "id",
+        "superClass",
+        "body"
+    ],
+    ClassExpression: [
+        "id",
+        "superClass",
+        "body"
+    ],
+    ConditionalExpression: [
+        "test",
+        "consequent",
+        "alternate"
+    ],
+    ContinueStatement: [
+        "label"
+    ],
+    DebuggerStatement: [],
+    DoWhileStatement: [
+        "body",
+        "test"
+    ],
+    EmptyStatement: [],
+    ExperimentalRestProperty: [
+        "argument"
+    ],
+    ExperimentalSpreadProperty: [
+        "argument"
+    ],
+    ExportAllDeclaration: [
+        "exported",
+        "source"
+    ],
+    ExportDefaultDeclaration: [
+        "declaration"
+    ],
+    ExportNamedDeclaration: [
+        "declaration",
+        "specifiers",
+        "source"
+    ],
+    ExportSpecifier: [
+        "exported",
+        "local"
+    ],
+    ExpressionStatement: [
+        "expression"
+    ],
+    ForInStatement: [
+        "left",
+        "right",
+        "body"
+    ],
+    ForOfStatement: [
+        "left",
+        "right",
+        "body"
+    ],
+    ForStatement: [
+        "init",
+        "test",
+        "update",
+        "body"
+    ],
+    FunctionDeclaration: [
+        "id",
+        "params",
+        "body"
+    ],
+    FunctionExpression: [
+        "id",
+        "params",
+        "body"
+    ],
+    Identifier: [],
+    IfStatement: [
+        "test",
+        "consequent",
+        "alternate"
+    ],
+    ImportDeclaration: [
+        "specifiers",
+        "source"
+    ],
+    ImportDefaultSpecifier: [
+        "local"
+    ],
+    ImportExpression: [
+        "source"
+    ],
+    ImportNamespaceSpecifier: [
+        "local"
+    ],
+    ImportSpecifier: [
+        "imported",
+        "local"
+    ],
+    JSXAttribute: [
+        "name",
+        "value"
+    ],
+    JSXClosingElement: [
+        "name"
+    ],
+    JSXClosingFragment: [],
+    JSXElement: [
+        "openingElement",
+        "children",
+        "closingElement"
+    ],
+    JSXEmptyExpression: [],
+    JSXExpressionContainer: [
+        "expression"
+    ],
+    JSXFragment: [
+        "openingFragment",
+        "children",
+        "closingFragment"
+    ],
+    JSXIdentifier: [],
+    JSXMemberExpression: [
+        "object",
+        "property"
+    ],
+    JSXNamespacedName: [
+        "namespace",
+        "name"
+    ],
+    JSXOpeningElement: [
+        "name",
+        "attributes"
+    ],
+    JSXOpeningFragment: [],
+    JSXSpreadAttribute: [
+        "argument"
+    ],
+    JSXSpreadChild: [
+        "expression"
+    ],
+    JSXText: [],
+    LabeledStatement: [
+        "label",
+        "body"
+    ],
+    Literal: [],
+    LogicalExpression: [
+        "left",
+        "right"
+    ],
+    MemberExpression: [
+        "object",
+        "property"
+    ],
+    MetaProperty: [
+        "meta",
+        "property"
+    ],
+    MethodDefinition: [
+        "key",
+        "value"
+    ],
+    NewExpression: [
+        "callee",
+        "arguments"
+    ],
+    ObjectExpression: [
+        "properties"
+    ],
+    ObjectPattern: [
+        "properties"
+    ],
+    PrivateIdentifier: [],
+    Program: [
+        "body"
+    ],
+    Property: [
+        "key",
+        "value"
+    ],
+    PropertyDefinition: [
+        "key",
+        "value"
+    ],
+    RestElement: [
+        "argument"
+    ],
+    ReturnStatement: [
+        "argument"
+    ],
+    SequenceExpression: [
+        "expressions"
+    ],
+    SpreadElement: [
+        "argument"
+    ],
+    StaticBlock: [
+        "body"
+    ],
+    Super: [],
+    SwitchCase: [
+        "test",
+        "consequent"
+    ],
+    SwitchStatement: [
+        "discriminant",
+        "cases"
+    ],
+    TaggedTemplateExpression: [
+        "tag",
+        "quasi"
+    ],
+    TemplateElement: [],
+    TemplateLiteral: [
+        "quasis",
+        "expressions"
+    ],
+    ThisExpression: [],
+    ThrowStatement: [
+        "argument"
+    ],
+    TryStatement: [
+        "block",
+        "handler",
+        "finalizer"
+    ],
+    UnaryExpression: [
+        "argument"
+    ],
+    UpdateExpression: [
+        "argument"
+    ],
+    VariableDeclaration: [
+        "declarations"
+    ],
+    VariableDeclarator: [
+        "id",
+        "init"
+    ],
+    WhileStatement: [
+        "test",
+        "body"
+    ],
+    WithStatement: [
+        "object",
+        "body"
+    ],
+    YieldExpression: [
+        "argument"
+    ]
+};
+
+// Types.
+const NODE_TYPES = Object.keys(KEYS);
+
+// Freeze the keys.
