diff --git a/Sources/Diagnose/CMakeLists.txt b/Sources/Diagnose/CMakeLists.txt
index 4fc6aff33..cca945242 100644
--- a/Sources/Diagnose/CMakeLists.txt
+++ b/Sources/Diagnose/CMakeLists.txt
@@ -1,5 +1,4 @@
 add_library(Diagnose STATIC
-  CommandConfiguration+Sendable.swift
   CommandLineArgumentsReducer.swift
   DebugCommand.swift
   DiagnoseCommand.swift
diff --git a/Sources/Diagnose/CommandConfiguration+Sendable.swift b/Sources/Diagnose/CommandConfiguration+Sendable.swift
deleted file mode 100644
index 0504351e5..000000000
--- a/Sources/Diagnose/CommandConfiguration+Sendable.swift
+++ /dev/null
@@ -1,21 +0,0 @@
-//===----------------------------------------------------------------------===//
-//
-// This source file is part of the Swift.org open source project
-//
-// Copyright (c) 2014 - 2024 Apple Inc. and the Swift project authors
-// Licensed under Apache License v2.0 with Runtime Library Exception
-//
-// See https://swift.org/LICENSE.txt for license information
-// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
-//
-//===----------------------------------------------------------------------===//
-
-import ArgumentParser
-
-// If `CommandConfiguration` is not sendable, commands can't have static `configuration` properties.
-// Needed until we update Swift CI to swift-argument-parser 1.3.1, which has this conformance (rdar://128042447).
-#if compiler(<5.11)
-extension CommandConfiguration: @unchecked Sendable {}
-#else
-extension CommandConfiguration: @unchecked @retroactive Sendable {}
-#endif
diff --git a/Sources/SKTestSupport/RepeatUntilExpectedResult.swift b/Sources/SKTestSupport/RepeatUntilExpectedResult.swift
index a421645e4..ab25de52d 100644
--- a/Sources/SKTestSupport/RepeatUntilExpectedResult.swift
+++ b/Sources/SKTestSupport/RepeatUntilExpectedResult.swift
@@ -10,7 +10,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-import SKTestSupport
 import XCTest
 
 /// Runs the body repeatedly once per second until it returns `true`, giving up after `timeout`.
diff --git a/Sources/SKTestSupport/WrappedSemaphore.swift b/Sources/SKTestSupport/WrappedSemaphore.swift
index 52bad1b1e..c768d2bdd 100644
--- a/Sources/SKTestSupport/WrappedSemaphore.swift
+++ b/Sources/SKTestSupport/WrappedSemaphore.swift
@@ -11,7 +11,6 @@
 //===----------------------------------------------------------------------===//
 
 import Dispatch
-import SKTestSupport
 import XCTest
 
 /// Wrapper around `DispatchSemaphore` so that Swift Concurrency doesn't complain about the usage of semaphores in the
diff --git a/Sources/SourceKitD/DynamicallyLoadedSourceKitD.swift b/Sources/SourceKitD/DynamicallyLoadedSourceKitD.swift
index ab633b9a3..e68eed2b9 100644
--- a/Sources/SourceKitD/DynamicallyLoadedSourceKitD.swift
+++ b/Sources/SourceKitD/DynamicallyLoadedSourceKitD.swift
@@ -85,7 +85,7 @@ package actor DynamicallyLoadedSourceKitD: SourceKitD {
     self.api.shutdown()
     // FIXME: is it safe to dlclose() sourcekitd? If so, do that here. For now, let the handle leak.
     Task.detached(priority: .background) { [dylib] in
-      await dylib.leak()
+      dylib.leak()
     }
   }
 
diff --git a/Sources/SourceKitD/SourceKitD.swift b/Sources/SourceKitD/SourceKitD.swift
index 0f9dde69a..f7d2cb00f 100644
--- a/Sources/SourceKitD/SourceKitD.swift
+++ b/Sources/SourceKitD/SourceKitD.swift
@@ -15,11 +15,10 @@ import Dispatch
 import Foundation
 import SwiftExtensions
 
-#if compiler(>=6)
-extension sourcekitd_api_request_handle_t: @retroactive @unchecked Sendable {}
-#else
-extension sourcekitd_api_request_handle_t: @unchecked Sendable {}
-#endif
+fileprivate struct SourceKitDRequestHandle: Sendable {
+  /// `nonisolated(unsafe)` is fine because we just use the handle as an opaque value.
+  nonisolated(unsafe) let handle: sourcekitd_api_request_handle_t
+}
 
 /// Access to sourcekitd API, taking care of initialization, shutdown, and notification handler
 /// multiplexing.
@@ -107,16 +106,19 @@ extension SourceKitD {
     log(request: request)
 
     let sourcekitdResponse = try await withTimeout(timeout) {
-      return try await withCancellableCheckedThrowingContinuation { continuation in
+      return try await withCancellableCheckedThrowingContinuation { (continuation) -> SourceKitDRequestHandle? in
         var handle: sourcekitd_api_request_handle_t? = nil
         self.api.send_request(request.dict, &handle) { response in
           continuation.resume(returning: SKDResponse(response!, sourcekitd: self))
         }
-        return handle
-      } cancel: { handle in
+        if let handle {
+          return SourceKitDRequestHandle(handle: handle)
+        }
+        return nil
+      } cancel: { (handle: SourceKitDRequestHandle?) in
         if let handle {
           self.logRequestCancellation(request: request)
-          self.api.cancel_request(handle)
+          self.api.cancel_request(handle.handle)
         }
       }
     }
diff --git a/Sources/SourceKitLSP/Rename.swift b/Sources/SourceKitLSP/Rename.swift
index f15dd04b5..5600ce889 100644
--- a/Sources/SourceKitLSP/Rename.swift
+++ b/Sources/SourceKitLSP/Rename.swift
@@ -10,7 +10,7 @@
 //
 //===----------------------------------------------------------------------===//
 
