diff --git a/Sources/NIOCore/EventLoop+SerialExecutor.swift b/Sources/NIOCore/EventLoop+SerialExecutor.swift
index 6453452bde..865ce769cd 100644
--- a/Sources/NIOCore/EventLoop+SerialExecutor.swift
+++ b/Sources/NIOCore/EventLoop+SerialExecutor.swift
@@ -86,10 +86,10 @@ extension NIODefaultEventLoopExecutor: SerialExecutor {
 ///
 /// Implementers of `EventLoop` should consider conforming to this protocol as
 /// well on Swift 6.0 and later.
-@available(macOS 9999.0, iOS 9999.0, watchOS 9999.0, tvOS 9999.0, *)
+@available(macOS 15.0, iOS 18.0, tvOS 18.0, watchOS 11.0, *)
 public protocol NIOTaskEventLoopExecutor: NIOSerialEventLoopExecutor & TaskExecutor { }
 
-@available(macOS 9999.0, iOS 9999.0, watchOS 9999.0, tvOS 9999.0, *)
+@available(macOS 15.0, iOS 18.0, tvOS 18.0, watchOS 11.0, *)
 extension NIOTaskEventLoopExecutor {
     @inlinable
     func asUnownedTaskExecutor() -> UnownedTaskExecutor {
@@ -102,7 +102,7 @@ extension NIOTaskEventLoopExecutor {
     }
 }
 
-@available(macOS 9999.0, iOS 9999.0, watchOS 9999.0, tvOS 9999.0, *)
+@available(macOS 15.0, iOS 18.0, tvOS 18.0, watchOS 11.0, *)
 extension NIODefaultEventLoopExecutor: TaskExecutor {
     @inlinable
     public func asUnownedTaskExecutor() -> UnownedTaskExecutor {
diff --git a/Sources/NIOCore/EventLoop.swift b/Sources/NIOCore/EventLoop.swift
index 45dfa8ff52..62ad3cf071 100644
--- a/Sources/NIOCore/EventLoop.swift
+++ b/Sources/NIOCore/EventLoop.swift
@@ -400,7 +400,7 @@ extension EventLoop {
     #endif
 
     #if compiler(>=6.0)
-    @available(macOS 9999.0, iOS 9999.0, watchOS 9999.0, tvOS 9999.0, *)
+    @available(macOS 15.0, iOS 9999.0, watchOS 9999.0, tvOS 9999.0, *)
     public var taskExecutor: any TaskExecutor {
         NIODefaultEventLoopExecutor(self)
     }
diff --git a/Sources/NIOEmbedded/AsyncTestingEventLoop.swift b/Sources/NIOEmbedded/AsyncTestingEventLoop.swift
index 58f20b6bd0..8bca6bbfa6 100644
--- a/Sources/NIOEmbedded/AsyncTestingEventLoop.swift
+++ b/Sources/NIOEmbedded/AsyncTestingEventLoop.swift
@@ -357,7 +357,7 @@ extension NIOAsyncTestingEventLoop: NIOSerialEventLoopExecutor { }
 
 // MARK: TaskExecutor conformance
 #if compiler(>=6.0)
-@available(macOS 9999.0, iOS 9999.0, watchOS 9999.0, tvOS 9999.0, *)
+@available(macOS 15.0, iOS 18.0, tvOS 18.0, watchOS 11.0, *)
 extension NIOAsyncTestingEventLoop: NIOTaskEventLoopExecutor { }
 #endif
 
diff --git a/Sources/NIOEmbedded/Embedded.swift b/Sources/NIOEmbedded/Embedded.swift
index 9e2eb23cdf..fee4d60d43 100644
--- a/Sources/NIOEmbedded/Embedded.swift
+++ b/Sources/NIOEmbedded/Embedded.swift
@@ -242,7 +242,7 @@ public final class EmbeddedEventLoop: EventLoop {
     #endif
 
     #if compiler(>=6.0)
-    @available(macOS 9999.0, iOS 9999.0, watchOS 9999.0, tvOS 9999.0, *)
+    @available(macOS 15.0, iOS 18.0, tvOS 18.0, watchOS 11.0, *)
     public var taskExecutor: any TaskExecutor {
         fatalError("EmbeddedEventLoop is not thread safe and cannot be used as a TaskExecutor. Use NIOAsyncTestingEventLoop instead.")
     }
diff --git a/Sources/NIOPosix/SelectableEventLoop.swift b/Sources/NIOPosix/SelectableEventLoop.swift
index da32500213..2da4e2a816 100644
--- a/Sources/NIOPosix/SelectableEventLoop.swift
+++ b/Sources/NIOPosix/SelectableEventLoop.swift
@@ -886,6 +886,6 @@ internal func assertExpression(_ body: () -> Bool) {
 
 // MARK: TaskExecutor conformance
 #if compiler(>=6.0)
-@available(macOS 9999.0, iOS 9999.0, watchOS 9999.0, tvOS 9999.0, *)
+@available(macOS 15.0, iOS 18.0, tvOS 18.0, watchOS 11.0, *)
 extension SelectableEventLoop: NIOTaskEventLoopExecutor { }
 #endif
diff --git a/Tests/NIOPosixTests/TaskExecutorTests.swift b/Tests/NIOPosixTests/TaskExecutorTests.swift
index bd8cf4bc84..a245ef4c5f 100644
--- a/Tests/NIOPosixTests/TaskExecutorTests.swift
+++ b/Tests/NIOPosixTests/TaskExecutorTests.swift
@@ -19,7 +19,7 @@ import XCTest
 final class TaskExecutorTests: XCTestCase {
 
     #if compiler(>=6.0)
-    @available(macOS 9999.0, iOS 9999.0, watchOS 9999.0, tvOS 9999.0, *)
+    @available(macOS 15.0, iOS 18.0, tvOS 18.0, watchOS 11.0, *)
     func _runTests(loop1: some EventLoop, loop2: some EventLoop) async {
         await withTaskGroup(of: Void.self) { taskGroup in
             taskGroup.addTask(executorPreference: loop1.taskExecutor) {
@@ -57,7 +57,7 @@ final class TaskExecutorTests: XCTestCase {
     }
     #endif
 
-    @available(macOS 9999.0, iOS 9999.0, watchOS 9999.0, tvOS 9999.0, *)
+    @available(macOS 15.0, iOS 18.0, tvOS 18.0, watchOS 11.0, *)
     func testSelectableEventLoopAsTaskExecutor() async throws {
         #if compiler(>=6.0)
         let group = MultiThreadedEventLoopGroup(numberOfThreads: 2)
@@ -72,7 +72,7 @@ final class TaskExecutorTests: XCTestCase {
         #endif
     }
 
-    @available(macOS 9999.0, iOS 9999.0, watchOS 9999.0, tvOS 9999.0, *)
+    @available(macOS 15.0, iOS 18.0, tvOS 18.0, watchOS 11.0, *)
     func testAsyncTestingEventLoopAsTaskExecutor() async throws {
         #if compiler(>=6.0)
         let loop1 = NIOAsyncTestingEventLoop()