+for (const type of NODE_TYPES) {
+    Object.freeze(KEYS[type]);
+}
+Object.freeze(KEYS);
+
+export default KEYS;
diff --git a/packages/eslint-visitor-keys/package.json b/packages/eslint-visitor-keys/package.json
new file mode 100644
index 00000000..316c29e4
--- /dev/null
+++ b/packages/eslint-visitor-keys/package.json
@@ -0,0 +1,69 @@
+{
+  "name": "eslint-visitor-keys",
+  "version": "4.0.0",
+  "description": "Constants and utilities about visitor keys to traverse AST.",
+  "type": "module",
+  "main": "dist/eslint-visitor-keys.cjs",
+  "types": "./dist/index.d.ts",
+  "exports": {
+    ".": [
+      {
+        "import": "./lib/index.js",
+        "require": "./dist/eslint-visitor-keys.cjs"
+      },
+      "./dist/eslint-visitor-keys.cjs"
+    ],
+    "./package.json": "./package.json"
+  },
+  "files": [
+    "dist/index.d.ts",
+    "dist/visitor-keys.d.ts",
+    "dist/eslint-visitor-keys.cjs",
+    "dist/eslint-visitor-keys.d.cts",
+    "lib"
+  ],
+  "engines": {
+    "node": "^18.18.0 || ^20.9.0 || >=21.1.0"
+  },
+  "devDependencies": {
+    "@types/estree": "^0.0.51",
+    "@types/estree-jsx": "^0.0.1",
+    "@typescript-eslint/parser": "^5.14.0",
+    "c8": "^7.11.0",
+    "chai": "^4.3.6",
+    "eslint-release": "^3.2.0",
+    "esquery": "^1.4.0",
+    "json-diff": "^0.7.3",
+    "mocha": "^9.2.1",
+    "opener": "^1.5.2",
+    "rollup": "^2.70.0",
+    "rollup-plugin-dts": "^4.2.3",
+    "tsd": "^0.19.1",
+    "typescript": "^4.9.5"
+  },
+  "scripts": {
+    "build": "npm run build:cjs && npm run build:types",
+    "build:cjs": "rollup -c",
+    "build:debug": "npm run build:cjs -- -m && npm run build:types",
+    "build:keys": "node tools/build-keys-from-ts",
+    "build:types": "tsc",
+    "prepare": "npm run build",
+    "release:generate:latest": "eslint-generate-release",
+    "release:generate:alpha": "eslint-generate-prerelease alpha",
+    "release:generate:beta": "eslint-generate-prerelease beta",
+    "release:generate:rc": "eslint-generate-prerelease rc",
+    "release:publish": "eslint-publish-release",
+    "test": "mocha tests/lib/**/*.cjs && c8 mocha tests/lib/**/*.js && npm run test:types",
+    "test:open-coverage": "c8 report --reporter lcov && opener coverage/lcov-report/index.html",
+    "test:types": "tsd"
+  },
+  "repository": "eslint/js",
+  "funding": "https://opencollective.com/eslint",
+  "keywords": [],
+  "author": "Toru Nagashima (https://github.com/mysticatea)",
+  "license": "Apache-2.0",
+  "bugs": {
+    "url": "https://github.com/eslint/js/issues"
+  },
+  "homepage": "https://github.com/eslint/js/blob/main/packages/eslint-visitor-keys/README.md"
+}
diff --git a/packages/eslint-visitor-keys/rollup.config.js b/packages/eslint-visitor-keys/rollup.config.js
new file mode 100644
index 00000000..9f627c9d
--- /dev/null
+++ b/packages/eslint-visitor-keys/rollup.config.js
@@ -0,0 +1,21 @@
+import dts from "rollup-plugin-dts";
+
+export default [
+    {
+        input: "./lib/index.js",
+        treeshake: false,
+        output: {
+            format: "cjs",
+            file: "dist/eslint-visitor-keys.cjs"
+        }
+    },
+    {
+        plugins: [dts()],
+        input: "./lib/index.js",
+        treeshake: false,
+        output: {
+            format: "cjs",
+            file: "dist/eslint-visitor-keys.d.cts"
+        }
+    }
+];
diff --git a/packages/eslint-visitor-keys/test-d/index.test-d.ts b/packages/eslint-visitor-keys/test-d/index.test-d.ts
new file mode 100644
index 00000000..8ff69368
--- /dev/null
+++ b/packages/eslint-visitor-keys/test-d/index.test-d.ts
@@ -0,0 +1,54 @@
+import { expectType, expectAssignable, expectError } from 'tsd';
+
+import { KEYS, getKeys, unionWith, VisitorKeys } from "../";
+
+const assignmentExpression = {
+    type: "AssignmentExpression",
+    operator: "=",
+    left: {
+        type: "Identifier",
+        name: "a",
+        range: [
+            0,
+            1
+        ]
+    },
+    right: {
+        type: "Literal",
+        value: 5,
+        raw: "5",
+        range: [
+            4,
+            5
+        ]
+    },
+    range: [
+        0,
+        5
+    ]
+};
+
+expectType<{readonly [type: string]: readonly string[]}>(KEYS);
+
+expectType<readonly string[]>(getKeys(assignmentExpression));
+
+expectType<{readonly [type: string]: readonly string[]}>(unionWith({
+    TestInterface1: ["left", "right"],
+    TestInterface2: ["expression"]
+}));
+
+const readonlyKeys: {
+    readonly [type: string]: readonly string[]
+} = {
+    TestInterface1: ["left", "right"]
+};
+
+expectAssignable<VisitorKeys>(readonlyKeys);
+
+// https://github.com/SamVerschueren/tsd/issues/143
+// expectError(() => {
+//     const erring: VisitorKeys = {
+//         TestInterface1: ["left", "right"]
+//     };
+//     erring.TestInterface1 = ["badAttemptOverwrite"];
+// });
diff --git a/packages/eslint-visitor-keys/tests/lib/commonjs.cjs b/packages/eslint-visitor-keys/tests/lib/commonjs.cjs
new file mode 100644
index 00000000..0e1d0d0b
--- /dev/null
+++ b/packages/eslint-visitor-keys/tests/lib/commonjs.cjs
@@ -0,0 +1,55 @@
+/**
+ * @fileoverview Tests for checking that the commonjs entry points are still accessible
+ * @author Mike Reinstein
+ */
+
+"use strict";
+
+//------------------------------------------------------------------------------
+// Requirements
+//------------------------------------------------------------------------------
+
+const assert = require("node:assert");
+const eslintVisitorKeys = require("../../dist/eslint-visitor-keys.cjs");
+
+
+//------------------------------------------------------------------------------
+// Tests
+//------------------------------------------------------------------------------
+
+describe("commonjs", () => {
+    it("is an object", () => {
+        assert.strictEqual(typeof eslintVisitorKeys, "object");
+    });
+
+    it("has exported keys object", () => {
+        assert.strictEqual(typeof eslintVisitorKeys.KEYS, "object");
+    });
+
+    it("has key array with AST type", () => {
+        assert.ok(Array.isArray(eslintVisitorKeys.KEYS.ArrayExpression));
+    });
+
+    it("has getKeys function", () => {
+        assert.strictEqual(typeof eslintVisitorKeys.getKeys, "function");
+    });
+
+    it("should have getKeys which returns keys", () => {
+        assert.deepStrictEqual(eslintVisitorKeys.getKeys({ a: 1, b: 2 }), ["a", "b"]);
+    });
+
+    it("has unionWith function", () => {
+        assert.strictEqual(typeof eslintVisitorKeys.unionWith, "function");
+    });
+
+    it("should have unionWith which includes all additional keys", () => {
