diff --git a/Sources/CMakeLists.txt b/Sources/CMakeLists.txt
index f7f7ba156..ad8ecf178 100644
--- a/Sources/CMakeLists.txt
+++ b/Sources/CMakeLists.txt
@@ -12,12 +12,31 @@
 ##
 ##===----------------------------------------------------------------------===##
 
-add_subdirectory(_FoundationCShims)
-
-# Disable the macro build on Windows until we can correctly build it for the host architecture
-if(NOT CMAKE_SYSTEM_NAME STREQUAL Windows)
-	add_subdirectory(FoundationMacros)
+include(ExternalProject)
+if(CMAKE_HOST_WIN32)
+  set(_flags "-use-ld=lld")
+  if(DEFINED CMAKE_HOST_Swift_FLAGS)
+    set(_flags "${_flags} ${CMAKE_HOST_Swift_FLAGS}")
+  endif()
+  set(_FoundationMacrosSwiftFlags "-DCMAKE_Swift_FLAGS=${_flags}")
+endif()
+ExternalProject_Add(FoundationMacros
+  SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/FoundationMacros"
+  PREFIX "${CMAKE_BINARY_DIR}/_deps"
+  BINARY_DIR "macros"
+  CMAKE_ARGS
+    -DCMAKE_MAKE_PROGRAM=${CMAKE_MAKE_PROGRAM}
+    ${_FoundationMacrosSwiftFlags}
+  INSTALL_COMMAND "")
+ExternalProject_Get_Property(FoundationMacros BINARY_DIR)
+if(CMAKE_HOST_WIN32)
+  set(_SwiftFoundation_PredicateMacro "${BINARY_DIR}/FoundationMacros.exe#PredicateMacro")
+  set(_SwiftFoundation_ExpressionMacro "${BINARY_DIR}/FoundationMacros.exe#ExpressionMacro")
+else()
+  set(_SwiftFoundation_PredicateMacro "${BINARY_DIR}/FoundationMacros#PredicateMacro")
+  set(_SwiftFoundation_ExpressionMacro "${BINARY_DIR}/FoundationMacros#ExpressionMacro")
 endif()
 
+add_subdirectory(_FoundationCShims)
 add_subdirectory(FoundationEssentials)
 add_subdirectory(FoundationInternationalization)
diff --git a/Sources/FoundationMacros/CMakeLists.txt b/Sources/FoundationMacros/CMakeLists.txt
index bbc7bd628..239dd6c44 100644
--- a/Sources/FoundationMacros/CMakeLists.txt
+++ b/Sources/FoundationMacros/CMakeLists.txt
@@ -12,10 +12,25 @@
 ##
 ##===----------------------------------------------------------------------===##
 
+cmake_minimum_required(VERSION 3.22)
+
+if(POLICY CMP0156)
+    # Deduplicate linked libraries where appropriate
+    cmake_policy(SET CMP0156 NEW)
+endif()
+if(POLICY CMP0157)
+    # New Swift build model: improved incremental build performance and LSP support
+  cmake_policy(SET CMP0157 NEW)
+endif()
+
+project(FoundationMacros
+  LANGUAGES Swift)
+
 # SwiftSyntax Dependency
-include(FetchContent)
 find_package(SwiftSyntax)
 if(NOT SwiftSyntax_FOUND)
+    include(FetchContent)
+
     # If building at desk, check out and link against the SwiftSyntax repo's targets
     FetchContent_Declare(SwiftSyntax
         GIT_REPOSITORY https://github.com/swiftlang/swift-syntax.git