diff --git a/mac-app/Sources/CloudMachineCore/SMBProbe.swift b/mac-app/Sources/CloudMachineCore/SMBProbe.swift
index fbdfd16..7191a16 100644
--- a/mac-app/Sources/CloudMachineCore/SMBProbe.swift
+++ b/mac-app/Sources/CloudMachineCore/SMBProbe.swift
@@ -135,7 +135,7 @@ public enum SMBProbe {
   }
 
   /// One connection: connect, send, read the first 8 bytes - all within `timeout`.
-  public static func liveExchange(
+  @Sendable public static func liveExchange(
     host: String, port: UInt16, request: [UInt8], timeout: TimeInterval
   ) -> Exchange {
     let deadline = Date().addingTimeInterval(timeout)
diff --git a/mac-app/Tests/CloudMachineAppTests/HealthAlertTests.swift b/mac-app/Tests/CloudMachineAppTests/HealthAlertTests.swift
index 48cb25b..e014dbf 100644
--- a/mac-app/Tests/CloudMachineAppTests/HealthAlertTests.swift
+++ b/mac-app/Tests/CloudMachineAppTests/HealthAlertTests.swift
@@ -49,8 +49,9 @@ final class HealthAlertTests: XCTestCase {
     _ report: BackupHealth.Report, now: Date = Date(),
     deliver: @escaping @Sendable (String, String) async -> Bool
   ) async -> Bool {
-    await HealthAlert.report(
-      report, now: now, stateFile: stateFile, deliver: deliver, log: log.write)
+    let captured = log!
+    return await HealthAlert.report(
+      report, now: now, stateFile: stateFile, deliver: deliver, log: { captured.write($0) })
   }
 
   // MARK: - Finding 3: tests do not write to the production log