Add RnwNewArch property and RNW_NEW_ARCH constants when building projects for the new architecture

.ado/jobs/cli-init-windows.yml

@@ -325,12 +325,6 @@ jobs:
                   platform: ${{ parameters.platform }}
                   configuration: ${{ parameters.configuration }}
                   buildEnvironment: ${{ parameters.buildEnvironment }}
-
-              - task: CmdLine@2
-                displayName: Create npm directory
-                name: createNpmDirectory
-                inputs:
-                  script: mkdir %APPDATA%\npm
 
               - template: ../templates/react-native-init-windows.yml
                 parameters:

.ado/jobs/playground.yml

@@ -180,6 +180,8 @@ jobs:
                   msbuildArgs:
                     /p:PackageCertificateKeyFile=$(Build.SourcesDirectory)\EncodedKey.pfx
                     /p:PackageCertificatePassword=${{ parameters.certificatePassword }}
+                ${{if eq(matrix.SolutionFile, 'Playground-Composition.sln')}}:
+                  parallelBuild: false # required to workaround issue #13599
 
             - ${{if and(false, endsWith(matrix.Name, 'Universal'), eq(matrix.BuildConfiguration, 'Debug')) }}: # Disabled as debugging doesn't work,remove false after issue is resolved, see https://github.com/microsoft/react-native-windows/issues/13543
               # Execute debug feature tests (skip this step for the Win32 Playground app and for release builds)

.ado/publish.yml

@@ -190,9 +190,6 @@ extends:
 
           - template: .ado/templates/run-compliance-prebuild.yml@self
 
-          - script: if not exist %USERPROFILE%\AppData\Roaming\npm (mkdir %USERPROFILE%\AppData\Roaming\npm)
-            displayName: Fix missing npm config
-
           - pwsh: |
               npx beachball check --verbose 2>&1 | Tee-Object -Variable beachballOutput
               $beachballErrors = $beachballOutput | Where-Object { $_ -match "ERROR: *"}

.ado/templates/enable-fabric-experimental-feature.yml

@@ -5,7 +5,7 @@ steps:
       $nsm.AddNamespace('ns', $experimentalFeatures.DocumentElement.NamespaceURI)
 
       $xmlNode = $experimentalFeatures.CreateElement("PropertyGroup");
-      $xmlNode.InnerXml = "<UseFabric>true</UseFabric><UseWinUI3>true</UseWinUI3>"
+      $xmlNode.InnerXml = "<RnwNewArch>true</RnwNewArch><UseFabric>true</UseFabric><UseWinUI3>true</UseWinUI3>"
 
       $experimentalFeatures.DocumentElement.AppendChild($xmlNode);
 

.ado/templates/msbuild-sln.yml

@@ -15,6 +15,7 @@ parameters:
   msbuildArguments: ''
   warnAsError: true
   oneESMode: false
+  parallelBuild: true
 
 steps:
   - powershell: |
@@ -36,7 +37,7 @@ steps:
       platform: ${{ parameters.buildPlatform }}
       configuration: ${{ parameters.buildConfiguration }}
       clean: false # Optional
-      maximumCpuCount: true
+      maximumCpuCount: ${{parameters.parallelBuild}}
       restoreNugetPackages: false # Optional
       createLogFile: true
       logFileVerbosity: detailed

.ado/templates/prepare-js-env.yml

@@ -13,6 +13,10 @@ steps:
       inputs:
         versionSpec: '18.x'
 
+  - script: if not exist %APPDATA%\npm (mkdir %APPDATA%\npm)
+    displayName: Ensure npm directory for npx commands
+    condition: eq(variables['Agent.OS'], 'Windows_NT')
+
   - template: yarn-install.yml
     parameters:
       agentImage: ${{ parameters.agentImage }}

change/@react-native-windows-automation-channel-4c7447b5-805b-4261-a652-820c2d3ed0cc.json

