diff --git a/Tests/Resources/SwiftTestMain.swift b/Tests/Resources/SwiftTestMain.swift
index 784d4c19b9c..3b18cc55541 100644
--- a/Tests/Resources/SwiftTestMain.swift
+++ b/Tests/Resources/SwiftTestMain.swift
@@ -13,7 +13,7 @@ func swt_abiv0_getEntryPoint() -> UnsafeRawPointer
 
 @main struct Runner {
     static func main() async throws {
-        let configurationJSON: UnsafeRawBufferPointer? = nil
+        nonisolated(unsafe) let configurationJSON: UnsafeRawBufferPointer? = nil
         let recordHandler: @Sendable (UnsafeRawBufferPointer) -> Void = { _ in }
 
         let entryPoint = unsafeBitCast(swt_abiv0_getEntryPoint(), to: EntryPoint.self)