+        const additionalKeys = { Program: ["body", "a"], AssignmentExpression: ["b"], additional: ["c"], MethodDefinition: ["a", "key", "b"] };
+        const unionKeys = eslintVisitorKeys.unionWith(additionalKeys);
+
+        for (const type of Object.keys(additionalKeys)) {
+            for (const key of additionalKeys[type]) {
+                assert(unionKeys[type].includes(key), `'${key}' should be included in '${type}'.`);
+            }
+        }
+    });
+});
diff --git a/packages/eslint-visitor-keys/tests/lib/fixtures/bad-extends-type-reference.d.ts b/packages/eslint-visitor-keys/tests/lib/fixtures/bad-extends-type-reference.d.ts
new file mode 100644
index 00000000..1457d679
--- /dev/null
+++ b/packages/eslint-visitor-keys/tests/lib/fixtures/bad-extends-type-reference.d.ts
@@ -0,0 +1,3 @@
+export interface Something extends BadSomething {
+  type: "Something";
+}
diff --git a/packages/eslint-visitor-keys/tests/lib/fixtures/bad-type-parameters.d.ts b/packages/eslint-visitor-keys/tests/lib/fixtures/bad-type-parameters.d.ts
new file mode 100644
index 00000000..0095c9c2
--- /dev/null
+++ b/packages/eslint-visitor-keys/tests/lib/fixtures/bad-type-parameters.d.ts
@@ -0,0 +1,5 @@
+export interface Statement {}
+
+export interface StaticBlock extends BadTypeParam<Statement, 'type'> {
+    type: "StaticBlock";
+}
diff --git a/packages/eslint-visitor-keys/tests/lib/fixtures/bad-type-reference.d.ts b/packages/eslint-visitor-keys/tests/lib/fixtures/bad-type-reference.d.ts
new file mode 100644
index 00000000..9c226f18
--- /dev/null
+++ b/packages/eslint-visitor-keys/tests/lib/fixtures/bad-type-reference.d.ts
@@ -0,0 +1,3 @@
+export interface StaticBlock extends Omit<SomeUnknownStatement, 'type'> {
+    type: "StaticBlock";
+}
diff --git a/packages/eslint-visitor-keys/tests/lib/fixtures/bad-type-value.d.ts b/packages/eslint-visitor-keys/tests/lib/fixtures/bad-type-value.d.ts
new file mode 100644
index 00000000..973aa2bb
--- /dev/null
+++ b/packages/eslint-visitor-keys/tests/lib/fixtures/bad-type-value.d.ts
@@ -0,0 +1,8 @@
+interface BadExpression {
+  type: undefined;
+}
+
+export interface NewFangledExpression {
+  type: "NewFangledExpression";
+  right: BadExpression;
+}
diff --git a/packages/eslint-visitor-keys/tests/lib/fixtures/bad-type.d.ts b/packages/eslint-visitor-keys/tests/lib/fixtures/bad-type.d.ts
new file mode 100644
index 00000000..ce4b9830
--- /dev/null
+++ b/packages/eslint-visitor-keys/tests/lib/fixtures/bad-type.d.ts
@@ -0,0 +1,4 @@
+export interface SomeExpression {
+  type: "SomeExpression";
+  someProperty: any;
+}
diff --git a/packages/eslint-visitor-keys/tests/lib/fixtures/new-keys-bad.d.ts b/packages/eslint-visitor-keys/tests/lib/fixtures/new-keys-bad.d.ts
new file mode 100644
index 00000000..99389eac
--- /dev/null
+++ b/packages/eslint-visitor-keys/tests/lib/fixtures/new-keys-bad.d.ts
@@ -0,0 +1,4 @@
+export interface NewFangledExpression {
+  type: "NewFangledExpression";
+  right: BadExpression;
+}
diff --git a/packages/eslint-visitor-keys/tests/lib/fixtures/new-keys-on-old-order-switched.d.ts b/packages/eslint-visitor-keys/tests/lib/fixtures/new-keys-on-old-order-switched.d.ts
new file mode 100644
index 00000000..dc0141da
--- /dev/null
+++ b/packages/eslint-visitor-keys/tests/lib/fixtures/new-keys-on-old-order-switched.d.ts
@@ -0,0 +1,20 @@
+export type AssignmentOperator = "=";
+interface Pattern {
+    type: "Pattern"
+};
+interface MemberExpression {
+    type: "MemberExpression"
+};
+interface Expression {
+    type: "Expression"
+};
+
+export interface AssignmentExpression {
+  type: "AssignmentExpression";
+  operator: AssignmentOperator;
+  down: Expression;
+  up: Expression;
+  left: Pattern | MemberExpression;
+  right: Expression;
+  nontraversable: RegExp;
+}
diff --git a/packages/eslint-visitor-keys/tests/lib/fixtures/new-keys-on-old-other-order.d.ts b/packages/eslint-visitor-keys/tests/lib/fixtures/new-keys-on-old-other-order.d.ts
new file mode 100644
index 00000000..3f9d5d34
--- /dev/null
+++ b/packages/eslint-visitor-keys/tests/lib/fixtures/new-keys-on-old-other-order.d.ts
@@ -0,0 +1,20 @@
+export type AssignmentOperator = "=";
+interface Pattern {
+    type: "Pattern"
+};
+interface MemberExpression {
+    type: "MemberExpression"
+};
+interface Expression {
+    type: "Expression"
+};
+
+export interface AssignmentExpression {
+  type: "AssignmentExpression";
+  operator: AssignmentOperator;
+  up: Expression;
+  left: Pattern | MemberExpression;
+  down: Expression;
+  right: Expression;
+  nontraversable: RegExp;
+}
diff --git a/packages/eslint-visitor-keys/tests/lib/fixtures/new-keys-on-old.d.ts b/packages/eslint-visitor-keys/tests/lib/fixtures/new-keys-on-old.d.ts
new file mode 100644
index 00000000..1ac742c0
--- /dev/null
+++ b/packages/eslint-visitor-keys/tests/lib/fixtures/new-keys-on-old.d.ts
@@ -0,0 +1,35 @@
+export type AssignmentOperator = "=";
+
+interface IgnoreBase {
+    type: "Line";
+}
+
+type AnotherIgnore = IgnoreBase;
+
+interface BasePattern {
+    type: "Pattern"
+};
+interface IgnoreChild extends Omit<BasePattern, "type"> {
+};
+
+interface Pattern {
+    type: "Pattern"
+};
+interface MemberExpression {
+    type: "MemberExpression"
+};
+interface Expression {
+    type: "Expression"
+};
+
+export interface AssignmentExpression {
+  type: "AssignmentExpression";
+  ignore: IgnoreChild;
+  anotherIgnore: AnotherIgnore;
+  operator: AssignmentOperator;
+  up: Expression;
+  down: Expression;
+  left: Pattern | MemberExpression;
+  right: Expression;
+  nontraversable: RegExp;
+}
diff --git a/packages/eslint-visitor-keys/tests/lib/fixtures/new-keys.d.ts b/packages/eslint-visitor-keys/tests/lib/fixtures/new-keys.d.ts
new file mode 100644
index 00000000..6ff0aa89
--- /dev/null
+++ b/packages/eslint-visitor-keys/tests/lib/fixtures/new-keys.d.ts
@@ -0,0 +1,19 @@
+export type AssignmentOperator = "=";
+interface Pattern {
+    type: "Pattern"
+};
+interface MemberExpression {
+    type: "MemberExpression"
+};
+interface Expression {
+    type: "Expression"
+};
+
+export interface NewFangledExpression {
+  type: "NewFangledExpression";
+  operator: AssignmentOperator;
+  up: Expression;
+  down: Expression;
+  left: Pattern | MemberExpression;
+  right: Expression;
+}
diff --git a/packages/eslint-visitor-keys/tests/lib/fixtures/union-omit.d.ts b/packages/eslint-visitor-keys/tests/lib/fixtures/union-omit.d.ts
new file mode 100644
index 00000000..d6088df3
--- /dev/null
+++ b/packages/eslint-visitor-keys/tests/lib/fixtures/union-omit.d.ts
@@ -0,0 +1,11 @@
+export interface IgnoredStatement {
+    type: "IgnoredStatement"
+}
+export interface AnotherStatement {
