diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 9d3a6e27..24b143a3 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -21,7 +21,7 @@ jobs:
       matrix:
         command: [test, ""]
         platform: [IOS, MAC_CATALYST, MACOS, TVOS, VISIONOS, WATCHOS]
-        xcode: [15.4, "16.0"]
+        xcode: ["15.4", "16.0"]
         exclude:
           - { platform: VISIONOS }
         include:
diff --git a/Makefile b/Makefile
index 4961c1b4..7d9f5b66 100644
--- a/Makefile
+++ b/Makefile
@@ -81,6 +81,22 @@ test-docs:
 format:
 	@swift format -i -r --ignore-unparsable-files .
 
+
+test-linux:
+	docker run \
+		--rm \
+		-v "$(PWD):$(PWD)" \
+		-w "$(PWD)" \
+		swift:5.10 \
+		bash -c 'swift test -c $(CONFIG)'
+
+build-linux:
+	docker run \
+		--rm \
+		-v "$(PWD):$(PWD)" \
+		-w "$(PWD)" \
+		swift:5.9 \
+		bash -c 'swift build -c $(CONFIG)'
 .PHONY: build-for-library-evolution format xcodebuild test-docs test-integration
 
 define udid_for
diff --git a/Sources/Auth/AuthClient.swift b/Sources/Auth/AuthClient.swift
index 854a7c4b..1cec6346 100644
--- a/Sources/Auth/AuthClient.swift
+++ b/Sources/Auth/AuthClient.swift
@@ -21,7 +21,9 @@ public final class AuthClient: Sendable {
 
   private var api: APIClient { Dependencies[clientID].api }
   var configuration: AuthClient.Configuration { Dependencies[clientID].configuration }
-  private var codeVerifierStorage: CodeVerifierStorage { Dependencies[clientID].codeVerifierStorage }
+  private var codeVerifierStorage: CodeVerifierStorage {
+    Dependencies[clientID].codeVerifierStorage
+  }
   private var date: @Sendable () -> Date { Dependencies[clientID].date }
   private var sessionManager: SessionManager { Dependencies[clientID].sessionManager }
   private var eventEmitter: AuthStateChangeEventEmitter { Dependencies[clientID].eventEmitter }
@@ -77,10 +79,11 @@ public final class AuthClient: Sendable {
       sessionManager: .live(clientID: clientID)
     )
 
-    observeAppLifecycleChanges()
+    Task { @MainActor in observeAppLifecycleChanges() }
   }
 
   #if canImport(ObjectiveC)
+    @MainActor
     private func observeAppLifecycleChanges() {
       #if canImport(UIKit)
         #if canImport(WatchKit)
@@ -165,14 +168,20 @@ public final class AuthClient: Sendable {
   /// Listen for auth state changes.
   ///
   /// An `.initialSession` is always emitted when this method is called.
-  public var authStateChanges: AsyncStream<(
-    event: AuthChangeEvent,
-    session: Session?
-  )> {
-    let (stream, continuation) = AsyncStream<(
-      event: AuthChangeEvent,
-      session: Session?
-    )>.makeStream()
+  public var authStateChanges:
+    AsyncStream<
+      (
+        event: AuthChangeEvent,
+        session: Session?
+      )
+    >
+  {
+    let (stream, continuation) = AsyncStream<
+      (
+        event: AuthChangeEvent,
+        session: Session?
+      )
+    >.makeStream()
 
     Task {
       let handle = await onAuthStateChange { event, session in
@@ -209,10 +218,12 @@ public final class AuthClient: Sendable {
         url: configuration.url.appendingPathComponent("signup"),
         method: .post,
         query: [
-          (redirectTo ?? configuration.redirectToURL).map { URLQueryItem(
-            name: "redirect_to",
-            value: $0.absoluteString
-          ) },
+          (redirectTo ?? configuration.redirectToURL).map {
+            URLQueryItem(
+              name: "redirect_to",
+              value: $0.absoluteString
+            )
+          }
         ].compactMap { $0 },
         body: configuration.encoder.encode(
           SignUpRequest(
@@ -401,10 +412,12 @@ public final class AuthClient: Sendable {
         url: configuration.url.appendingPathComponent("otp"),
         method: .post,
         query: [
-          (redirectTo ?? configuration.redirectToURL).map { URLQueryItem(
-            name: "redirect_to",
-            value: $0.absoluteString
-          ) },
+          (redirectTo ?? configuration.redirectToURL).map {
+            URLQueryItem(
+              name: "redirect_to",
+              value: $0.absoluteString
+            )
+          }
         ].compactMap { $0 },
         body: configuration.encoder.encode(
           OTPParams(
@@ -524,7 +537,8 @@ public final class AuthClient: Sendable {
     let codeVerifier = codeVerifierStorage.get()
 
     if codeVerifier == nil {
-      logger?.error("code verifier not found, a code verifier should exist when calling this method.")
+      logger?.error(
+        "code verifier not found, a code verifier should exist when calling this method.")
     }
 
