diff --git a/src/mono/wasm/Wasm.Build.Tests/Common/BuildEnvironment.cs b/src/mono/wasm/Wasm.Build.Tests/Common/BuildEnvironment.cs
index 37a7668b5d099a..facc67c730147f 100644
--- a/src/mono/wasm/Wasm.Build.Tests/Common/BuildEnvironment.cs
+++ b/src/mono/wasm/Wasm.Build.Tests/Common/BuildEnvironment.cs
@@ -37,7 +37,7 @@ public class BuildEnvironment
         public static readonly string           RelativeTestAssetsPath = @"..\testassets\";
         public static readonly string           TestAssetsPath = Path.Combine(AppContext.BaseDirectory, "testassets");
         public static readonly string           TestDataPath = Path.Combine(AppContext.BaseDirectory, "data");
-        public static readonly string           TmpPath = Path.Combine(AppContext.BaseDirectory, "wbt");
+        public static readonly string           TmpPath = Path.Combine(AppContext.BaseDirectory, "wbt artifacts");
 
         public static readonly string           DefaultRuntimeIdentifier =
 #if TARGET_WASI
diff --git a/src/mono/wasm/build/WasmApp.Native.targets b/src/mono/wasm/build/WasmApp.Native.targets
index d9595b16c2eb42..49b1ad7cb4a3c9 100644
--- a/src/mono/wasm/build/WasmApp.Native.targets
+++ b/src/mono/wasm/build/WasmApp.Native.targets
@@ -3,7 +3,7 @@
 
   <UsingTask TaskName="Microsoft.WebAssembly.Build.Tasks.ManagedToNativeGenerator" AssemblyFile="$(WasmAppBuilderTasksAssemblyPath)" />
   <UsingTask TaskName="Microsoft.WebAssembly.Build.Tasks.EmccCompile" AssemblyFile="$(WasmAppBuilderTasksAssemblyPath)" />
-  <UsingTask TaskName="MonoTargetsTasks.MarshalingPInvokeScanner" AssemblyFile="$(MonoTargetsTasksAssemblyPath)" />
+  <UsingTask TaskName="MonoTargetsTasks.MarshalingPInvokeScanner" AssemblyFile="$(MonoTargetsTasksAssemblyPath)" /> 
 
   <PropertyGroup>
     <_WasmBuildNativeCoreDependsOn>
@@ -211,7 +211,7 @@
 
       <_EmccCompileBitcodeRsp>$(_WasmIntermediateOutputPath)emcc-compile-bc.rsp</_EmccCompileBitcodeRsp>
       <_EmccLinkRsp>$(_WasmIntermediateOutputPath)emcc-link.rsp</_EmccLinkRsp>
-
+      
       <EmccInitialHeapSize Condition="'$(EmccInitialHeapSize)' == ''">$(EmccTotalMemory)</EmccInitialHeapSize>
       <EmccStackSize Condition="'$(EmccStackSize)' == ''">5MB</EmccStackSize>
       <WasmAllowUndefinedSymbols Condition="'$(WasmAllowUndefinedSymbols)' == ''">false</WasmAllowUndefinedSymbols>
@@ -250,7 +250,7 @@
       <_EmccCFlags Include="-DGEN_PINVOKE=1" />
       <_EmccCFlags Include="-emit-llvm" />
 
-      <_EmccCFlags Include="&quot;-I%(_EmccIncludePaths.Identity)&quot;" />
+      <_EmccCFlags Include="-I&quot;%(_EmccIncludePaths.Identity)&quot;" />
 
       <!-- Adding optimization flag at the top, so it gets precedence -->
       <_EmccLDFlags Include="$(EmccLinkOptimizationFlag)" />
diff --git a/src/mono/wasm/build/WasmApp.targets b/src/mono/wasm/build/WasmApp.targets
index b4040156dfeab6..cd2cf82ba6cc65 100644
--- a/src/mono/wasm/build/WasmApp.targets
+++ b/src/mono/wasm/build/WasmApp.targets
@@ -490,7 +490,7 @@
       <FileWrites Include="$(WasmRunV8ScriptPath)" />
     </ItemGroup>
 