+    type: "AnotherStatement";
+    anotherToIgnore: IgnoredStatement;
+}
+
+export interface StaticBlock extends Omit<AnotherStatement, 'type' | 'anotherToIgnore'> {
+    type: "StaticBlock";
+}
diff --git a/packages/eslint-visitor-keys/tests/lib/get-keys-from-ts.js b/packages/eslint-visitor-keys/tests/lib/get-keys-from-ts.js
new file mode 100644
index 00000000..9b32795d
--- /dev/null
+++ b/packages/eslint-visitor-keys/tests/lib/get-keys-from-ts.js
@@ -0,0 +1,201 @@
+/**
+ * @fileoverview Tests for checking that our build tool can retrieve keys out of TypeScript AST.
+ * @author Brett Zamir
+ */
+
+import { diffString } from "json-diff";
+import { expect } from "chai";
+import { alphabetizeKeyInterfaces, getKeysFromTsFile } from "../../tools/get-keys-from-ts.js";
+import { KEYS } from "../../lib/index.js";
+import backwardCompatibleKeys from "../../tools/backward-compatible-keys.js";
+
+describe("getKeysFromTsFile", () => {
+    it("gets keys", async () => {
+        const { keys, tsInterfaceDeclarations } = await getKeysFromTsFile(
+            "../../node_modules/@types/estree/index.d.ts"
+        );
+        const { keys: jsxKeys } = await getKeysFromTsFile(
+            "../../node_modules/@types/estree-jsx/index.d.ts",
+            {
+                supplementaryDeclarations: tsInterfaceDeclarations
+            }
+        );
+
+        const actual = alphabetizeKeyInterfaces({ ...keys, ...jsxKeys, ...backwardCompatibleKeys });
+
+        const expected = KEYS;
+
+        // eslint-disable-next-line no-console -- Mocha's may drop diffs so show with json-diff
+        console.log("JSON Diffs:", diffString(actual, expected) || "(none)");
+
+        expect(actual).to.deep.equal(expected);
+    });
+
+    it("gets keys minus explicitly omitted ones", async () => {
+        const { keys: actual } = await getKeysFromTsFile(
+            "./tests/lib/fixtures/union-omit.d.ts"
+        );
+
+        const expected = {
+            AnotherStatement: [
+                "anotherToIgnore"
+            ],
+            IgnoredStatement: [],
+            StaticBlock: []
+        };
+
+        expect(actual).to.deep.equal(expected);
+    });
+
+    it("sorts keys alphabetically if new", async () => {
+        const { keys: actual } = await getKeysFromTsFile(
+            "./tests/lib/fixtures/new-keys.d.ts"
+        );
+
+        const expected = {
+            NewFangledExpression: [
+                "down",
+                "left",
+                "right",
+                "up"
+            ]
+        };
+
+        expect(actual).to.deep.equal(expected);
+    });
+
+    it("sorts extra keys at end alphabetically", async () => {
+        const { keys: actual } = await getKeysFromTsFile(
+            "./tests/lib/fixtures/new-keys-on-old.d.ts"
+        );
+
+        const expected = {
+            AssignmentExpression: [
+                "left",
+                "right",
+                "down",
+                "up"
+            ]
+        };
+
+        expect(actual).to.deep.equal(expected);
+    });
+
+    it("sorts extra keys at end alphabetically (other order)", async () => {
+        const { keys: actual } = await getKeysFromTsFile(
+            "./tests/lib/fixtures/new-keys-on-old-other-order.d.ts"
+        );
+
+        const expected = {
+            AssignmentExpression: [
+                "left",
+                "right",
+                "down",
+                "up"
+            ]
+        };
+
+        expect(actual).to.deep.equal(expected);
+    });
+
+    it("sorts extra keys at end alphabetically (switched order)", async () => {
+        const { keys: actual } = await getKeysFromTsFile(
+            "./tests/lib/fixtures/new-keys-on-old-order-switched.d.ts"
+        );
+
+        const expected = {
+            AssignmentExpression: [
+                "left",
+                "right",
+                "down",
+                "up"
+            ]
+        };
+
+        expect(actual).to.deep.equal(expected);
+    });
+
+    it("throws with unhandled TS type reference", async () => {
+        let error;
+
+        try {
+            await getKeysFromTsFile(
+                "./tests/lib/fixtures/bad-type-reference.d.ts"
+            );
+        } catch (err) {
+            error = err;
+        }
+
+        expect(error.message).to.contain("Unhandled TypeScript type reference");
+    });
+
+    it("throws with unhandled extends TS type reference", async () => {
+        let error;
+
+        try {
+            await getKeysFromTsFile(
+                "./tests/lib/fixtures/bad-extends-type-reference.d.ts"
+            );
+        } catch (err) {
+            error = err;
+        }
+
+        expect(error.message).to.contain("Unhandled TypeScript type reference");
+    });
+
+    it("throws with unhandled TS type", async () => {
+        let error;
+
+        try {
+            await getKeysFromTsFile(
+                "./tests/lib/fixtures/bad-type.d.ts"
+            );
+        } catch (err) {
+            error = err;
+        }
+
+        expect(error.message).to.contain("Unhandled TypeScript type;");
+    });
+
+    it("throws with unhandled TS typeParameters", async () => {
+        let error;
+
+        try {
+            await getKeysFromTsFile(
+                "./tests/lib/fixtures/bad-type-parameters.d.ts"
+            );
+        } catch (err) {
+            error = err;
+        }
+
+        expect(error.message).to.contain("Unknown type parameter");
+    });
+
+    it("throws with bad key", async () => {
+        let error;
+
+        try {
+            await getKeysFromTsFile(
+                "./tests/lib/fixtures/new-keys-bad.d.ts"
+            );
+        } catch (err) {
+            error = err;
+        }
+
+        expect(error.message).to.equal("Type unknown as to traversability: BadExpression");
+    });
+
+    it("throws with bad type value", async () => {
+        let error;
+
+        try {
+            await getKeysFromTsFile(
+                "./tests/lib/fixtures/bad-type-value.d.ts"
+            );
+        } catch (err) {
+            error = err;
+        }
+
+        expect(error.message).to.equal("Unexpected `type` value property type TSUndefinedKeyword");
+    });
+});
diff --git a/packages/eslint-visitor-keys/tests/lib/index.js b/packages/eslint-visitor-keys/tests/lib/index.js
new file mode 100644
index 00000000..15922127
--- /dev/null
+++ b/packages/eslint-visitor-keys/tests/lib/index.js
@@ -0,0 +1,66 @@
+/**
+ * @author Toru Nagashima <https://github.com/mysticatea>
+ * See LICENSE file in root directory for full license.
