diff --git a/Package.swift b/Package.swift
index 7e1dba2..9c1203c 100644
--- a/Package.swift
+++ b/Package.swift
@@ -1,4 +1,4 @@
-// swift-tools-version: 5.6
+// swift-tools-version: 5.8
 
 import PackageDescription
 
@@ -20,3 +20,13 @@ let package = Package(
 		.testTarget(name: "NSUITests", dependencies: ["NSUI"]),
 	]
 )
+
+let swiftSettings: [SwiftSetting] = [
+	.enableExperimentalFeature("StrictConcurrency"),
+]
+
+for target in package.targets {
+	var settings = target.swiftSettings ?? []
+	settings.append(contentsOf: swiftSettings)
+	target.swiftSettings = settings
+}
diff --git a/Sources/NSUI/ViewRepresentable.swift b/Sources/NSUI/ViewRepresentable.swift
index ae1138d..d5c482a 100644
--- a/Sources/NSUI/ViewRepresentable.swift
+++ b/Sources/NSUI/ViewRepresentable.swift
@@ -6,15 +6,19 @@ import AppKit
 public protocol NSUIViewRepresentable: NSViewRepresentable {
 	associatedtype NSUIViewType: NSView
 
+	@MainActor
 	func makeNSUIView(context: Context) -> NSUIViewType
+	@MainActor
 	func updateNSUIView(_ view: NSUIViewType, context: Context)
 }
 
 public extension NSUIViewRepresentable {
+	@MainActor
 	func makeNSView(context: Context) -> NSUIViewType {
 		makeNSUIView(context: context)
 	}
 
+	@MainActor
 	func updateNSView(_ view: NSUIViewType, context: Context) {
 		updateNSUIView(view, context: context)
 	}
@@ -26,15 +30,19 @@ import UIKit
 public protocol NSUIViewRepresentable: UIViewRepresentable {
 	associatedtype NSUIViewType: UIView
 
+	@MainActor
 	func makeNSUIView(context: Context) -> NSUIViewType
+	@MainActor
 	func updateNSUIView(_ view: NSUIViewType, context: Context)
 }
 
 public extension NSUIViewRepresentable {
+	@MainActor
 	func makeUIView(context: Context) -> NSUIViewType {
 		makeNSUIView(context: context)
 	}
 
+	@MainActor
 	func updateUIView(_ view: NSUIViewType, context: Context) {
 		updateNSUIView(view, context: context)
 	}
diff --git a/Tests/NSUITests/ControllerTests.swift b/Tests/NSUITests/ControllerTests.swift
index c6a1a83..a2962c9 100644
--- a/Tests/NSUITests/ControllerTests.swift
+++ b/Tests/NSUITests/ControllerTests.swift
@@ -5,6 +5,7 @@ final class MyController: NSUIViewController {
 }
 
 final class ControllerTests: XCTestCase {
+	@MainActor
 	func testControllerClassDefinition() throws {
 		let _ = MyController()
 	}
diff --git a/Tests/NSUITests/TextViewTests.swift b/Tests/NSUITests/TextViewTests.swift
index 47384b3..323a57f 100644
--- a/Tests/NSUITests/TextViewTests.swift
+++ b/Tests/NSUITests/TextViewTests.swift
@@ -2,6 +2,7 @@ import XCTest
 @testable import NSUI
 
 final class TextViewTests: XCTestCase {
+	@MainActor
     func testTextViewText() throws {
         let textView = NSUITextView()
 
@@ -10,6 +11,7 @@ final class TextViewTests: XCTestCase {
 		XCTAssertEqual(textView.text, "abc")
     }
 
+	@MainActor
 	func testEditActions() throws {
 		let edit = NSUITextStorageEditActions.editedAttributes
 
diff --git a/Tests/NSUITests/ViewRepresentableTests.swift b/Tests/NSUITests/ViewRepresentableTests.swift
index f5a9b82..397e9a2 100644
--- a/Tests/NSUITests/ViewRepresentableTests.swift
+++ b/Tests/NSUITests/ViewRepresentableTests.swift
@@ -1,6 +1,7 @@
 import XCTest
 @testable import NSUI
 
+@MainActor
 struct RepresentedView: NSUIViewRepresentable {
 	typealias NSUIViewType = NSUIView