diff --git a/tools/cmakev2/build.cmake b/tools/cmakev2/build.cmake
index ab6d71ed0de..06c441a5db6 100644
--- a/tools/cmakev2/build.cmake
+++ b/tools/cmakev2/build.cmake
@@ -83,7 +83,12 @@ function(idf_build_get_property variable property)
     cmake_parse_arguments(ARG "${options}" "${one_value}" "${multi_value}" ${ARGN})
 
     if("${property}" STREQUAL BUILD_COMPONENTS)
-        idf_die("Build property 'BUILD_COMPONENTS' is not supported")
+        # BUILD_COMPONENTS is populated by the Build system v1 compatibility
+        # shim; reject only when running as a native Build system v2 project.
+        idf_build_get_property(_v1_compat __V1_COMPAT_SHIM)
+        if(NOT _v1_compat)
+            idf_die("Build property 'BUILD_COMPONENTS' is not supported")
+        endif()
     endif()
 
     set(genexpr)
diff --git a/tools/cmakev2/project.cmake b/tools/cmakev2/project.cmake
index bf63ddd2eaf..ae7816b9ce5 100644
--- a/tools/cmakev2/project.cmake
+++ b/tools/cmakev2/project.cmake
@@ -755,6 +755,40 @@ function(__project_default)
                          COMPONENTS ${root_components}
                          MAPFILE_TARGET "${executable}_mapfile")
 
+    # In Build system v1, the ``project_elf`` variable (set to
+    # "${project_name}.elf") is used by several app CMakeLists.txt files to add
+    # linker flags after project(). In Build system v2 the executable target
+    # is just "${executable}" (the .elf suffix is an output property, not part
+    # of the target name). Propagate it to the caller's scope so existing
+    # code keeps working.
+    set(project_elf "${executable}" PARENT_SCOPE)
+
+    # Provide Build system v1-compatible build properties so that existing
+    # test apps and project CMakeLists.txt files that query EXECUTABLE or
+    # BUILD_COMPONENTS continue to work when built through the shim.
+    idf_build_get_property(v1_compat __V1_COMPAT_SHIM)
+    if(v1_compat)
+        idf_build_set_property(EXECUTABLE "${executable}")
+        idf_build_set_property(EXECUTABLE_NAME "${executable}")
+
+        # BUILD_COMPONENTS: in Build system v1 this is the set of components
+        # actually processed during the build (COMPONENTS + their transitive
+        # REQUIRES within the restricted scope). Use LIBRARY_COMPONENTS_LINKED
+        # from the Build system v2 library target which reflects the actual
+        # list of components linked, plus the architecture component which
+        # Build system v1 always includes but Build system v2 does not track
+        # as a linked library.
+        get_target_property(library ${executable} LIBRARY_INTERFACE)
+        if(library)
+            idf_library_get_property(linked_components "${library}" LIBRARY_COMPONENTS_LINKED)
+            idf_build_get_property(target_arch IDF_TARGET_ARCH)
+            if(target_arch AND NOT target_arch IN_LIST linked_components)
+                list(APPEND linked_components ${target_arch})
+            endif()
+            idf_build_set_property(BUILD_COMPONENTS "${linked_components}")
+        endif()
+    endif()
+
     if(CONFIG_APP_BUILD_GENERATE_BINARIES AND TARGET idf::esptool_py)
         # Is it possible to have a configuration where
         # CONFIG_APP_BUILD_GENERATE_BINARIES is not set?