diff --git a/packages/cookie-store/src/CookieStore.ts b/packages/cookie-store/src/CookieStore.ts
index 126e5c87fa4..c524682676d 100644
--- a/packages/cookie-store/src/CookieStore.ts
+++ b/packages/cookie-store/src/CookieStore.ts
@@ -22,7 +22,7 @@ export class CookieStore extends EventTarget {
   }
 
   async get(
-    init?: CookieStoreGetOptions['name'] | CookieStoreGetOptions,
+    init?: CookieStoreGetOptions['name'] | CookieStoreGetOptions | undefined,
   ): Promise<Cookie | undefined> {
     if (init == null) {
       throw new TypeError('CookieStoreGetOptions must not be empty');
diff --git a/packages/cookie-store/src/types.ts b/packages/cookie-store/src/types.ts
index 76d92122aae..ba2a90c6b00 100644
--- a/packages/cookie-store/src/types.ts
+++ b/packages/cookie-store/src/types.ts
@@ -16,21 +16,21 @@ export interface CookieStoreDeleteOptions {
 }
 
 export interface CookieStoreGetOptions {
-  name?: string;
+  name?: string | undefined;
   url?: string;
 }
 
 export type CookieSameSite = 'strict' | 'lax' | 'none';
 
 export interface CookieListItem {
-  name?: string;
-  value?: string;
+  name?: string | undefined;
+  value?: string | undefined;
   domain: string | null;
-  path?: string;
+  path?: string | undefined;
   expires: Date | number | null;
-  secure?: boolean;
-  sameSite?: CookieSameSite;
-  httpOnly?: boolean;
+  secure?: boolean | undefined;
+  sameSite?: CookieSameSite | undefined;
+  httpOnly?: boolean | undefined;
 }
 
 export type CookieList = CookieListItem[];
diff --git a/packages/disposablestack/src/AsyncDisposableStack.ts b/packages/disposablestack/src/AsyncDisposableStack.ts
index 128f3b48af4..602bd666551 100644
--- a/packages/disposablestack/src/AsyncDisposableStack.ts
+++ b/packages/disposablestack/src/AsyncDisposableStack.ts
@@ -43,7 +43,7 @@ export class PonyfillAsyncDisposableStack implements AsyncDisposableStack {
     return this[DisposableSymbols.asyncDispose]();
   }
 
-  private _error?: Error;
+  private _error?: Error | undefined;
 
   private _iterateCallbacks(): MaybePromise<void> {
     const cb = this.callbacks.pop();
diff --git a/packages/disposablestack/src/DisposableStack.ts b/packages/disposablestack/src/DisposableStack.ts
index d77e87e6134..43fec12762b 100644
--- a/packages/disposablestack/src/DisposableStack.ts
+++ b/packages/disposablestack/src/DisposableStack.ts
@@ -41,7 +41,7 @@ export class PonyfillDisposableStack implements DisposableStack {
     return this[DisposableSymbols.dispose]();
   }
 
-  private _error?: Error;
+  private _error?: Error | undefined;
 
   private _iterateCallbacks(): void {
     const cb = this.callbacks.pop();
diff --git a/packages/node-fetch/src/Body.ts b/packages/node-fetch/src/Body.ts
index 88b1dd29e61..840def2800e 100644
--- a/packages/node-fetch/src/Body.ts
+++ b/packages/node-fetch/src/Body.ts
@@ -60,11 +60,11 @@ export class PonyfillBody<TJSON = any> implements Body {
     this._buffer = buffer;
   }
 
-  private bodyType?: BodyInitType;
+  private bodyType?: BodyInitType | undefined;
 
   private _bodyFactory: () => PonyfillReadableStream<Uint8Array> | null = () => null;
   private _generatedBody: PonyfillReadableStream<Uint8Array> | null = null;
-  private _buffer?: Buffer;
+  private _buffer?: Buffer | undefined;
 
   private generateBody(): PonyfillReadableStream<Uint8Array> | null {
     if (this._generatedBody?.readable?.destroyed && this._buffer) {
diff --git a/packages/node-fetch/src/Request.ts b/packages/node-fetch/src/Request.ts
index 0f4e951699e..221f8916188 100644
--- a/packages/node-fetch/src/Request.ts
+++ b/packages/node-fetch/src/Request.ts
@@ -10,11 +10,11 @@ function isRequest(input: any): input is PonyfillRequest {
 
 export type RequestPonyfillInit = PonyfillBodyOptions &
   Omit<RequestInit, 'body' | 'headers'> & {
-    body?: BodyPonyfillInit | null;
-    duplex?: 'half' | 'full';
-    headers?: PonyfillHeadersInit;
-    headersSerializer?: HeadersSerializer;
-    agent?: HTTPAgent | HTTPSAgent | false;
+    body?: BodyPonyfillInit | null | undefined;
+    duplex?: 'half' | 'full' | undefined;
+    headers?: PonyfillHeadersInit | undefined;
+    headersSerializer?: HeadersSerializer | undefined;
+    agent?: HTTPAgent | HTTPSAgent | false | undefined;
   };
 
 type HeadersSerializer = (
@@ -96,7 +96,7 @@ export class PonyfillRequest<TJSON = any> extends PonyfillBody<TJSON> implements
     }
   }
 