-    <Exec Condition="'$(OS)' != 'Windows_NT'" Command="chmod a+x $(WasmRunV8ScriptPath)" />
+    <Exec Condition="'$(OS)' != 'Windows_NT'" Command="chmod a+x '$(WasmRunV8ScriptPath)'" />
   </Target>
 
   <Target Name="_WasmResolveReferences" Condition="'$(WasmResolveAssembliesBeforeBuild)' == 'true'">
diff --git a/src/tasks/AotCompilerTask/MonoAOTCompiler.cs b/src/tasks/AotCompilerTask/MonoAOTCompiler.cs
index 9e52322770b04a..7d22da51109fa3 100644
--- a/src/tasks/AotCompilerTask/MonoAOTCompiler.cs
+++ b/src/tasks/AotCompilerTask/MonoAOTCompiler.cs
@@ -951,7 +951,7 @@ private PrecompileArguments GetPrecompileArgumentsFor(ITaskItem assemblyItem, st
         if (isDedup)
         {
             foreach (var aItem in _assembliesToCompile!)
-                processArgs.Add(aItem.ItemSpec);
+                processArgs.Add('"' + aItem.ItemSpec + '"');
         }
         else
         {
diff --git a/src/tasks/WasmAppBuilder/CreateResponseFile.cs b/src/tasks/WasmAppBuilder/CreateResponseFile.cs
new file mode 100644
index 00000000000000..c3206b91496294
--- /dev/null
+++ b/src/tasks/WasmAppBuilder/CreateResponseFile.cs
@@ -0,0 +1,99 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System;
+using System.Collections.Concurrent;
+using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.Build.Framework;
+using Microsoft.Build.Utilities;
+
+namespace Microsoft.WebAssembly.Build.Tasks
+{
+    /// <summary>
+    /// This cannot be done with WriteLinesToFile task because we need to parse EmccCFlags before saving to file
+    /// by escaping spaces with backslashes. MsBuild converts all backslashes to forward slashes automatically,
+    /// so it cannot be done directly in the .targets (https://github.com/dotnet/msbuild/issues/3468).
+    /// </summary>
+    public class CreateResponseFile : Microsoft.Build.Utilities.Task
+    {
+        [NotNull]
+        [Required]
+        public ITaskItem[]? EmccCFlags            { get; set; }
+        [Required]
+        public string?      FilePath              { get; set; }
+        public bool         Overwrite             { get; set; } = true;
+        public bool         WriteOnlyWhenDifferent{ get; set; } = true;
+        public override bool Execute()
+        {
+            try
+            {
+                return ExecuteActual();
+            }
+            catch (LogAsErrorException laee)
+            {
+                Log.LogError(laee.Message);
+                return false;
+            }
+        }
+
+        private bool ExecuteActual()
+        {
+            if (EmccCFlags.Length == 0)
+            {
+                Log.LogError($"No Emcc flags to write");
+                return false;
+            }
+
+            if (string.IsNullOrEmpty(FilePath))
+            {
+                Log.LogError($"FilePath is empty");
+                return false;
+            }
+
+            if (File.Exists(FilePath))
+            {
+                if (!Overwrite)
+                    return true;
+                var lines = File.ReadLines(FilePath);
+                bool isDifferent = lines.Count() != EmccCFlags.Length;
+                if (!isDifferent)
+                {
+                    foreach (var element in lines.Zip(EmccCFlags, (line, flag) => new { Line = line, Flag = flag }) )
+                    {
+                        if (element.Line != element.Flag.ItemSpec)
+                        {
+                            Log.LogMessage($"Has a different line, element.Line={element.Line}, element.Flag.ItemSpec={element.Flag.ItemSpec}");
+                            isDifferent = true;
+                            break;
+                        }
+                    }
+                }
+                if (WriteOnlyWhenDifferent && isDifferent)
+                    return true;
+                Write(FilePath, EmccCFlags);
+            }
+            else
+            {
+                Write(FilePath, EmccCFlags);
+            }
+            return !Log.HasLoggedErrors;
+        }
+
+        private static void Write(string path, ITaskItem[] flags)
+        {
+            using (StreamWriter outputFile = new StreamWriter(path))
+            {
+                foreach (ITaskItem flag in flags)
+                {
+                    outputFile.WriteLine(flag.ItemSpec.Replace(" ", "\\ "));
+                }
+            }
+        }
+    }
+}