diff --git a/Package.swift b/Package.swift
index fa3b1836..090ffcd3 100644
--- a/Package.swift
+++ b/Package.swift
@@ -23,7 +23,7 @@ let package = Package(
     dependencies: .init {
         Package.Dependency.package(url: "https://github.com/apple/swift-async-algorithms.git", from: "1.0.0")
         Package.Dependency.package(url: "https://github.com/nicklockwood/SwiftFormat.git", from: "0.54.1")
-        Package.Dependency.package(url: "https://github.com/apple/swift-syntax.git", exact: "600.0.0-prerelease-2024-06-12")
+        Package.Dependency.package(url: "https://github.com/swiftlang/swift-syntax.git", exact: "600.0.0-prerelease-2024-06-12")
 
 #if os(Linux)
         // Linux does not come bundled with swift-testing
diff --git a/Sources/Vexil/Sources/UserDefaults+FlagValueSource.swift b/Sources/Vexil/Sources/UserDefaults+FlagValueSource.swift
index d2a5d4a3..802de377 100644
--- a/Sources/Vexil/Sources/UserDefaults+FlagValueSource.swift
+++ b/Sources/Vexil/Sources/UserDefaults+FlagValueSource.swift
@@ -11,6 +11,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+#if !os(Linux)
+
 #if canImport(AppKit)
 import AppKit
 #endif
@@ -145,3 +147,5 @@ private extension Any? {
         return ObjectIdentifier(self) == object
     }
 }
+
+#endif // !os(Linux)
diff --git a/Tests/VexilTests/UserDefaultsDecodingTests.swift b/Tests/VexilTests/UserDefaultsDecodingTests.swift
index 4245d27c..741d825f 100644
--- a/Tests/VexilTests/UserDefaultsDecodingTests.swift
+++ b/Tests/VexilTests/UserDefaultsDecodingTests.swift
@@ -11,6 +11,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+#if !os(Linux)
+
 import Foundation
 import Testing
 @testable import Vexil
@@ -330,3 +332,5 @@ final class UserDefaultsDecodingTests {
     }
 
 }
+
+#endif // !os(Linux)
diff --git a/Tests/VexilTests/UserDefaultsEncodingTests.swift b/Tests/VexilTests/UserDefaultsEncodingTests.swift
index 8d736635..3088008c 100644
--- a/Tests/VexilTests/UserDefaultsEncodingTests.swift
+++ b/Tests/VexilTests/UserDefaultsEncodingTests.swift
@@ -11,6 +11,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+#if !os(Linux)
+
 import Foundation
 import Testing
 @testable import Vexil
@@ -244,3 +246,5 @@ final class UserDefaultsEncodingTests {
     }
 
 }
+
+#endif // !os(Linux)