diff --git a/core-foundation-sys/src/lib.rs b/core-foundation-sys/src/lib.rs
index 48c0887..2ff6d31 100644
--- a/core-foundation-sys/src/lib.rs
+++ b/core-foundation-sys/src/lib.rs
@@ -38,5 +38,7 @@ pub mod set;
 pub mod string;
 pub mod timezone;
 pub mod url;
+#[cfg(target_os = "macos")]
+pub mod user_notification;
 pub mod uuid;
 pub mod mach_port;
diff --git a/core-foundation-sys/src/user_notification.rs b/core-foundation-sys/src/user_notification.rs
new file mode 100644
index 0000000..0e01856
--- /dev/null
+++ b/core-foundation-sys/src/user_notification.rs
@@ -0,0 +1,91 @@
+// Copyright 2023 The Servo Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use std::os::raw::c_void;
+
+use base::{CFOptionFlags, CFIndex, CFAllocatorRef, CFTypeID, SInt32};
+use dictionary::CFDictionaryRef;
+use string::CFStringRef;
+use date::CFTimeInterval;
+use runloop::CFRunLoopSourceRef;
+use url::CFURLRef;
+
+#[repr(C)]
+pub struct __CFUserNotification(c_void);
+
+pub type CFUserNotificationCallBack = extern "C" fn (userNotification: CFUserNotificationRef, responseFlags: CFOptionFlags);
+pub type CFUserNotificationRef = *mut __CFUserNotification;
+
+/* Alert Levels */
+pub const kCFUserNotificationStopAlertLevel: CFOptionFlags = 0;
+pub const kCFUserNotificationNoteAlertLevel: CFOptionFlags = 1;
+pub const kCFUserNotificationCautionAlertLevel: CFOptionFlags = 2;
+pub const kCFUserNotificationPlainAlertLevel: CFOptionFlags = 3;
+
+/* Response Codes */
+pub const kCFUserNotificationDefaultResponse: CFOptionFlags = 0;
+pub const kCFUserNotificationAlternateResponse: CFOptionFlags = 1;
+pub const kCFUserNotificationOtherResponse: CFOptionFlags = 2;
+pub const kCFUserNotificationCancelResponse: CFOptionFlags = 3;
+
+/* Button Flags */
+pub const kCFUserNotificationNoDefaultButtonFlag: CFOptionFlags = 1usize << 5;
+pub const kCFUserNotificationUseRadioButtonsFlag: CFOptionFlags = 1usize << 6;
+
+#[inline(always)]
+pub fn CFUserNotificationCheckBoxChecked(i: CFIndex) -> CFOptionFlags {
+    (1u32 << (8 + i)) as CFOptionFlags
+}
+
+#[inline(always)]
+pub fn CFUserNotificationSecureTextField(i: CFIndex) -> CFOptionFlags {
+    (1u32 << (16 + i)) as CFOptionFlags
+}
+
+#[inline(always)]
+pub fn CFUserNotificationPopUpSelection(n: CFIndex) -> CFOptionFlags {
+    (n << 24) as CFOptionFlags
+}
+
+
+extern {
+    /*
+     * CFUserNotification.h
+     */
+
+    /* Dialog Description Keys */
+    pub static kCFUserNotificationIconURLKey: CFStringRef;
+    pub static kCFUserNotificationSoundURLKey: CFStringRef;
+    pub static kCFUserNotificationLocalizationURLKey: CFStringRef;
+    pub static kCFUserNotificationAlertHeaderKey: CFStringRef;
+    pub static kCFUserNotificationAlertMessageKey: CFStringRef;
+    pub static kCFUserNotificationDefaultButtonTitleKey: CFStringRef;
+    pub static kCFUserNotificationAlternateButtonTitleKey: CFStringRef;
+    pub static kCFUserNotificationOtherButtonTitleKey: CFStringRef;
+    pub static kCFUserNotificationProgressIndicatorValueKey: CFStringRef;
+    pub static kCFUserNotificationPopUpTitlesKey: CFStringRef;
+    pub static kCFUserNotificationTextFieldTitlesKey: CFStringRef;
+    pub static kCFUserNotificationCheckBoxTitlesKey: CFStringRef;
+    pub static kCFUserNotificationTextFieldValuesKey: CFStringRef;
+    pub static kCFUserNotificationPopUpSelectionKey: CFStringRef;
+    pub static kCFUserNotificationAlertTopMostKey: CFStringRef;
+    pub static kCFUserNotificationKeyboardTypesKey: CFStringRef;
+
+    /* CFUserNotification Miscellaneous Functions */
+    pub fn CFUserNotificationCancel(userNotification: CFUserNotificationRef) -> SInt32;
+    pub fn CFUserNotificationCreate(allocator: CFAllocatorRef, timeout: CFTimeInterval, flags: CFOptionFlags, error: *mut SInt32, dictionary: CFDictionaryRef) -> CFUserNotificationRef;
+    pub fn CFUserNotificationCreateRunLoopSource(allocator: CFAllocatorRef, userNotification: CFUserNotificationRef, callout: CFUserNotificationCallBack, order: CFIndex) -> CFRunLoopSourceRef;
+    pub fn CFUserNotificationDisplayAlert(timeout: CFTimeInterval, flags: CFOptionFlags, iconURL: CFURLRef, soundURL: CFURLRef, localizationURL: CFURLRef, alertHeader: CFStringRef, alertMessage: CFStringRef, defaultButtonTitle: CFStringRef, alternateButtonTitle: CFStringRef, otherButtonTitle: CFStringRef, responseFlags: *mut CFOptionFlags) -> SInt32;
+    pub fn CFUserNotificationDisplayNotice(timeout: CFTimeInterval, flags: CFOptionFlags, iconURL: CFURLRef, soundURL: CFURLRef, localizationURL: CFURLRef, alertHeader: CFStringRef, alertMessage: CFStringRef, defaultButtonTitle: CFStringRef) -> SInt32;
+    pub fn CFUserNotificationGetTypeID() -> CFTypeID;
+    pub fn CFUserNotificationGetResponseDictionary(userNotification: CFUserNotificationRef) -> CFDictionaryRef;
+    pub fn CFUserNotificationGetResponseValue(userNotification: CFUserNotificationRef, key: CFStringRef, idx: CFIndex) -> CFStringRef;
+    pub fn CFUserNotificationReceiveResponse(userNotification: CFUserNotificationRef, timeout: CFTimeInterval, responseFlags: *mut CFOptionFlags) -> SInt32;
+    pub fn CFUserNotificationUpdate(userNotification: CFUserNotificationRef, timeout: CFTimeInterval, flags: CFOptionFlags, dictionary: CFDictionaryRef) -> SInt32;
+}