@@ -0,0 +1,7 @@
+{
+  "type": "patch",
+  "comment": "Add RnwNewArch property and RNW_NEW_ARCH constants when building projects for the new architecture",
+  "packageName": "@react-native-windows/automation-channel",
+  "email": "[email protected]",
+  "dependentChangeType": "patch"
+}

change/@react-native-windows-codegen-386a49a7-d732-4d58-b692-37841cecd8b9.json

@@ -0,0 +1,7 @@
+{
+  "type": "prerelease",
+  "comment": "Add RnwNewArch property and RNW_NEW_ARCH constants when building projects for the new architecture",
+  "packageName": "@react-native-windows/codegen",
+  "email": "[email protected]",
+  "dependentChangeType": "patch"
+}

change/react-native-windows-44e5d751-697d-41eb-806c-037f525ef1de.json

@@ -0,0 +1,7 @@
+{
+  "type": "prerelease",
+  "comment": "Add RnwNewArch property and RNW_NEW_ARCH constants when building projects for the new architecture",
+  "packageName": "react-native-windows",
+  "email": "[email protected]",
+  "dependentChangeType": "patch"
+}

packages/@react-native-windows/automation-channel/package.json

@@ -22,6 +22,7 @@
     "jsonrpc-lite": "^2.2.0"
   },
   "devDependencies": {
+    "@react-native-community/cli": "15.0.0-alpha.2",
     "@rnw-scripts/eslint-config": "1.2.30",
     "@rnw-scripts/just-task": "2.3.47",
     "@rnw-scripts/ts-config": "2.0.5",
@@ -44,4 +45,4 @@
   "engines": {
     "node": ">= 18"
   }
-}
+}

packages/@react-native-windows/automation-channel/windows/AutomationChannel/AutomationChannel.vcxproj

@@ -69,7 +69,7 @@
     <Import Project="PropertySheet.props" />
   </ImportGroup>
   <ImportGroup Label="ReactNativeWindowsPropertySheets">
-    <Import Project="$(ReactNativeWindowsDir)\PropertySheets\external\Microsoft.ReactNative.Uwp.CppLib.props" Condition="Exists('$(ReactNativeWindowsDir)\PropertySheets\External\Microsoft.ReactNative.Uwp.CppLib.props')" />
+    <Import Project="$(ReactNativeWindowsDir)\PropertySheets\external\Microsoft.ReactNative.CppLib.props" Condition="Exists('$(ReactNativeWindowsDir)\PropertySheets\External\Microsoft.ReactNative.CppLib.props')" />
     <!-- Added since we build this project with Paper/Fabric. -->
     <Import Project="$(ReactNativeWindowsDir)\PropertySheets\NuGet.LockFile.props" />
   </ImportGroup>
@@ -143,13 +143,13 @@
   </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ReactNativeWindowsTargets">
-    <Import Project="$(ReactNativeWindowsDir)\PropertySheets\External\Microsoft.ReactNative.Uwp.CppLib.targets" Condition="Exists('$(ReactNativeWindowsDir)\PropertySheets\External\Microsoft.ReactNative.Uwp.CppLib.targets')" />
+    <Import Project="$(ReactNativeWindowsDir)\PropertySheets\External\Microsoft.ReactNative.CppLib.targets" Condition="Exists('$(ReactNativeWindowsDir)\PropertySheets\External\Microsoft.ReactNative.CppLib.targets')" />
   </ImportGroup>
   <Target Name="EnsureReactNativeWindowsTargets" BeforeTargets="PrepareForBuild">
     <PropertyGroup>
       <ErrorText>This project references targets in your node_modules\react-native-windows folder that are missing. The missing file is {0}.</ErrorText>
     </PropertyGroup>
-    <Error Condition="!Exists('$(ReactNativeWindowsDir)\PropertySheets\External\Microsoft.ReactNative.Uwp.CppLib.props')" Text="$([System.String]::Format('$(ErrorText)', '$(ReactNativeWindowsDir)\PropertySheets\External\Microsoft.ReactNative.Uwp.CppLib.props'))" />
-    <Error Condition="!Exists('$(ReactNativeWindowsDir)\PropertySheets\External\Microsoft.ReactNative.Uwp.CppLib.targets')" Text="$([System.String]::Format('$(ErrorText)', '$(ReactNativeWindowsDir)\PropertySheets\External\Microsoft.ReactNative.Uwp.CppLib.targets'))" />
+    <Error Condition="!Exists('$(ReactNativeWindowsDir)\PropertySheets\External\Microsoft.ReactNative.CppLib.props')" Text="$([System.String]::Format('$(ErrorText)', '$(ReactNativeWindowsDir)\PropertySheets\External\Microsoft.ReactNative.CppLib.props'))" />
+    <Error Condition="!Exists('$(ReactNativeWindowsDir)\PropertySheets\External\Microsoft.ReactNative.CppLib.targets')" Text="$([System.String]::Format('$(ErrorText)', '$(ReactNativeWindowsDir)\PropertySheets\External\Microsoft.ReactNative.CppLib.targets'))" />
   </Target>
 </Project>

