diff --git a/build/cmake_deps.toml b/build/cmake_deps.toml
index 4811563269c..b1ed81b6a7e 100644
--- a/build/cmake_deps.toml
+++ b/build/cmake_deps.toml
@@ -58,6 +58,21 @@ deps = [
   "executorch_core",
 ]
 
+# HACK: prevent reduce_util from also showing up in custom_ops. The
+# actual medium-term fix is to stop using Buck to drive our CMake
+# builds.
+[targets.reduce_util]
+buck_targets = [
+  "//kernels/portable/cpu/util:reduce_util",
+]
+filters = [
+  ".cpp$",
+]
+deps = [
+  "executorch",
+  "executorch_core",
+]
+
 [targets.optimized_kernels]
 buck_targets = [
   "//kernels/optimized:generated_lib",
@@ -414,6 +429,7 @@ deps = [
   "optimized_kernels",
   "extension_parallel",
   "extension_threadpool",
+  "reduce_util",
   "xnnpack_backend",
 ]
 
diff --git a/build/executorch-config.cmake b/build/executorch-config.cmake
index 2c459b66ac8..e2cff7da6b5 100644
--- a/build/executorch-config.cmake
+++ b/build/executorch-config.cmake
@@ -65,6 +65,7 @@ set(lib_list
     neuron_backend
     qnn_executorch_backend
     portable_ops_lib
+    custom_ops
     extension_module
     extension_module_static
     extension_parallel
diff --git a/examples/models/llama/CMakeLists.txt b/examples/models/llama/CMakeLists.txt
index 5f49581ea25..67cf2f446a3 100644
--- a/examples/models/llama/CMakeLists.txt
+++ b/examples/models/llama/CMakeLists.txt
@@ -15,7 +15,7 @@
 # ~~~
 # It should also be cmake-lint clean.
 #
-cmake_minimum_required(VERSION 3.19)
+cmake_minimum_required(VERSION 3.24)  # 3.24 is required for WHOLE_ARCHIVE
 project(llama_runner)
 
 # Duplicating options as root CMakeLists.txt
@@ -84,14 +84,6 @@ if(CMAKE_TOOLCHAIN_IOS OR ANDROID)
   target_link_options_shared_lib(executorch)
 endif()
 
-# custom ops library
-if(EXECUTORCH_BUILD_KERNELS_CUSTOM)
-  add_subdirectory(
-    ${CMAKE_CURRENT_SOURCE_DIR}/../../../extension/llm/custom_ops
-    ${CMAKE_CURRENT_BINARY_DIR}/../../../extension/llm/custom_ops
-  )
-endif()
-
 # llama_runner library
 add_subdirectory(runner)
 
@@ -119,8 +111,7 @@ target_link_options_shared_lib(quantized_ops_lib)
 list(APPEND link_libraries quantized_kernels quantized_ops_lib)
 
 if(EXECUTORCH_BUILD_KERNELS_CUSTOM)
-  target_link_options_shared_lib(custom_ops)
-  list(APPEND link_libraries custom_ops)
+  list(APPEND link_libraries $<LINK_LIBRARY:WHOLE_ARCHIVE,custom_ops>)
 endif()
 
 if(EXECUTORCH_BUILD_TORCHAO)
diff --git a/examples/models/llava/CMakeLists.txt b/examples/models/llava/CMakeLists.txt
index ecd00809fdb..f7fa4bacc04 100644
--- a/examples/models/llava/CMakeLists.txt
+++ b/examples/models/llava/CMakeLists.txt
@@ -93,14 +93,6 @@ if(CMAKE_TOOLCHAIN_IOS OR ANDROID)
   target_link_options_shared_lib(executorch)
 endif()
 
-# custom ops library
-if(EXECUTORCH_BUILD_KERNELS_CUSTOM)
-  add_subdirectory(
-    ${EXECUTORCH_ROOT}/extension/llm/custom_ops
-    ${CMAKE_CURRENT_BINARY_DIR}/../../../extension/llm/custom_ops
-  )
-endif()
-
 # llava_runner library
 add_subdirectory(runner)
 
@@ -132,7 +124,6 @@ target_link_options_shared_lib(quantized_ops_lib)
 list(APPEND link_libraries quantized_kernels quantized_ops_lib)
 
 if(EXECUTORCH_BUILD_KERNELS_CUSTOM)
-  target_link_options_shared_lib(custom_ops)
   list(APPEND link_libraries custom_ops)
 endif()
 
diff --git a/extension/android/CMakeLists.txt b/extension/android/CMakeLists.txt
index 70f21f2751c..322d944bb38 100644
--- a/extension/android/CMakeLists.txt
+++ b/extension/android/CMakeLists.txt
@@ -4,7 +4,7 @@
 # This source code is licensed under the BSD-style license found in the
 # LICENSE file in the root directory of this source tree.
 
-cmake_minimum_required(VERSION 3.19)
+cmake_minimum_required(VERSION 3.24) # 3.24 is required for WHOLE_ARCHIVE
 
 project(executorch_jni)
 
@@ -115,12 +115,7 @@ if(TARGET vulkan_backend)
 endif()
 
 if(EXECUTORCH_BUILD_KERNELS_CUSTOM)
-  add_subdirectory(
-    ${EXECUTORCH_ROOT}/extension/llm/custom_ops
-    ${CMAKE_CURRENT_BINARY_DIR}/../../extension/llm/custom_ops
-  )
-  list(APPEND link_libraries custom_ops)
-  target_link_options_shared_lib(custom_ops)
+  list(APPEND link_libraries $<LINK_LIBRARY:WHOLE_ARCHIVE,custom_ops>)
 endif()
 
 if(TARGET pthreadpool)