+ */
+import assert from "node:assert";
+import * as evk from "../../lib/index.js";
+import keys from "../../lib/visitor-keys.js";
+
+describe("eslint-visitor-keys", () => {
+    describe("KEYS", () => {
+        it("should be same as lib/visitor-keys.js", () => {
+            assert.deepStrictEqual(evk.KEYS, keys);
+        });
+    });
+
+    describe("getKeys()", () => {
+        it("should return keys", () => {
+            assert.deepStrictEqual(evk.getKeys({ a: 1, b: 2 }), ["a", "b"]);
+        });
+
+        it("should not include 'parent' in the result", () => {
+            assert.deepStrictEqual(evk.getKeys({ a: 1, b: 2, parent: 3 }), ["a", "b"]);
+        });
+
+        it("should not include 'leadingComments' in the result", () => {
+            assert.deepStrictEqual(evk.getKeys({ a: 1, b: 2, leadingComments: 3 }), ["a", "b"]);
+        });
+
+        it("should not include 'trailingComments' in the result", () => {
+            assert.deepStrictEqual(evk.getKeys({ a: 1, b: 2, trailingComments: 3 }), ["a", "b"]);
+        });
+
+        it("should not include '_foo' in the result", () => {
+            assert.deepStrictEqual(evk.getKeys({ a: 1, b: 2, _foo: 3 }), ["a", "b"]);
+        });
+    });
+
+    describe("unionWith()", () => {
+        const additionalKeys = { Program: ["body", "a"], AssignmentExpression: ["b"], additional: ["c"], MethodDefinition: ["a", "key", "b"] };
+        const unionKeys = evk.unionWith(additionalKeys);
+
+        it("should include all keys of lib/visitor-keys.js", () => {
+            for (const type of Object.keys(keys)) {
+                for (const key of keys[type]) {
+                    assert(unionKeys[type].includes(key), `'${key}' should be included in '${type}'.`);
+                }
+            }
+        });
+
+        it("should include all additional keys", () => {
+            for (const type of Object.keys(additionalKeys)) {
+                for (const key of additionalKeys[type]) {
+                    assert(unionKeys[type].includes(key), `'${key}' should be included in '${type}'.`);
+                }
+            }
+        });
+
+        it("should not have duplicate", () => {
+            assert(unionKeys.Program.filter(key => key === "body").length === 1);
+        });
+
+        it("should add additional keys, then concatenate original keys", () => {
+            assert.deepStrictEqual(unionKeys.MethodDefinition, ["a", "key", "b", "value"]);
+        });
+    });
+});
diff --git a/packages/eslint-visitor-keys/tools/backward-compatible-keys.js b/packages/eslint-visitor-keys/tools/backward-compatible-keys.js
new file mode 100644
index 00000000..ead9e70a
--- /dev/null
+++ b/packages/eslint-visitor-keys/tools/backward-compatible-keys.js
@@ -0,0 +1,10 @@
+const backwardCompatibleKeys = {
+    ExperimentalRestProperty: [
+        "argument"
+    ],
+    ExperimentalSpreadProperty: [
+        "argument"
+    ]
+};
+
+export default backwardCompatibleKeys;
diff --git a/packages/eslint-visitor-keys/tools/build-keys-from-ts.js b/packages/eslint-visitor-keys/tools/build-keys-from-ts.js
new file mode 100644
index 00000000..7d7e8a73
--- /dev/null
+++ b/packages/eslint-visitor-keys/tools/build-keys-from-ts.js
@@ -0,0 +1,55 @@
+/**
+ * @fileoverview Script to build our visitor keys based on TypeScript AST.
+ *
+ * Uses `get-keys-from-ts.js` to read the files and build the keys and then
+ * merges them in alphabetical order of Node type before writing to file.
+ *
+ * @author Brett Zamir
+ */
+
+import fs from "node:fs";
+import { alphabetizeKeyInterfaces, getKeysFromTsFile } from "./get-keys-from-ts.js";
+import backwardCompatibleKeys from "./backward-compatible-keys.js";
+
+const { promises: { writeFile } } = fs;
+
+(async () => {
+    const { keys, tsInterfaceDeclarations } = await getKeysFromTsFile("./node_modules/@types/estree/index.d.ts");
+    const { keys: jsxKeys } = await getKeysFromTsFile(
+        "./node_modules/@types/estree-jsx/index.d.ts",
+        {
+            supplementaryDeclarations: tsInterfaceDeclarations
+        }
+    );
+
+    const mergedKeys = alphabetizeKeyInterfaces({ ...keys, ...jsxKeys, ...backwardCompatibleKeys });
+
+
+    console.log("keys", mergedKeys);
+
+    writeFile(
+        "./lib/visitor-keys.js",
+        // eslint-disable-next-line indent -- Readability
+`/**
+ * @typedef {{ readonly [type: string]: ReadonlyArray<string> }} VisitorKeys
+ */
+
+/**
+ * @type {VisitorKeys}
+ */
+const KEYS = ${JSON.stringify(mergedKeys, null, 4).replace(/"(.*?)":/gu, "$1:")};
+
+// Types.