packages/@react-native-windows/automation-channel/windows/AutomationChannel/packages.fabric.lock.json

@@ -2,6 +2,18 @@
   "version": 1,
   "dependencies": {
     "native,Version=v0.0": {
+      "boost": {
+        "type": "Direct",
+        "requested": "[1.83.0, )",
+        "resolved": "1.83.0",
+        "contentHash": "cy53VNMzysEMvhBixDe8ujPk67Fcj3v6FPHQnH91NYJNLHpc6jxa2xq9ruCaaJjE4M3YrGSHDi4uUSTGBWw6EQ=="
+      },
+      "Microsoft.VCRTForwarders.140": {
+        "type": "Direct",
+        "requested": "[1.0.2-rc, )",
+        "resolved": "1.0.2-rc",
+        "contentHash": "/r+sjtEeCIGyDhobIZ5hSmYhC/dSyGZxf1SxYJpElUhB0LMCktOMFs9gXrauXypIFECpVynNyVjAmJt6hjJ5oQ=="
+      },
       "Microsoft.Windows.CppWinRT": {
         "type": "Direct",
         "requested": "[2.0.230706.1, )",
@@ -18,11 +30,6 @@
           "Microsoft.Windows.SDK.BuildTools": "10.0.22621.756"
         }
       },
-      "boost": {
-        "type": "Transitive",
-        "resolved": "1.83.0",
-        "contentHash": "cy53VNMzysEMvhBixDe8ujPk67Fcj3v6FPHQnH91NYJNLHpc6jxa2xq9ruCaaJjE4M3YrGSHDi4uUSTGBWw6EQ=="
-      },
       "Microsoft.Build.Tasks.Git": {
         "type": "Transitive",
         "resolved": "1.1.1",
@@ -94,6 +101,12 @@
       }
     },
     "native,Version=v0.0/win10-arm": {
+      "Microsoft.VCRTForwarders.140": {
+        "type": "Direct",
+        "requested": "[1.0.2-rc, )",
+        "resolved": "1.0.2-rc",
+        "contentHash": "/r+sjtEeCIGyDhobIZ5hSmYhC/dSyGZxf1SxYJpElUhB0LMCktOMFs9gXrauXypIFECpVynNyVjAmJt6hjJ5oQ=="
+      },
       "Microsoft.WindowsAppSDK": {
         "type": "Direct",
         "requested": "[1.6.240923002, )",
@@ -111,6 +124,12 @@
       }
     },
     "native,Version=v0.0/win10-arm-aot": {
+      "Microsoft.VCRTForwarders.140": {
+        "type": "Direct",
+        "requested": "[1.0.2-rc, )",
+        "resolved": "1.0.2-rc",
+        "contentHash": "/r+sjtEeCIGyDhobIZ5hSmYhC/dSyGZxf1SxYJpElUhB0LMCktOMFs9gXrauXypIFECpVynNyVjAmJt6hjJ5oQ=="
+      },
       "Microsoft.WindowsAppSDK": {
         "type": "Direct",
         "requested": "[1.6.240923002, )",
@@ -128,6 +147,12 @@
       }
     },
     "native,Version=v0.0/win10-arm64-aot": {
+      "Microsoft.VCRTForwarders.140": {
+        "type": "Direct",
+        "requested": "[1.0.2-rc, )",
+        "resolved": "1.0.2-rc",
+        "contentHash": "/r+sjtEeCIGyDhobIZ5hSmYhC/dSyGZxf1SxYJpElUhB0LMCktOMFs9gXrauXypIFECpVynNyVjAmJt6hjJ5oQ=="
