diff --git a/Sources/SWBBuildService/Messages.swift b/Sources/SWBBuildService/Messages.swift
index 070b5d3c..ded6b880 100644
--- a/Sources/SWBBuildService/Messages.swift
+++ b/Sources/SWBBuildService/Messages.swift
@@ -99,12 +99,10 @@ private struct MacCatalystUnavailableFrameworkNamesHandler: MessageHandler {
     }
 }
 
+// TODO: Delete once all clients are no longer calling the public APIs which invoke this message
 private struct AppleSystemFrameworkNamesHandler: MessageHandler {
     func handle(request: Request, message: AppleSystemFrameworkNamesRequest) async throws -> StringListResponse {
-        guard let buildService = request.service as? BuildService else {
-            throw StubError.error("service object is not of type BuildService")
-        }
-        return try await StringListResponse([])
+        return StringListResponse([])
     }
 }
 
diff --git a/Sources/SWBCore/LibSwiftDriver/PlannedBuild.swift b/Sources/SWBCore/LibSwiftDriver/PlannedBuild.swift
index 5b7a5685..8fcefc65 100644
--- a/Sources/SWBCore/LibSwiftDriver/PlannedBuild.swift
+++ b/Sources/SWBCore/LibSwiftDriver/PlannedBuild.swift
@@ -25,7 +25,7 @@ private extension Path {
     init(_ virtualPath: TypedVirtualPath) throws {
         switch virtualPath.file {
         case let .absolute(absPath): self = Path(absPath.pathString)
-        case .standardInput, .standardOutput, .fileList, .relative, .temporary, .temporaryWithKnownContents:
+        case .standardInput, .standardOutput, .fileList, .relative, .temporary, .temporaryWithKnownContents, .buildArtifactWithKnownContents:
             fallthrough
         @unknown default:
             throw StubError.error("Cannot build Path from \(virtualPath); unimplemented path type.")
diff --git a/Sources/SWBCore/LinkageDependencyResolver.swift b/Sources/SWBCore/LinkageDependencyResolver.swift
index 9c648201..78897d9d 100644
--- a/Sources/SWBCore/LinkageDependencyResolver.swift
+++ b/Sources/SWBCore/LinkageDependencyResolver.swift
@@ -166,7 +166,7 @@ actor LinkageDependencyResolver {
                 return nil
             }
             let buildParameters = resolver.buildParametersByTarget[target] ?? configuredTarget.parameters
-            if await !resolver.isTargetSuitableForPlatformForIndex(target, parameters: buildParameters, imposedParameters: imposedParameters) {
+            if !resolver.isTargetSuitableForPlatformForIndex(target, parameters: buildParameters, imposedParameters: imposedParameters) {
                 return nil
             }
             let effectiveImposedParameters = imposedParameters?.effectiveParameters(target: configuredTarget, dependency: ConfiguredTarget(parameters: buildParameters, target: target), dependencyResolver: resolver)
diff --git a/Sources/SWBCore/SpecImplementations/Tools/CCompiler.swift b/Sources/SWBCore/SpecImplementations/Tools/CCompiler.swift
index d09d9119..279b0b3b 100644
--- a/Sources/SWBCore/SpecImplementations/Tools/CCompiler.swift
+++ b/Sources/SWBCore/SpecImplementations/Tools/CCompiler.swift
@@ -1065,7 +1065,7 @@ public class ClangCompilerSpec : CompilerSpec, SpecIdentifierType, GCCCompatible
 
         // Start with the executable.
         let compilerExecPath = resolveExecutablePath(cbc, forLanguageOfFileType: resolvedInputFileType)
-        let launcher = await resolveCompilerLauncher(cbc, compilerPath: compilerExecPath, delegate: delegate)
+        let launcher = resolveCompilerLauncher(cbc, compilerPath: compilerExecPath, delegate: delegate)
         if let launcher {
             commandLine += [launcher.str]
         }
diff --git a/Sources/SWBTestSupport/Timeout.swift b/Sources/SWBTestSupport/Timeout.swift
index 42e54606..c50176b5 100644
--- a/Sources/SWBTestSupport/Timeout.swift
+++ b/Sources/SWBTestSupport/Timeout.swift
@@ -14,7 +14,7 @@ package struct TimeoutError: Error {
     package var description: String?
 }
 