-  headersSerializer?: HeadersSerializer;
+  headersSerializer?: HeadersSerializer | undefined;
   cache: RequestCache;
   credentials: RequestCredentials;
   destination: RequestDestination;
diff --git a/packages/node-fetch/src/Response.ts b/packages/node-fetch/src/Response.ts
index 958ef7251e7..44d06e731e5 100644
--- a/packages/node-fetch/src/Response.ts
+++ b/packages/node-fetch/src/Response.ts
@@ -4,10 +4,10 @@ import { isHeadersLike, PonyfillHeaders, PonyfillHeadersInit } from './Headers.j
 
 export type ResponsePonyfilInit = PonyfillBodyOptions &
   Omit<ResponseInit, 'headers'> & {
-    url?: string;
-    redirected?: boolean;
-    headers?: PonyfillHeadersInit;
-    type?: ResponseType;
+    url?: string | undefined;
+    redirected?: boolean | undefined;
+    headers?: PonyfillHeadersInit | undefined;
+    type?: ResponseType | undefined;
   };
 
 const JSON_CONTENT_TYPE = 'application/json; charset=utf-8';
@@ -15,7 +15,7 @@ const JSON_CONTENT_TYPE = 'application/json; charset=utf-8';
 export class PonyfillResponse<TJSON = any> extends PonyfillBody<TJSON> implements Response {
   headers: Headers;
 
-  constructor(body?: BodyPonyfillInit | null, init?: ResponsePonyfilInit) {
+  constructor(body?: BodyPonyfillInit | null | undefined, init?: ResponsePonyfilInit) {
     super(body || null, init);
     this.headers =
       init?.headers && isHeadersLike(init.headers)
diff --git a/packages/node-fetch/src/fetchNodeHttp.ts b/packages/node-fetch/src/fetchNodeHttp.ts
index 7993eb9f92f..61259e29baf 100644
--- a/packages/node-fetch/src/fetchNodeHttp.ts
+++ b/packages/node-fetch/src/fetchNodeHttp.ts
@@ -1,4 +1,4 @@
-import { request as httpRequest } from 'http';
+import { request as httpRequest, STATUS_CODES } from 'http';
 import { request as httpsRequest } from 'https';
 import { PassThrough, Readable, promises as streamPromises } from 'stream';
 import { createBrotliDecompress, createGunzip, createInflate, createInflateRaw } from 'zlib';
@@ -124,9 +124,14 @@ export function fetchNodeHttp<TResponseJSON = any, TRequestJSON = any>(
           })
           .catch(reject);
 
+        const statusCode = nodeResponse.statusCode || 200;
+        let statusText = nodeResponse.statusMessage || STATUS_CODES[statusCode];
+        if (statusText == null) {
+          statusText = '';
+        }
         const ponyfillResponse = new PonyfillResponse(outputStream, {
-          status: nodeResponse.statusCode,
-          statusText: nodeResponse.statusMessage,
+          status: statusCode,
+          statusText,
           headers: nodeResponse.headers as Record<string, string>,
           url: fetchRequest.url,
         });
diff --git a/packages/server/src/utils.ts b/packages/server/src/utils.ts
index 77e0f0cebc6..4c3302d4cc0 100644
--- a/packages/server/src/utils.ts
+++ b/packages/server/src/utils.ts
@@ -11,19 +11,19 @@ export function isAsyncIterable(body: any): body is AsyncIterable<any> {
 }
 
 export interface NodeRequest {
-  protocol?: string;
-  hostname?: string;
-  body?: any;
-  url?: string;
-  originalUrl?: string;
-  method?: string;
-  headers?: any;
-  req?: IncomingMessage | Http2ServerRequest;
-  raw?: IncomingMessage | Http2ServerRequest;
-  socket?: Socket;
-  query?: any;
+  protocol?: string | undefined;
+  hostname?: string | undefined;
+  body?: any | undefined;
+  url?: string | undefined;
+  originalUrl?: string | undefined;
+  method?: string | undefined;
+  headers?: any | undefined;
+  req?: IncomingMessage | Http2ServerRequest | undefined;
+  raw?: IncomingMessage | Http2ServerRequest | undefined;
+  socket?: Socket | undefined;
+  query?: any | undefined;
   once?(event: string, listener: (...args: any[]) => void): void;
-  aborted?: boolean;
+  aborted?: boolean | undefined;
 }
 
 export type NodeResponse = ServerResponse | Http2ServerResponse;
@@ -183,7 +183,7 @@ export function normalizeNodeRequest(
     return new fetchAPI.Request(fullUrl, {
       method: nodeRequest.method,
       headers: normalizedHeaders,
-      signal,
+      signal: signal || null,
     });
   }
 
@@ -197,16 +197,16 @@ export function normalizeNodeRequest(
   if (maybeParsedBody != null && Object.keys(maybeParsedBody).length > 0) {
     if (isRequestBody(maybeParsedBody)) {
       return new fetchAPI.Request(fullUrl, {
-        method: nodeRequest.method,
+        method: nodeRequest.method || 'GET',
         headers: normalizedHeaders,
         body: maybeParsedBody,
-        signal,
+        signal: signal || null,
       });
     }
     const request = new fetchAPI.Request(fullUrl, {
-      method: nodeRequest.method,
+      method: nodeRequest.method || 'GET',
       headers: normalizedHeaders,
-      signal,
+      signal: signal || null,
     });
     if (!request.headers.get('content-type')?.includes('json')) {
       request.headers.set('content-type', 'application/json; charset=utf-8');
diff --git a/tsconfig.json b/tsconfig.json
index 9f595c3ff3e..ca315771499 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -15,6 +15,7 @@
     "declaration": true,
     "downlevelIteration": true,
     "incremental": true,
+    "exactOptionalPropertyTypes": true,
 
     "skipLibCheck": false,