+      },
       "Microsoft.WindowsAppSDK": {
         "type": "Direct",
         "requested": "[1.6.240923002, )",
@@ -145,6 +170,12 @@
       }
     },
     "native,Version=v0.0/win10-x64": {
+      "Microsoft.VCRTForwarders.140": {
+        "type": "Direct",
+        "requested": "[1.0.2-rc, )",
+        "resolved": "1.0.2-rc",
+        "contentHash": "/r+sjtEeCIGyDhobIZ5hSmYhC/dSyGZxf1SxYJpElUhB0LMCktOMFs9gXrauXypIFECpVynNyVjAmJt6hjJ5oQ=="
+      },
       "Microsoft.WindowsAppSDK": {
         "type": "Direct",
         "requested": "[1.6.240923002, )",
@@ -162,6 +193,12 @@
       }
     },
     "native,Version=v0.0/win10-x64-aot": {
+      "Microsoft.VCRTForwarders.140": {
+        "type": "Direct",
+        "requested": "[1.0.2-rc, )",
+        "resolved": "1.0.2-rc",
+        "contentHash": "/r+sjtEeCIGyDhobIZ5hSmYhC/dSyGZxf1SxYJpElUhB0LMCktOMFs9gXrauXypIFECpVynNyVjAmJt6hjJ5oQ=="
+      },
       "Microsoft.WindowsAppSDK": {
         "type": "Direct",
         "requested": "[1.6.240923002, )",
@@ -179,6 +216,12 @@
       }
     },
     "native,Version=v0.0/win10-x86": {
+      "Microsoft.VCRTForwarders.140": {
+        "type": "Direct",
+        "requested": "[1.0.2-rc, )",
+        "resolved": "1.0.2-rc",
+        "contentHash": "/r+sjtEeCIGyDhobIZ5hSmYhC/dSyGZxf1SxYJpElUhB0LMCktOMFs9gXrauXypIFECpVynNyVjAmJt6hjJ5oQ=="
+      },
       "Microsoft.WindowsAppSDK": {
         "type": "Direct",
         "requested": "[1.6.240923002, )",
@@ -196,6 +239,12 @@
       }
     },
     "native,Version=v0.0/win10-x86-aot": {
+      "Microsoft.VCRTForwarders.140": {
+        "type": "Direct",
+        "requested": "[1.0.2-rc, )",
+        "resolved": "1.0.2-rc",
+        "contentHash": "/r+sjtEeCIGyDhobIZ5hSmYhC/dSyGZxf1SxYJpElUhB0LMCktOMFs9gXrauXypIFECpVynNyVjAmJt6hjJ5oQ=="
+      },
       "Microsoft.WindowsAppSDK": {
         "type": "Direct",
         "requested": "[1.6.240923002, )",

packages/@react-native-windows/automation-channel/windows/ExperimentalFeatures.props

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+
+  <PropertyGroup Label="Microsoft.ReactNative Experimental Features">
+    <RnwNewArch>false</RnwNewArch>
+    <UseExperimentalNuget>false</UseExperimentalNuget>
+
+    <ReactExperimentalFeaturesSet>true</ReactExperimentalFeaturesSet>
+  </PropertyGroup>
+
+</Project>

packages/@react-native-windows/codegen/src/generators/GenerateComponentWindows.ts