+const NODE_TYPES = Object.keys(KEYS);
+
+// Freeze the keys.
+for (const type of NODE_TYPES) {
+    Object.freeze(KEYS[type]);
+}
+Object.freeze(KEYS);
+
+export default KEYS;
+`
+    );
+
+})();
diff --git a/packages/eslint-visitor-keys/tools/get-keys-from-ts.js b/packages/eslint-visitor-keys/tools/get-keys-from-ts.js
new file mode 100644
index 00000000..1902fb39
--- /dev/null
+++ b/packages/eslint-visitor-keys/tools/get-keys-from-ts.js
@@ -0,0 +1,546 @@
+/**
+ * @fileoverview Script to build our visitor keys based on TypeScript AST.
+ *
+ * Uses `get-keys-from-ts.js` to read the files and build the keys and then
+ * merges them in alphabetical order of Node type before writing to file.
+ *
+ * @author Brett Zamir
+ */
+
+//------------------------------------------------------------------------------
+// Requirements
+//------------------------------------------------------------------------------
+
+import { promises } from "node:fs";
+import { parseForESLint } from "@typescript-eslint/parser";
+import esquery from "esquery";
+
+import { getKeys, KEYS } from "../lib/index.js";
+
+const { readFile } = promises;
+
+//------------------------------------------------------------------------------
+// Helpers
+//------------------------------------------------------------------------------
+
+const knownTypes = new Set([
+    "TSUndefinedKeyword",
+    "TSNullKeyword",
+    "TSUnknownKeyword",
+    "TSBooleanKeyword",
+    "TSNumberKeyword",
+    "TSStringKeyword",
+    "TSLiteralType", // E.g., `true`
+
+    // Apparently used for primitives, so exempting
+    "TSTypeLiteral", // E.g., `{value: {cooked, raw}}`
+
+    "TSUnionType", // I.e., `|`
+    "TSTypeReference"
+]);
+
+const notTraversableTypes = new Set([
+    "RegExp"
+]);
+
+const notTraversableTSTypes = new Set([
+    "TSUndefinedKeyword",
+    "TSNullKeyword",
+    "TSBooleanKeyword",
+    "TSNumberKeyword",
+    "TSStringKeyword",
+    "TSBigIntKeyword",
+    "TSLiteralType"
+]);
+
+const commentTypes = new Set([
+    "Line",
+    "Block"
+]);
+
+/**
+ * Get the literal names out of AST
+ * @param {Node} excludedItem Excluded node
+ * @returns {string[]} The literal names
+ */
+function findOmitTypes(excludedItem) {
+    if (excludedItem.type === "TSUnionType") {
+        return excludedItem.types.map(typeNode => findOmitTypes(typeNode));
+    }
+    return excludedItem.literal.value;
+}
+
+/**
+ * Checks whether property should be excluded
+ * @param {string} property Property to check
+ * @param {string[]} excludedProperties Properties not to allow
+ * @returns {boolean} Whether or not to be excluded
+ */
+function isPropertyExcluded(property, excludedProperties) {
+    return excludedProperties && excludedProperties.includes(property);
+}
+
+//------------------------------------------------------------------------------
+// Public APIs
+//------------------------------------------------------------------------------
+
+/**
+ * Returns alphabetized keys
+ * @param {KeysStrict} initialNodes Initial node list to sort
+ * @returns {KeysStrict} The keys
+ */
+function alphabetizeKeyInterfaces(initialNodes) {
+
+    /**
+     * Alphabetize
+     * @param {string} typeA The first type to compare
+     * @param {string} typeB The second type to compare
+     * @returns {1|-1} The sorting index
+     */
+    function alphabetize([typeA], [typeB]) {
+        return typeA < typeB ? -1 : 1;
+    }
+    const sortedNodeEntries = Object.entries(initialNodes).sort(alphabetize);
+
+    /**
+     * Get the key sorter for a given type
+     * @param {string} type The type
+     * @returns {(string, string) => -1|1} The sorter
+     */
+    function getKeySorter(type) {
+        const sequence = KEYS[type];
+
+        /**
+         * Alphabetize
+         * @param {string} typeA The first type to compare
+         * @param {string} typeB The second type to compare
+         * @returns {1|-1} The sorting index
+         */
+        return function sortKeys(typeA, typeB) {
+            if (!sequence) {
+                return typeA < typeB ? -1 : 1;
+            }
+
+            const idxA = sequence.indexOf(typeA);
+            const idxB = sequence.indexOf(typeB);
+
+            if (idxA === -1 && idxB === -1) {
+                return typeA < typeB ? -1 : 1;
+            }
+            if (idxA === -1) {
+                return 1;
+            }
+            if (idxB === -1) {
+                return -1;
+            }
+
+            return idxA < idxB ? -1 : 1;
+        };
+    }
+
+    for (const [type, keys] of sortedNodeEntries) {
+        keys.sort(getKeySorter(type));
+    }
+
+    return Object.fromEntries(sortedNodeEntries);
+}
+
+/**
+ * Traverse interface `extends`
+ * @param {Node} declNode The TS declaration node
+ * @param {Function} handler The callback
+ * @returns {any[]} Return value of handler
+ * @throws {Error} If it finds an unknown type parameter.
+ */
+function traverseExtends(declNode, handler) {
+    const ret = [];
+
+    for (const extension of declNode.extends || []) {
+        const { typeParameters, expression } = extension;
+        const innerInterfaceName = expression.name;
+
+        let res;
+
+        if (typeParameters) {
+            if (innerInterfaceName !== "Omit") {
+                throw new Error("Unknown type parameter");
+            }
+
+            const [param, ...excludedAST] = typeParameters.params;
+            const paramInterfaceName = param.typeName.name;
+            const excluded = excludedAST.flatMap(findOmitTypes);
+
+            res = handler({ iName: paramInterfaceName, excluded });
+        } else {
+            res = handler({ iName: innerInterfaceName });
+        }
+
+        ret.push(res);
+    }
+
+    return ret;
+}
+
+/**
+ * Traverse the properties of a declaration node.
