diff --git a/Sources/YouTubeKit/Extensions/URLSessionDelegates.swift b/Sources/YouTubeKit/Extensions/URLSessionDelegates.swift
index 2cc1fcf..9e7183e 100644
--- a/Sources/YouTubeKit/Extensions/URLSessionDelegates.swift
+++ b/Sources/YouTubeKit/Extensions/URLSessionDelegates.swift
@@ -13,7 +13,11 @@ final class ConfigurableURLSessionDelegate: NSObject, URLSessionTaskDelegate {
     let applyCookiesOnRedirect: Bool
     let saveIntermediateResponses: Bool
     
+#if swift(>=5.10)
     nonisolated(unsafe) var intermediateResponses = [HTTPURLResponse]()
+#else
+    var intermediateResponses = [HTTPURLResponse]()
+#endif
     
     init(allowsRedirect: Bool, applyCookiesOnRedirect: Bool, saveIntermediateResponses: Bool) {
         self.allowsRedirects = allowsRedirect
diff --git a/Sources/YouTubeKit/YouTube.swift b/Sources/YouTubeKit/YouTube.swift
index 6f65de6..9f8e020 100644
--- a/Sources/YouTubeKit/YouTube.swift
+++ b/Sources/YouTubeKit/YouTube.swift
@@ -14,8 +14,13 @@ public class YouTube {
     private var _js: String?
     private var _jsURL: URL?
     
+#if swift(>=5.10)
     nonisolated(unsafe) private static var __js: String? // caches js between calls
     nonisolated(unsafe) private static var __jsURL: URL?
+#else
+    private static var __js: String? // caches js between calls
+    private static var __jsURL: URL?
+#endif
     
     private var _videoInfos: [InnerTube.VideoInfo]?