-@preconcurrency import IndexStoreDB
+import IndexStoreDB
 import LanguageServerProtocol
 import SKLogging
 import SKSupport
diff --git a/Sources/SourceKitLSP/Swift/CodeActions/PackageManifestEdits.swift b/Sources/SourceKitLSP/Swift/CodeActions/PackageManifestEdits.swift
index 870ab95a1..b5e0b2106 100644
--- a/Sources/SourceKitLSP/Swift/CodeActions/PackageManifestEdits.swift
+++ b/Sources/SourceKitLSP/Swift/CodeActions/PackageManifestEdits.swift
@@ -35,7 +35,7 @@ struct PackageManifestEdits: SyntaxCodeActionProvider {
   ) -> [CodeAction] {
     do {
       var actions: [CodeAction] = []
-      let variants: [(TargetDescription.TargetType, String)] = [
+      let variants: [(TargetDescription.TargetKind, String)] = [
         (.regular, "library"),
         (.executable, "executable"),
         (.macro, "macro"),
diff --git a/Tests/SourceKitLSPTests/DocumentSymbolTests.swift b/Tests/SourceKitLSPTests/DocumentSymbolTests.swift
index a0420c15c..ec39e4bb9 100644
--- a/Tests/SourceKitLSPTests/DocumentSymbolTests.swift
+++ b/Tests/SourceKitLSPTests/DocumentSymbolTests.swift
@@ -762,7 +762,7 @@ final class DocumentSymbolTests: XCTestCase {
 fileprivate func assertDocumentSymbols(
   _ markedText: String,
   _ expectedDocumentSymbols: (DocumentPositions) -> [DocumentSymbol],
-  file: StaticString = #file,
+  file: StaticString = #filePath,
   line: UInt = #line
 ) async throws {
   let testClient = try await TestSourceKitLSPClient()
diff --git a/Tests/SourceKitLSPTests/FoldingRangeTests.swift b/Tests/SourceKitLSPTests/FoldingRangeTests.swift
index c594ffdd6..ff89a85f8 100644
--- a/Tests/SourceKitLSPTests/FoldingRangeTests.swift
+++ b/Tests/SourceKitLSPTests/FoldingRangeTests.swift
@@ -44,7 +44,7 @@ func assertFoldingRanges(
   expectedRanges: [FoldingRangeSpec],
   rangeLimit: Int? = nil,
   lineFoldingOnly: Bool = false,
-  file: StaticString = #file,
+  file: StaticString = #filePath,
   line: UInt = #line
 ) async throws {
   let capabilities = ClientCapabilities(
diff --git a/Tests/SourceKitLSPTests/HoverTests.swift b/Tests/SourceKitLSPTests/HoverTests.swift
index 02376ad08..0936b4369 100644
--- a/Tests/SourceKitLSPTests/HoverTests.swift
+++ b/Tests/SourceKitLSPTests/HoverTests.swift
@@ -176,7 +176,7 @@ final class HoverTests: XCTestCase {
 private func assertHover(
   _ markedSource: String,
   expectedContent: String,
-  file: StaticString = #file,
+  file: StaticString = #filePath,
   line: UInt = #line
 ) async throws {
   let testClient = try await TestSourceKitLSPClient()
diff --git a/Tests/SourceKitLSPTests/RenameAssertions.swift b/Tests/SourceKitLSPTests/RenameAssertions.swift
index 0c476aa4e..209f0f02a 100644
--- a/Tests/SourceKitLSPTests/RenameAssertions.swift
+++ b/Tests/SourceKitLSPTests/RenameAssertions.swift
@@ -39,7 +39,7 @@ func assertSingleFileRename(
   expectedPrepareRenamePlaceholder: String,
   expected: String,
   testName: String = #function,
-  file: StaticString = #file,
+  file: StaticString = #filePath,
   line: UInt = #line
 ) async throws {
   try await SkipUnless.sourcekitdSupportsRename()
@@ -99,7 +99,7 @@ func assertRenamedSourceMatches(
   in ws: MultiFileTestProject,
   message: String,
   testName: String = #function,
-  file: StaticString = #file,
+  file: StaticString = #filePath,
   line: UInt = #line
 ) throws {
   for (expectedFileLocation, expectedRenamed) in expected {
@@ -138,7 +138,7 @@ func assertMultiFileRename(
   manifest: String = SwiftPMTestProject.defaultPackageManifest,
   preRenameActions: (SwiftPMTestProject) throws -> Void = { _ in },
   testName: String = #function,
-  file: StaticString = #file,
+  file: StaticString = #filePath,
   line: UInt = #line
 ) async throws {
   try await SkipUnless.sourcekitdSupportsRename()
diff --git a/Tests/SourceKitLSPTests/TypeHierarchyTests.swift b/Tests/SourceKitLSPTests/TypeHierarchyTests.swift
index a7ac1242f..1b9433a9e 100644
--- a/Tests/SourceKitLSPTests/TypeHierarchyTests.swift
+++ b/Tests/SourceKitLSPTests/TypeHierarchyTests.swift
@@ -225,7 +225,7 @@ fileprivate extension TypeHierarchyItem {
 fileprivate func assertEqualIgnoringData(
   _ actual: [TypeHierarchyItem]?,
   _ expected: [TypeHierarchyItem],
-  file: StaticString = #file,
+  file: StaticString = #filePath,
   line: UInt = #line
 ) {
   guard let actual else {