diff --git a/.changeset/pink-flowers-wait.md b/.changeset/pink-flowers-wait.md
new file mode 100644
index 0000000..a2faae3
--- /dev/null
+++ b/.changeset/pink-flowers-wait.md
@@ -0,0 +1,5 @@
+---
+'fetch-nodeshim': minor
+---
+
+Add web standard type/globals re-exports and polyfill `File` from `node:buffer`.
diff --git a/package.json b/package.json
index 4692da7..215cac5 100644
--- a/package.json
+++ b/package.json
@@ -64,7 +64,7 @@
     "rollup-plugin-cjs-check": "^1.0.3",
     "rollup-plugin-dts": "^6.1.1",
     "typescript": "^5.7.3",
-    "undici-types": "^7.3.0",
+    "undici-types": "^6.20.0",
     "vitest": "^3.0.4"
   }
 }
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index cac16e8..bc2449e 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -69,8 +69,8 @@ importers:
         specifier: ^5.7.3
         version: 5.7.3
       undici-types:
-        specifier: ^7.3.0
-        version: 7.3.0
+        specifier: ^6.20.0
+        version: 6.20.0
       vitest:
         specifier: ^3.0.4
         version: 3.0.4(@types/node@22.12.0)(terser@5.37.0)(yaml@2.7.0)
@@ -1911,9 +1911,6 @@ packages:
   undici-types@6.20.0:
     resolution: {integrity: sha512-Ny6QZ2Nju20vw1SRHe3d9jVu6gJ+4e3+MMpqu7pqE5HT6WsTSlce++GQmK5UXS8mzV8DSYHrQH+Xrf2jVcuKNg==}
 
-  undici-types@7.3.0:
-    resolution: {integrity: sha512-z2pHpkN2BEJl3QlQo0GtfGCyuhuBbWX60vzGwyn7ex/seM2UkvyGEfEV0Qb9pXc5StNfcJpsstgaf2YTEJa63Q==}
-
   universalify@0.1.2:
     resolution: {integrity: sha512-rBJeI5CXAlmy1pV+617WB9J63U6XcazHHF2f2dbJix4XzpUF0RS3Zbj0FGIOCAva5P/d/GBOYaACQ1w+0azUkg==}
     engines: {node: '>= 4.0.0'}
@@ -4032,8 +4029,6 @@ snapshots:
 
   undici-types@6.20.0: {}
 
-  undici-types@7.3.0: {}
-
   universalify@0.1.2: {}
 
   update-browserslist-db@1.1.2(browserslist@4.24.4):
diff --git a/src/fetch.ts b/src/fetch.ts
index d7b42d2..78d42be 100644
--- a/src/fetch.ts
+++ b/src/fetch.ts
@@ -5,6 +5,7 @@ import * as url from 'node:url';
 
 import { extractBody } from './body';
 import { createContentDecoder } from './encoding';
+import { URL, Request, RequestInit, Response } from './webstd';
 
 /** Maximum allowed redirects (matching Chromium's limit) */
 const MAX_REDIRECTS = 20;
@@ -102,7 +103,7 @@ function createResponse(
   return response;
 }
 
-export async function fetch(
+async function _fetch(
   input: string | URL | Request,
   requestInit?: RequestInit
 ): Promise<Response> {
@@ -131,7 +132,7 @@ export async function fetch(
     signal,
   } satisfies http.RequestOptions;
 
-  function _fetch(
+  function _call(
     resolve: (response: Response | Promise<Response>) => void,
     reject: (reason?: any) => void
   ) {
@@ -196,7 +197,7 @@ export async function fetch(
             requestOptions,
             urlToHttpOptions((requestUrl = locationURL))
           );
-          return _fetch(resolve, reject);
+          return _call(resolve, reject);
         }
       }
 
@@ -258,5 +259,7 @@ export async function fetch(
     }
   }
 
-  return await new Promise(_fetch);
+  return await new Promise(_call);
 }
+
+export { _fetch as fetch };
diff --git a/src/index.ts b/src/index.ts
index 6f95cf1..00fba55 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1 +1,2 @@
 export { fetch, fetch as default } from './fetch';
+export * from './webstd';
diff --git a/src/webstd.ts b/src/webstd.ts
new file mode 100644
index 0000000..84caf4b
--- /dev/null
+++ b/src/webstd.ts
@@ -0,0 +1,81 @@
+/// <reference types="@types/node" />
+
+import * as buffer from 'node:buffer';
+
+type Or<T, U> = void extends T ? U : T;
+
+export type BodyInit =
+  | ArrayBuffer
+  | AsyncIterable<Uint8Array>
+  | Blob
+  | FormData
+  | Iterable<Uint8Array>
+  | NodeJS.ArrayBufferView
+  | URLSearchParams
+  | null
+  | string;
+
+// See: https://nodejs.org/docs/latest-v20.x/api/globals.html#class-file
+// The `File` global was only added in Node.js 20
+interface _File extends Or<File, globalThis.File> {}
+const _File: Or<typeof File, typeof buffer.File> = buffer.File;
+if (typeof globalThis.File === 'undefined') {
+  globalThis.File = _File;
+}
+
+declare global {
+  var File: typeof _File;
+
+  // NOTE: In case undici was used, but its types aren't applied, this needs to be added
+  interface RequestInit {
+    duplex?: 'half';
+  }
+}
+
+// There be dragons here.
+// This is complex because of overlapping definitions in lib.dom, @types/node, and undici-types
+// Some types define and overload constructor interfaces with type interfaces
+// Here, we have to account for global differences and split the overloads apart
+
+interface _RequestInit extends Or<RequestInit, globalThis.RequestInit> {}
+interface _ResponseInit extends Or<ResponseInit, globalThis.ResponseInit> {}
+
+interface _URLSearchParams
+  extends Or<URLSearchParams, globalThis.URLSearchParams> {}
+interface URLSearchParamsClass
+  extends Or<typeof URLSearchParams, typeof globalThis.URLSearchParams> {}
+const _URLSearchParams: URLSearchParamsClass = URLSearchParams as any;
+
+interface _URL extends Or<URL, globalThis.URL> {}
+interface URLClass extends Or<typeof URL, typeof globalThis.URL> {}
+const _URL: URLClass = URL;
+
+interface _Request extends Or<Request, globalThis.Request> {}
+interface RequestClass extends Or<typeof Request, typeof globalThis.Request> {}
+const _Request: RequestClass = Request;
+
+interface _Response extends Or<Response, globalThis.Response> {}
+interface ResponseClass
+  extends Or<typeof Response, typeof globalThis.Response> {}
+const _Response: ResponseClass = Response;
+
+interface _Headers extends Or<Headers, globalThis.Headers> {}
+interface HeadersClass extends Or<typeof Headers, typeof globalThis.Headers> {}
+const _Headers: HeadersClass = Headers;
+
+interface _FormData extends Or<FormData, globalThis.FormData> {}
+interface FormDataClass
+  extends Or<typeof FormData, typeof globalThis.FormData> {}
+const _FormData: FormDataClass = FormData;
+
+export {
+  type _RequestInit as RequestInit,
+  type _ResponseInit as ResponseInit,
+  _File as File,
+  _URL as URL,
+  _URLSearchParams as URLSearchParams,
+  _Request as Request,
+  _Response as Response,
+  _Headers as Headers,
+  _FormData as FormData,
+};