@@ -31,10 +31,14 @@ const headerTemplate = `/*
  */
 #pragma once
 
-#include <JSValueComposition.h>
 #include <NativeModules.h>
+
+#ifdef RNW_NEW_ARCH
+#include <JSValueComposition.h>
+
 #include <winrt/Microsoft.ReactNative.Composition.h>
-#include <winrt/Microsoft.UI.Composition.h>`;
+#include <winrt/Microsoft.UI.Composition.h>
+#endif // #ifdef RNW_NEW_ARCH`;
 
 const propsTemplate = `REACT_STRUCT(::_PROPS_NAME_::)
 struct ::_PROPS_NAME_:: : winrt::implements<::_PROPS_NAME_::, winrt::Microsoft::ReactNative::IComponentProps> {
@@ -229,6 +233,8 @@ void Register::_COMPONENT_NAME_::NativeComponent(
 const fileTemplate = `
 ${headerTemplate}
 
+#ifdef RNW_NEW_ARCH
+
 namespace ::_NAMESPACE_:: {
 
 ::_COMPONENT_PROP_OBJECT_TYPES_::
@@ -240,6 +246,8 @@ namespace ::_NAMESPACE_:: {
 
 ::_COMPONENT_REGISTRATION_::
 } // namespace ::_NAMESPACE_::
+
+#endif // #ifdef RNW_NEW_ARCH
 `;
 
 function capitalizeFirstLetter(s: string) {

packages/e2e-test-app-fabric/windows/ExperimentalFeatures.props

@@ -2,8 +2,9 @@
 <Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
 
   <PropertyGroup Label="Microsoft.ReactNative Experimental Features">
-    <UseFabric>true</UseFabric>
-    <UseWinUI3>true</UseWinUI3>
+    <RnwNewArch>true</RnwNewArch>
+    <UseExperimentalNuget>false</UseExperimentalNuget>
+
     <ReactExperimentalFeaturesSet>true</ReactExperimentalFeaturesSet>
   </PropertyGroup>
 

packages/e2e-test-app-fabric/windows/RNTesterApp-Fabric.Package/packages.lock.json

@@ -59,7 +59,9 @@
         "type": "Project",
         "dependencies": {
           "Microsoft.ReactNative": "[1.0.0, )",
-          "Microsoft.WindowsAppSDK": "[1.6.240923002, )"
+          "Microsoft.VCRTForwarders.140": "[1.0.2-rc, )",
+          "Microsoft.WindowsAppSDK": "[1.6.240923002, )",
+          "boost": "[1.83.0, )"
         }
       },
       "common": {

packages/e2e-test-app-fabric/windows/RNTesterApp-Fabric/RNTesterApp-Fabric.vcxproj

@@ -93,11 +93,6 @@
       <PreprocessorDefinitions>NDEBUG;%(PreprocessorDefinitions)</PreprocessorDefinitions>
     </ClCompile>
   </ItemDefinitionGroup>
-  <ItemDefinitionGroup>
-    <ClCompile>
-      <PreprocessorDefinitions Condition="'$(UseFabric)'=='true'">USE_FABRIC;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-    </ClCompile>
-  </ItemDefinitionGroup>
   <PropertyGroup Label="UserMacros" />
   <ItemGroup>
     <ClInclude Include="RNTesterApp-Fabric.h" />

packages/e2e-test-app-fabric/windows/RNTesterApp-Fabric/packages.lock.json

@@ -69,7 +69,9 @@
         "type": "Project",
         "dependencies": {
           "Microsoft.ReactNative": "[1.0.0, )",
-          "Microsoft.WindowsAppSDK": "[1.6.240923002, )"
+          "Microsoft.VCRTForwarders.140": "[1.0.2-rc, )",
+          "Microsoft.WindowsAppSDK": "[1.6.240923002, )",
+          "boost": "[1.83.0, )"
         }
       },
       "common": {