+ * @param {Node} tsDeclarationNode The declaration node
+ * @param {(string) => void} handler Passed the property
+ * @returns {any[]} The return values of the callback
+ */
+function traverseProperties(tsDeclarationNode, handler) {
+    const tsPropertySignatures = tsDeclarationNode.body.body;
+
+    const ret = [];
+
+    for (const tsPropertySignature of tsPropertySignatures) {
+        const property = tsPropertySignature.key.name;
+
+        const tsAnnotation = tsPropertySignature.typeAnnotation.typeAnnotation;
+
+        const res = handler({ property, tsAnnotation });
+
+        ret.push(res);
+    }
+
+    return ret;
+}
+
+/**
+ * Builds visitor keys based on TypeScript declaration.
+ * @param {string} code TypeScript declaration file as code to parse.
+ * @param {{supplementaryDeclarations: Node[]}} [options] The options
+ * @returns {VisitorKeysExport} The built visitor keys
+ * @throws {Error} If it finds an unknown type.
+ */
+function getKeysFromTs(code, {
+
+    // Todo: Ideally we'd just get these from the import
+    supplementaryDeclarations = {
+        allTsInterfaceDeclarations: [],
+        exportedTsInterfaceDeclarations: [],
+        tsTypeDeclarations: []
+    }
+} = {}) {
+    const unrecognizedTSTypeReferences = new Set();
+    const unrecognizedTSTypes = new Set();
+
+    const parsedTSDeclaration = parseForESLint(code);
+
+    const allTsInterfaceDeclarations = [...esquery.query(
+        parsedTSDeclaration.ast,
+        "TSInterfaceDeclaration",
+        {
+
+            // TypeScript keys here to find our *.d.ts nodes (not for the ESTree
+            //   ones we want)
+            visitorKeys: parsedTSDeclaration.visitorKeys
+        }
+    ), ...supplementaryDeclarations.allTsInterfaceDeclarations];
+
+    const exportedTsInterfaceDeclarations = [...esquery.query(
+        parsedTSDeclaration.ast,
+        "ExportNamedDeclaration > TSInterfaceDeclaration",
+        {
+
+            // TypeScript keys here to find our *.d.ts nodes (not for the ESTree
+            //   ones we want)
+            visitorKeys: parsedTSDeclaration.visitorKeys
+        }
+    ), ...supplementaryDeclarations.exportedTsInterfaceDeclarations];
+
+    const tsTypeDeclarations = [...esquery.query(
+        parsedTSDeclaration.ast,
+        "TSTypeAliasDeclaration",
+        {
+
+            // TypeScript keys here to find our *.d.ts nodes (not for the ESTree
+            //   ones we want)
+            visitorKeys: parsedTSDeclaration.visitorKeys
+        }
+    ), ...supplementaryDeclarations.tsTypeDeclarations];
+
+    const initialNodes = {};
+
+    /**
+     * Finds a TypeScript interface declaration.
+     * @param {string} interfaceName The type name.
+     * @returns {Node} The interface declaration node
+     */
+    function findTsInterfaceDeclaration(interfaceName) {
+        return allTsInterfaceDeclarations.find(
+            innerTsDeclaration => innerTsDeclaration.id.name === interfaceName
+        );
+    }
+
+    /**
+     * Finds a TypeScript type declaration.
+     * @param {string} typeName A type name
+     * @returns {Node} The type declaration node
+     */
+    function findTsTypeDeclaration(typeName) {
+        return tsTypeDeclarations.find(typeDecl => typeDecl.id.name === typeName);
+    }
+
+    /**
+     * Whether has a valid (non-comment) type
+     * @param {Object} cfg Config object
+     * @param {string} cfg.property The property name
+     * @param {Node} cfg.tsAnnotation The annotation node
+     * @returns {boolean} Whether has a traverseable type
+     * @throws {Error} If it finds an unknown type.
+     */
+    function hasValidType({ property, tsAnnotation }) {
+        const tsPropertyType = tsAnnotation.type;
+
+        if (property !== "type") {
+            return false;
+        }
+
+        switch (tsPropertyType) {
+            case "TSLiteralType":
+                return typeof tsAnnotation.literal.value === "string" &&
+                    !commentTypes.has(tsAnnotation.literal.value);
+            case "TSStringKeyword":
+
+                // Ok, but not sufficient
+                return false;
+            case "TSUnionType":
+                return tsAnnotation.types.some(annType => hasValidType({
+                    property: "type",
+                    tsAnnotation: annType
+                }));
+            default:
+                throw new Error(`Unexpected \`type\` value property type ${tsPropertyType}`);
+        }
+    }
+
+    /**
+     * Whether the interface has a valid type ancestor
+     * @param {string} interfaceName The interface to check
+     * @returns {void}
+     * @throws {Error} If it finds an unknown type.
+     */
+    function hasValidTypeAncestor(interfaceName) {
+        let decl = findTsInterfaceDeclaration(interfaceName);
+
+        if (decl) {
+            if (traverseProperties(decl, hasValidType).some(hasValid => hasValid)) {
+                return true;
+            }
+        }
+
+        if (!decl) {
+            decl = findTsTypeDeclaration(interfaceName);
+            if (decl) {
+                if (!decl.typeAnnotation.types) {
+                    return notTraversableTSTypes.has(decl.typeAnnotation.type)
+                        ? false
+                        : hasValidTypeAncestor(decl.typeAnnotation.typeName.name);
+                }
+
+                return decl.typeAnnotation.types.some(type => {
+                    if (!type.typeName) {
+
+                        // Literal
+                        return false;
+                    }
+
+                    return hasValidTypeAncestor(type.typeName.name);
+                });
+            }
+        }
+
+        if (!decl) {
+            throw new Error(`Type unknown as to traversability: ${interfaceName}`);
+        }
+
+        if (traverseExtends(decl, ({ iName, excluded }) => {
+
+            // We don't want to look at this ancestor's `type` if being excluded
+            if (excluded && excluded.includes("type")) {
+                return false;
+            }
+
+            return hasValidTypeAncestor(iName);
+        }).some(hasValid => hasValid)) {
+            return true;
+        }
+
+        return false;
+    }
+
+    /**
+     * Determine whether the Node is traversable
+     * @param {Node} annotationType The annotation type Node
+     * @param {string} property The property name
+     * @returns {boolean} Whether the node is traversable
+     */
+    function checkTraversability(annotationType, property) {
+        if (
+            notTraversableTSTypes.has(annotationType.type)
+        ) {
+            return false;
+        }
+
+        if (annotationType.type === "TSTupleType") {
+            return annotationType.elementTypes.some(annType => checkTraversability(annType, property));
+        }
+
+        if (annotationType.type === "TSUnionType") {
+            return annotationType.types.some(annType => checkTraversability(annType, property));
+        }
+
+        if (annotationType.typeName.name === "Array") {
+            return annotationType.typeParameters.params.some(annType => checkTraversability(annType, property));
+        }
+
+        if (
+            notTraversableTypes.has(annotationType.typeName.name)
+        ) {
+            return false;
+        }
+
+        if (hasValidTypeAncestor(annotationType.typeName.name)) {
+            return true;
+        }
+
+        return false;
+    }
+
+    /**
+     * Adds a property to a node based on a type declaration node's contents.