-package func withTimeout<T: Sendable>(
+@discardableResult package func withTimeout<T: Sendable>(
     timeout: Duration,
     description: String? = nil,
     block: sending () async throws -> T
diff --git a/Tests/SWBBuildSystemTests/CustomTaskBuildOperationTests.swift b/Tests/SWBBuildSystemTests/CustomTaskBuildOperationTests.swift
index 763d508a..736b48d2 100644
--- a/Tests/SWBBuildSystemTests/CustomTaskBuildOperationTests.swift
+++ b/Tests/SWBBuildSystemTests/CustomTaskBuildOperationTests.swift
@@ -29,7 +29,6 @@ fileprivate struct CustomTaskBuildOperationTests: CoreBasedTests {
         try await withTemporaryDirectory { tmpDir in
             let destination: RunDestinationInfo = .host
             let core = try await getCore()
-            let toolchain = try #require(core.toolchainRegistry.defaultToolchain)
             let environment = destination.hostRuntimeEnvironment(core)
 
             let testProject = TestProject(
diff --git a/Tests/SWBCoreTests/DependencyScopingTests.swift b/Tests/SWBCoreTests/DependencyScopingTests.swift
index 635577d9..a18490c4 100644
--- a/Tests/SWBCoreTests/DependencyScopingTests.swift
+++ b/Tests/SWBCoreTests/DependencyScopingTests.swift
@@ -160,7 +160,6 @@ import Foundation
         // Configure the targets and create a BuildRequest.
         let buildParameters = BuildParameters(configuration: "Debug")
         let t1 = BuildRequest.BuildTargetInfo(parameters: buildParameters, target: try #require(workspace.target(named: "T1")))
-        let t2 = BuildRequest.BuildTargetInfo(parameters: buildParameters, target: try #require(workspace.target(named: "T2")))
         do {
             let buildRequest = BuildRequest(parameters: buildParameters, buildTargets: [t1], dependencyScope: .workspace, continueBuildingAfterErrors: true, useParallelTargets: false, useImplicitDependencies: true, useDryRun: false)
             let buildRequestContext = BuildRequestContext(workspaceContext: workspaceContext)
diff --git a/Tests/SWBUtilPerfTests/MsgPackSerializationPerfTests.swift b/Tests/SWBUtilPerfTests/MsgPackSerializationPerfTests.swift
index 5727c39e..dd005c7e 100644
--- a/Tests/SWBUtilPerfTests/MsgPackSerializationPerfTests.swift
+++ b/Tests/SWBUtilPerfTests/MsgPackSerializationPerfTests.swift
@@ -44,7 +44,7 @@ fileprivate struct MsgPackSerializationPerfTests: PerfTests {
         await measure {
             for _ in 1...iterations
             {
-                #expect(self.serializeScalarData() != nil)
+                #expect(!self.serializeScalarData().byteString.isEmpty)
             }
         }
     }
@@ -91,7 +91,7 @@ fileprivate struct MsgPackSerializationPerfTests: PerfTests {
 
         await measure {
             for _ in 1...iterations {
-                #expect(self.serializeStringData() != nil)
+                #expect(!self.serializeStringData().byteString.isEmpty)
             }
         }
     }
@@ -133,7 +133,7 @@ fileprivate struct MsgPackSerializationPerfTests: PerfTests {
         await measure {
             for _ in 1...iterations
             {
-                #expect(self.serializeArrayData() != nil)
+                #expect(!self.serializeArrayData().byteString.isEmpty)
             }
         }
     }
@@ -171,7 +171,7 @@ fileprivate struct MsgPackSerializationPerfTests: PerfTests {
 
         await measure {
             for _ in 1...iterations {
-                #expect(self.serializeDictionaryData() != nil)
+                #expect(!self.serializeDictionaryData().byteString.isEmpty)
             }
         }
     }
@@ -220,7 +220,7 @@ fileprivate struct MsgPackSerializationPerfTests: PerfTests {
         {
             for _ in 1...iterations
             {
-                #expect(self.serializeCustomElementData(elements) != nil)
+                #expect(!self.serializeCustomElementData(elements).byteString.isEmpty)
             }
         }
     }
diff --git a/Tests/SWBUtilTests/FSProxyTests.swift b/Tests/SWBUtilTests/FSProxyTests.swift
index 0389b852..ebfced2a 100644
--- a/Tests/SWBUtilTests/FSProxyTests.swift
+++ b/Tests/SWBUtilTests/FSProxyTests.swift
@@ -466,8 +466,6 @@ import SWBTestSupport
             let fileAtts = try FileManager.default.attributesOfItem(atPath: filePath.str)
             let fileMgrModDate = try #require(fileAtts[FileAttributeKey.modificationDate] as? Date)
 
-            // not working on Windows for some reason
-            let hostOS = try ProcessInfo.processInfo.hostOperatingSystem()
             #expect(fsModDate == fileMgrModDate)
         }
     }