     let session: Session = try await api.execute(
@@ -878,7 +892,9 @@ public final class AuthClient: Sendable {
           headers: [.authorization: "Bearer \(accessToken)"]
         )
       )
-    } catch let AuthError.api(_, _, _, response) where [404, 403, 401].contains(response.statusCode) {
+    } catch let AuthError.api(_, _, _, response)
+      where [404, 403, 401].contains(response.statusCode)
+    {
       // ignore 404s since user might not exist anymore
       // ignore 401s, and 403s since an invalid or expired JWT should sign out the current session.
     }
@@ -898,10 +914,12 @@ public final class AuthClient: Sendable {
         url: configuration.url.appendingPathComponent("verify"),
         method: .post,
         query: [
-          (redirectTo ?? configuration.redirectToURL).map { URLQueryItem(
-            name: "redirect_to",
-            value: $0.absoluteString
-          ) },
+          (redirectTo ?? configuration.redirectToURL).map {
+            URLQueryItem(
+              name: "redirect_to",
+              value: $0.absoluteString
+            )
+          }
         ].compactMap { $0 },
         body: configuration.encoder.encode(
           VerifyOTPParams.email(
@@ -991,10 +1009,12 @@ public final class AuthClient: Sendable {
         url: configuration.url.appendingPathComponent("resend"),
         method: .post,
         query: [
-          (emailRedirectTo ?? configuration.redirectToURL).map { URLQueryItem(
-            name: "redirect_to",
-            value: $0.absoluteString
-          ) },
+          (emailRedirectTo ?? configuration.redirectToURL).map {
+            URLQueryItem(
+              name: "redirect_to",
+              value: $0.absoluteString
+            )
+          }
         ].compactMap { $0 },
         body: configuration.encoder.encode(
           ResendEmailParams(
@@ -1078,10 +1098,12 @@ public final class AuthClient: Sendable {
         url: configuration.url.appendingPathComponent("user"),
         method: .put,
         query: [
-          (redirectTo ?? configuration.redirectToURL).map { URLQueryItem(
-            name: "redirect_to",
-            value: $0.absoluteString
-          ) },
+          (redirectTo ?? configuration.redirectToURL).map {
+            URLQueryItem(
+              name: "redirect_to",
+              value: $0.absoluteString
+            )
+          }
         ].compactMap { $0 },
         body: configuration.encoder.encode(user)
       )
@@ -1213,10 +1235,12 @@ public final class AuthClient: Sendable {
         url: configuration.url.appendingPathComponent("recover"),
         method: .post,
         query: [
-          (redirectTo ?? configuration.redirectToURL).map { URLQueryItem(
-            name: "redirect_to",
-            value: $0.absoluteString
-          ) },
+          (redirectTo ?? configuration.redirectToURL).map {
+            URLQueryItem(
+              name: "redirect_to",
+              value: $0.absoluteString
+            )
+          }
         ].compactMap { $0 },
         body: configuration.encoder.encode(
           RecoverParams(
@@ -1300,7 +1324,7 @@ public final class AuthClient: Sendable {
     }
 
     var queryItems: [URLQueryItem] = [
-      URLQueryItem(name: "provider", value: provider.rawValue),
+      URLQueryItem(name: "provider", value: provider.rawValue)
     ]
 
     if let scopes {
diff --git a/Sources/Storage/StorageFileApi.swift b/Sources/Storage/StorageFileApi.swift
index f98c31b8..42613097 100644
--- a/Sources/Storage/StorageFileApi.swift
+++ b/Sources/Storage/StorageFileApi.swift
@@ -51,13 +51,8 @@ enum FileUpload {
 }
 
 #if DEBUG
-  #if compiler(>=6)
-    // It is safe to mark it as unsafe, since this property is only used in tests for overriding the
-    // boundary value, instead of using the random one.
-    nonisolated(unsafe) var testingBoundary: String?
-  #else
-    var testingBoundary: String?
-  #endif
+  import ConcurrencyExtras
+  let testingBoundary = LockIsolated<String?>(nil)
 #endif
 
 /// Supabase Storage File API
@@ -94,7 +89,7 @@ public class StorageFileApi: StorageApi, @unchecked Sendable {
     headers[.duplex] = options.duplex
 
     #if DEBUG
-      let formData = MultipartFormData(boundary: testingBoundary)
+      let formData = MultipartFormData(boundary: testingBoundary.value)
     #else
       let formData = MultipartFormData()
     #endif
diff --git a/Tests/StorageTests/SupabaseStorageTests.swift b/Tests/StorageTests/SupabaseStorageTests.swift
index 1f36c366..5742538d 100644
--- a/Tests/StorageTests/SupabaseStorageTests.swift
+++ b/Tests/StorageTests/SupabaseStorageTests.swift
@@ -94,7 +94,7 @@ final class SupabaseStorageTests: XCTestCase {
 
   #if !os(Linux)
     func testUploadData() async throws {
-      testingBoundary = "alamofire.boundary.c21f947c1c7b0c57"
+      testingBoundary.setValue("alamofire.boundary.c21f947c1c7b0c57")
 
       sessionMock.fetch = { request in
         assertInlineSnapshot(of: request, as: .curl) {
@@ -155,7 +155,7 @@ final class SupabaseStorageTests: XCTestCase {
     }
 
     func testUploadFileURL() async throws {
-      testingBoundary = "alamofire.boundary.c21f947c1c7b0c57"
+      testingBoundary.setValue("alamofire.boundary.c21f947c1c7b0c57")
 
       sessionMock.fetch = { request in
         assertInlineSnapshot(of: request, as: .curl) {