+     * @param {Node} tsDeclarationNode TypeScript declaration node
+     * @param {Node} node The Node on which to build
+     * @param {string[]} excludedProperties Excluded properties
+     * @returns {void}
+     */
+    function addPropertyToNodeForDeclaration(tsDeclarationNode, node, excludedProperties) {
+
+        traverseProperties(tsDeclarationNode, ({ property, tsAnnotation }) => {
+            if (isPropertyExcluded(property, excludedProperties)) {
+                return;
+            }
+
+            const tsPropertyType = tsAnnotation.type;
+
+            if (property === "type" && tsPropertyType === "TSLiteralType") {
+
+                // console.log('tsAnnotation', tsAnnotation);
+                // node[property] = tsAnnotation.literal.value;
+                // return;
+            }
+
+            // For sanity-checking
+            if (!knownTypes.has(tsPropertyType)) {
+                unrecognizedTSTypes.add(tsPropertyType);
+                return;
+            }
+
+            switch (tsPropertyType) {
+                case "TSUnionType":
+                    if (tsAnnotation.types.some(annType => checkTraversability(annType, property))) {
+                        break;
+                    }
+                    return;
+                case "TSTypeReference": {
+                    if (checkTraversability(tsAnnotation, property)) {
+                        break;
+                    }
+
+                    return;
+                } default:
+                    return;
+            }
+
+            node[property] = null;
+        });
+
+        traverseExtends(tsDeclarationNode, ({ iName, excluded }) => {
+            const innerTsDeclarationNode = findTsInterfaceDeclaration(iName);
+
+            if (!innerTsDeclarationNode) {
+                unrecognizedTSTypeReferences.add(iName);
+                return;
+            }
+
+            addPropertyToNodeForDeclaration(innerTsDeclarationNode, node, excluded);
+        });
+    }
+
+    for (const tsDeclarationNode of exportedTsInterfaceDeclarations) {
+        const bodyType = tsDeclarationNode.body.body.find(
+            prop => prop.key.name === "type"
+        );
+
+        const typeName = bodyType && bodyType.typeAnnotation &&
+            bodyType.typeAnnotation.typeAnnotation &&
+            bodyType.typeAnnotation.typeAnnotation.literal &&
+            bodyType.typeAnnotation.typeAnnotation.literal.value;
+
+        if (!typeName) {
+            continue;
+        }
+
+        const node = {};
+
+        addPropertyToNodeForDeclaration(tsDeclarationNode, node);
+
+        initialNodes[typeName] = [...new Set(getKeys(node), ...(initialNodes[typeName] || []))];
+    }
+
+    const nodes = alphabetizeKeyInterfaces(initialNodes);
+
+    if (unrecognizedTSTypes.size) {
+        throw new Error(
+            "Unhandled TypeScript type; please update the code to " +
+            "handle the type or if not relevant, add it to " +
+            "`unrecognizedTSTypes`; see\n\n  " +
+            `${[...unrecognizedTSTypes].join(", ")}\n`
+        );
+    }
+    if (unrecognizedTSTypeReferences.size) {
+        throw new Error(
+            "Unhandled TypeScript type reference; please update the code to " +
+            "handle the type reference or if not relevant, add it to " +
+            "`unrecognizedTSTypeReferences`; see\n\n  " +
+            `${[...unrecognizedTSTypeReferences].join(", ")}\n`
+        );
+    }
+
+    return {
+        keys: nodes,
+        tsInterfaceDeclarations: {
+            allTsInterfaceDeclarations,
+            exportedTsInterfaceDeclarations,
+            tsTypeDeclarations
+        }
+    };
+}
+
+/**
+ * @typedef {{
+ *   keys: KeysStrict,
+ *   tsInterfaceDeclarations: {
+ *     allTsInterfaceDeclarations: Node[],
+ *     exportedTsInterfaceDeclarations: Node[]
+ *   }
+ * }} VisitorKeysExport
+ */
+
+/**
+ * Builds visitor keys based on TypeScript declaration.
+ * @param {string} file TypeScript declaration file to parse.
+ * @param {{supplementaryDeclarations: Object<string, Node[]>}} options The options
+ * @returns {Promise<VisitorKeysExport>} The built visitor keys
+ */
+async function getKeysFromTsFile(file, options) {
+    const code = await readFile(file);
+
+    return getKeysFromTs(code, options);
+}
+
+//------------------------------------------------------------------------------
+// Public Interface
+//------------------------------------------------------------------------------
+
+export { alphabetizeKeyInterfaces, getKeysFromTs, getKeysFromTsFile };
diff --git a/packages/eslint-visitor-keys/tsconfig.json b/packages/eslint-visitor-keys/tsconfig.json
new file mode 100644
index 00000000..57d4de12
--- /dev/null
+++ b/packages/eslint-visitor-keys/tsconfig.json
@@ -0,0 +1,19 @@
+{
+  "compilerOptions": {
+    "lib": ["es2022"],
+    "moduleResolution": "node",
+    "module": "esnext",
+    "resolveJsonModule": true,
+    "allowJs": true,
+    "checkJs": true,
+    "noEmit": false,
+    "declaration": true,
+    "declarationMap": true,
+    "emitDeclarationOnly": true,
+    "strict": true,
+    "target": "es6",
+    "outDir": "dist"
+  },
+  "include": ["lib/**/*.js"],
+  "exclude": ["node_modules"]
+}
diff --git a/release-please-config.json b/release-please-config.json
index cdf3e031..d21c0155 100644
--- a/release-please-config.json
+++ b/release-please-config.json
@@ -8,6 +8,9 @@
     },
     "packages/eslint-scope": {
       "release-type": "node"
+    },
+    "packages/eslint-visitor-keys": {
+      "release-type": "node"
     }
   }
 }