diff --git a/packages/headers/CHANGELOG.md b/packages/headers/CHANGELOG.md
index 2994d87..475479b 100644
--- a/packages/headers/CHANGELOG.md
+++ b/packages/headers/CHANGELOG.md
@@ -2,6 +2,11 @@
 
 This is the changelog for [`headers`](https://github.com/mjackson/remix-the-web/tree/main/packages/headers). It follows [semantic versioning](https://semver.org/).
 
+## HEAD
+
+- BREAKING CHANGE: `cookie.delete(name)` returns `void` instead of `boolean`
+- BREAKING CHANGE: `cookie.forEach()` calls its callback with `(name, value, cookie)` instead of `(value, name, map)`
+
 ## v0.9.0 (2024-12-20)
 
 This release tightens up the type safety and brings `SuperHeaders` more in line with the built-in `Headers` interface.
diff --git a/packages/headers/src/lib/cookie.test.ts b/packages/headers/src/lib/cookie.test.ts
index 3d2d35b..7367bfe 100644
--- a/packages/headers/src/lib/cookie.test.ts
+++ b/packages/headers/src/lib/cookie.test.ts
@@ -43,16 +43,21 @@ describe('Cookie', () => {
   });
 
   it('sets and gets values', () => {
-    let header = new Cookie('');
+    let header = new Cookie();
     header.set('name', 'value');
     assert.equal(header.get('name'), 'value');
   });
 
+  it('returns `null` for nonexistent values', () => {
+    let header = new Cookie();
+    assert.equal(header.get('name'), null);
+  });
+
   it('deletes values', () => {
     let header = new Cookie('name=value');
-    assert.equal(header.delete('name'), true);
-    assert.equal(header.delete('nonexistent'), false);
-    assert.equal(header.get('name'), undefined);
+    assert.equal(header.has('name'), true);
+    header.delete('name');
+    assert.equal(header.has('name'), false);
   });
 
   it('checks if value exists', () => {
@@ -63,19 +68,11 @@ describe('Cookie', () => {
 
   it('clears all values', () => {
     let header = new Cookie('name1=value1; name2=value2');
+    assert.equal(header.size, 2);
     header.clear();
     assert.equal(header.size, 0);
   });
 
-  it('iterates over entries', () => {
-    let header = new Cookie('name1=value1; name2=value2');
-    let entries = Array.from(header.entries());
-    assert.deepEqual(entries, [
-      ['name1', 'value1'],
-      ['name2', 'value2'],
-    ]);
-  });
-
   it('iterates over names', () => {
     let header = new Cookie('name1=value1; name2=value2');
     let names = Array.from(header.names());
@@ -88,10 +85,19 @@ describe('Cookie', () => {
     assert.deepEqual(values, ['value1', 'value2']);
   });
 
+  it('iterates over entries', () => {
+    let header = new Cookie('name1=value1; name2=value2');
+    let entries = Array.from(header.entries());
+    assert.deepEqual(entries, [
+      ['name1', 'value1'],
+      ['name2', 'value2'],
+    ]);
+  });
+
   it('uses forEach correctly', () => {
     let header = new Cookie('name1=value1; name2=value2');
     let result: [string, string][] = [];
-    header.forEach((value, name) => {
+    header.forEach((name, value) => {
       result.push([name, value]);
     });
     assert.deepEqual(result, [
diff --git a/packages/headers/src/lib/cookie.ts b/packages/headers/src/lib/cookie.ts
index 3bfd8da..2d327b0 100644
--- a/packages/headers/src/lib/cookie.ts
+++ b/packages/headers/src/lib/cookie.ts
@@ -37,44 +37,47 @@ export class Cookie implements HeaderValue, Iterable<[string, string]> {
   }
 
   /**
-   * Gets the value of a cookie with the given name from the `Cookie` header.
+   * Gets the value of a cookie with the given name from the header.
+   * @param name The name of the cookie.
+   * @returns The value of the cookie, or `null` if the cookie does not exist.
    */
-  get(name: string): string | undefined {
-    return this.#map.get(name);
+  get(name: string): string | null {
+    return this.#map.get(name) ?? null;
   }
 
   /**
-   * Sets a cookie with the given name and value in the `Cookie` header.
+   * Sets a cookie with the given name and value in the header.
+   * @param name The name of the cookie.
+   * @param value The value of the cookie.
    */
   set(name: string, value: string): void {
     this.#map.set(name, value);
   }
 
   /**
-   * Removes a cookie with the given name from the `Cookie` header.
+   * Removes a cookie with the given name from the header.
+   * @param name The name of the cookie.
    */
-  delete(name: string): boolean {
-    return this.#map.delete(name);
+  delete(name: string): void {
+    this.#map.delete(name);
   }
 
   /**
-   * True if a cookie with the given name exists in the `Cookie` header.
+   * True if a cookie with the given name exists in the header.
+   * @param name The name of the cookie.
+   * @returns True if a cookie with the given name exists in the header.
    */
   has(name: string): boolean {
     return this.#map.has(name);
   }
 
   /**
-   * Removes all cookies from the `Cookie` header.
+   * Removes all cookies from the header.
    */
   clear(): void {
     this.#map.clear();
   }
 
-  entries(): IterableIterator<[string, string]> {
-    return this.#map.entries();
-  }
-
   names(): IterableIterator<string> {
     return this.#map.keys();
   }
@@ -83,19 +86,22 @@ export class Cookie implements HeaderValue, Iterable<[string, string]> {
     return this.#map.values();
   }
 
+  entries(): IterableIterator<[string, string]> {
+    return this.#map.entries();
+  }
+
   [Symbol.iterator](): IterableIterator<[string, string]> {
     return this.entries();
   }
 
-  forEach(
-    callback: (value: string, key: string, map: Map<string, string>) => void,
-    thisArg?: any,
-  ): void {
-    this.#map.forEach(callback, thisArg);
+  forEach(callback: (name: string, value: string, header: Cookie) => void, thisArg?: any): void {
+    for (let [name, value] of this) {
+      callback.call(thisArg, name, value, this);
+    }
   }
 
   /**
-   * The number of cookies in the `Cookie` header.
+   * The number of cookies in the header.
    */
   get size(): number {
     return this.#map.size;