diff --git a/extension/flat_tensor/serialize/BUCK b/extension/flat_tensor/serialize/BUCK
index 08e83a5f3c4..04fb1146c33 100644
--- a/extension/flat_tensor/serialize/BUCK
+++ b/extension/flat_tensor/serialize/BUCK
@@ -1,6 +1,44 @@
+load("@fbcode_macros//build_defs:build_file_migration.bzl", "fbcode_target", "non_fbcode_target")
 load("@fbsource//xplat/executorch/build:runtime_wrapper.bzl", "runtime")
 load(":targets.bzl", "define_common_targets")
 
 oncall("executorch")
 
-define_common_targets()
+non_fbcode_target(_kind = define_common_targets,)
+
+# !!!! fbcode/executorch/extension/flat_tensor/serialize/TARGETS was merged into this file, see https://fburl.com/workplace/xl8l9yuo for more info !!!!
+
+load("@fbsource//xplat/executorch/build:runtime_wrapper.bzl", "runtime")
+load(":targets.bzl", "define_common_targets")
+
+
+fbcode_target(_kind = define_common_targets,)
+
+fbcode_target(_kind = runtime.python_library,
+    name = "schema",
+    srcs = [
+        "flat_tensor_schema.py",
+    ],
+    visibility = [
+        "//executorch/...",
+    ],
+    deps = [
+        "//executorch/exir:tensor_layout",
+    ]
+)
+
+fbcode_target(_kind = runtime.python_library,
+    name = "serialize",
+    srcs = [
+        "serialize.py",
+    ],
+    resources = [
+        "flat_tensor.fbs",
+        "scalar_type.fbs",
+    ],
+    visibility = ["PUBLIC"],
+    deps = [
+        ":schema",
+        "//executorch/exir/_serialize:lib",
+    ],
+)
diff --git a/extension/flat_tensor/serialize/TARGETS b/extension/flat_tensor/serialize/TARGETS
deleted file mode 100644
index c33004d59aa..00000000000
--- a/extension/flat_tensor/serialize/TARGETS
+++ /dev/null
@@ -1,35 +0,0 @@
-load("@fbsource//xplat/executorch/build:runtime_wrapper.bzl", "runtime")
-load(":targets.bzl", "define_common_targets")
-
-oncall("executorch")
-
-define_common_targets()
-
-runtime.python_library(
-    name = "schema",
-    srcs = [
-        "flat_tensor_schema.py",
-    ],
-    visibility = [
-        "//executorch/...",
-    ],
-    deps = [
-        "//executorch/exir:tensor_layout",
-    ]
-)
-
-runtime.python_library(
-    name = "serialize",
-    srcs = [
-        "serialize.py",
-    ],
-    resources = [
-        "flat_tensor.fbs",
-        "scalar_type.fbs",
-    ],
-    visibility = ["PUBLIC"],
-    deps = [
-        ":schema",
-        "//executorch/exir/_serialize:lib",
-    ],
-)
diff --git a/extension/flat_tensor/test/BUCK b/extension/flat_tensor/test/BUCK
index 1e8cc179228..63f23d6c6d0 100644
--- a/extension/flat_tensor/test/BUCK
+++ b/extension/flat_tensor/test/BUCK
@@ -1,8 +1,31 @@
+load("@fbcode_macros//build_defs:build_file_migration.bzl", "fbcode_target", "non_fbcode_target")
+oncall("executorch")
 # Any targets that should be shared between fbcode and xplat must be defined in
 # targets.bzl. This file can contain xplat-only targets.
 
 load(":targets.bzl", "define_common_targets")
 
-oncall("executorch")
 
-define_common_targets()
+non_fbcode_target(_kind = define_common_targets,)
+
+# !!!! fbcode/executorch/extension/flat_tensor/test/TARGETS was merged into this file, see https://fburl.com/workplace/xl8l9yuo for more info !!!!
+
+# Any targets that should be shared between fbcode and xplat must be defined in
+# targets.bzl. This file can contain fbcode-only targets.
+
+load("@fbcode_macros//build_defs:python_unittest.bzl", "python_unittest")
+load(":targets.bzl", "define_common_targets")
+
+
+fbcode_target(_kind = define_common_targets,is_fbcode=True)
+
+fbcode_target(_kind = python_unittest,
+    name = "serialize",
+    srcs = [
+        "test_serialize.py",
+    ],
+    deps = [
+        "//executorch/extension/flat_tensor/serialize:serialize",
+        "//executorch/extension/flat_tensor/serialize:schema",
+    ],
+)
diff --git a/extension/flat_tensor/test/TARGETS b/extension/flat_tensor/test/TARGETS
deleted file mode 100644
index 0dc97974af8..00000000000
--- a/extension/flat_tensor/test/TARGETS
+++ /dev/null
@@ -1,20 +0,0 @@
-# Any targets that should be shared between fbcode and xplat must be defined in
-# targets.bzl. This file can contain fbcode-only targets.
-
-load("@fbcode_macros//build_defs:python_unittest.bzl", "python_unittest")
-load(":targets.bzl", "define_common_targets")
-
-oncall("executorch")
-
-define_common_targets(is_fbcode=True)
-
-python_unittest(
-    name = "serialize",
-    srcs = [
-        "test_serialize.py",
-    ],
-    deps = [
-        "//executorch/extension/flat_tensor/serialize:serialize",
-        "//executorch/extension/flat_tensor/serialize:schema",
-    ],
-)
diff --git a/extension/kernel_util/BUCK b/extension/kernel_util/BUCK
index 1e8cc179228..5dcaa305865 100644
--- a/extension/kernel_util/BUCK
+++ b/extension/kernel_util/BUCK
@@ -1,8 +1,19 @@
+load("@fbcode_macros//build_defs:build_file_migration.bzl", "fbcode_target", "non_fbcode_target")
+oncall("executorch")
 # Any targets that should be shared between fbcode and xplat must be defined in
 # targets.bzl. This file can contain xplat-only targets.
 
 load(":targets.bzl", "define_common_targets")
 
-oncall("executorch")
 
-define_common_targets()
+non_fbcode_target(_kind = define_common_targets,)
+
+# !!!! fbcode/executorch/extension/kernel_util/TARGETS was merged into this file, see https://fburl.com/workplace/xl8l9yuo for more info !!!!
+
+# Any targets that should be shared between fbcode and xplat must be defined in
+# targets.bzl. This file can contain fbcode-only targets.
+
+load(":targets.bzl", "define_common_targets")
+
+
+fbcode_target(_kind = define_common_targets,)
diff --git a/extension/kernel_util/TARGETS b/extension/kernel_util/TARGETS
deleted file mode 100644
index 2341af9282f..00000000000
--- a/extension/kernel_util/TARGETS
+++ /dev/null
@@ -1,8 +0,0 @@
-# Any targets that should be shared between fbcode and xplat must be defined in
-# targets.bzl. This file can contain fbcode-only targets.
-
-load(":targets.bzl", "define_common_targets")
-
-oncall("executorch")
-
-define_common_targets()