diff --git a/filesystem/filesystem.go b/filesystem/filesystem.go
index abc656f..64a2e23 100644
--- a/filesystem/filesystem.go
+++ b/filesystem/filesystem.go
@@ -19,6 +19,7 @@
 	"fmt"
 	"io"
 	"path/filepath"
+	"slices"
 	"strings"
 
 	"android/soong/android"
@@ -109,6 +110,12 @@
 
 	// Mount point for this image. Default is "/"
 	Mount_point *string
+
+	// If set to the name of a partition ("system", "vendor", etc), this filesystem module
+	// will also include the contents of the make-built staging directories. If any soong
+	// modules would be installed to the same location as a make module, they will overwrite
+	// the make version.
+	Include_make_built_files string
 }
 
 // android_filesystem packages a set of modules and their transitive dependencies into a filesystem
@@ -214,22 +221,21 @@
 	}
 
 	// create extra files if there's any
-	rootForExtraFiles := android.PathForModuleGen(ctx, "root-extra").OutputPath
-	var extraFiles android.OutputPaths
 	if f.buildExtraFiles != nil {
-		extraFiles = f.buildExtraFiles(ctx, rootForExtraFiles)
-	}
-
-	for _, f := range extraFiles {
-		rel, err := filepath.Rel(rootForExtraFiles.String(), f.String())
-		if err != nil || strings.HasPrefix(rel, "..") {
-			ctx.ModuleErrorf("can't make %q relative to %q", f, rootForExtraFiles)
-			continue
+		rootForExtraFiles := android.PathForModuleGen(ctx, "root-extra").OutputPath
+		extraFiles := f.buildExtraFiles(ctx, rootForExtraFiles)
+		for _, f := range extraFiles {
+			rel, err := filepath.Rel(rootForExtraFiles.String(), f.String())
+			if err != nil || strings.HasPrefix(rel, "..") {
+				ctx.ModuleErrorf("can't make %q relative to %q", f, rootForExtraFiles)
+			}
 		}
-		dst := rootDir.Join(ctx, rel)
-		builder.Command().Textf("(! [ -e %s -o -L %s ] || (echo \"%s already exists from an earlier stage of the build\" && exit 1))", dst, dst, dst)
-		builder.Command().Text("mkdir -p").Text(filepath.Dir(dst.String()))
-		builder.Command().Text("cp -P").Input(f).Output(dst)
+		if len(extraFiles) > 0 {
+			builder.Command().BuiltTool("merge_directories").
+				Implicits(extraFiles.Paths()).
+				Text(rootDir.String()).
+				Text(rootForExtraFiles.String())
+		}
 	}
 }
 
@@ -245,6 +251,7 @@
 	f.entries = f.CopySpecsToDir(ctx, builder, f.gatherFilteredPackagingSpecs(ctx), rebasedDir)
 
 	f.buildNonDepsFiles(ctx, builder, rootDir)
+	f.addMakeBuiltFiles(ctx, builder, rootDir)
 
 	// run host_init_verifier
 	// Ideally we should have a concept of pluggable linters that verify the generated image.
@@ -362,6 +369,10 @@
 		ctx.PropertyErrorf("file_contexts", "file_contexts is not supported for compressed cpio image.")
 	}
 
+	if f.properties.Include_make_built_files != "" {
+		ctx.PropertyErrorf("include_make_built_files", "include_make_built_files is not supported for compressed cpio image.")
+	}
+
 	rootDir := android.PathForModuleOut(ctx, "root").OutputPath
 	rebasedDir := rootDir
 	if f.properties.Base_dir != nil {
@@ -395,6 +406,41 @@
 	return output
 }
 
+var validPartitions = []string{
+	"system",
+	"userdata",
+	"cache",
+	"system_other",
+	"vendor",
+	"product",
+	"system_ext",
+	"odm",
+	"vendor_dlkm",
+	"odm_dlkm",
+	"system_dlkm",
+}
+
+func (f *filesystem) addMakeBuiltFiles(ctx android.ModuleContext, builder *android.RuleBuilder, rootDir android.Path) {
+	partition := f.properties.Include_make_built_files
+	if partition == "" {
+		return
+	}
+	if !slices.Contains(validPartitions, partition) {
+		ctx.PropertyErrorf("include_make_built_files", "Expected one of %#v, found %q", validPartitions, partition)
+		return
+	}
+	stampFile := fmt.Sprintf("target/product/%s/obj/PACKAGING/%s_intermediates/staging_dir.stamp", ctx.Config().DeviceName(), partition)
+	fileListFile := fmt.Sprintf("target/product/%s/obj/PACKAGING/%s_intermediates/file_list.txt", ctx.Config().DeviceName(), partition)
+	stagingDir := fmt.Sprintf("target/product/%s/%s", ctx.Config().DeviceName(), partition)
+
+	builder.Command().BuiltTool("merge_directories").
+		Implicit(android.PathForArbitraryOutput(ctx, stampFile)).
+		Text("--ignore-duplicates").
+		FlagWithInput("--file-list", android.PathForArbitraryOutput(ctx, fileListFile)).
+		Text(rootDir.String()).
+		Text(android.PathForArbitraryOutput(ctx, stagingDir).String())
+}
+
 var _ android.AndroidMkEntriesProvider = (*filesystem)(nil)
 
 // Implements android.AndroidMkEntriesProvider
diff --git a/filesystem/filesystem_test.go b/filesystem/filesystem_test.go
index f09ed08..6d62746 100644
--- a/filesystem/filesystem_test.go
+++ b/filesystem/filesystem_test.go
@@ -16,6 +16,7 @@
 
 import (
 	"os"
+	"path/filepath"
 	"testing"
 
 	"android/soong/android"
@@ -93,6 +94,22 @@
 	}
 }
 
+func TestIncludeMakeBuiltFiles(t *testing.T) {
+	result := fixture.RunTestWithBp(t, `
+		android_filesystem {
+			name: "myfilesystem",
+			include_make_built_files: "system",
+		}
+	`)
+
+	output := result.ModuleForTests("myfilesystem", "android_common").Output("myfilesystem.img")
+
+	stampFile := filepath.Join(result.Config.OutDir(), "target/product/test_device/obj/PACKAGING/system_intermediates/staging_dir.stamp")
+	fileListFile := filepath.Join(result.Config.OutDir(), "target/product/test_device/obj/PACKAGING/system_intermediates/file_list.txt")
+	android.AssertStringListContains(t, "deps of filesystem must include the staging dir stamp file", output.Implicits.Strings(), stampFile)
+	android.AssertStringListContains(t, "deps of filesystem must include the staging dir file list", output.Implicits.Strings(), fileListFile)
+}
+
 func TestFileSystemFillsLinkerConfigWithStubLibs(t *testing.T) {
 	result := fixture.RunTestWithBp(t, `
 		android_system_image {
diff --git a/scripts/Android.bp b/scripts/Android.bp
index e2fd59f..f36329b 100644
--- a/scripts/Android.bp
+++ b/scripts/Android.bp
@@ -292,3 +292,16 @@
     name: "keep-flagged-apis",
     src: "keep-flagged-apis.sh",
 }
+
+python_binary_host {
+    name: "merge_directories",
+    main: "merge_directories.py",
+    srcs: [
+        "merge_directories.py",
+    ],
+    version: {
+        py3: {
+            embedded_launcher: true,
+        },
+    },
+}
diff --git a/scripts/merge_directories.py b/scripts/merge_directories.py
new file mode 100755
index 0000000..3f8631b
--- /dev/null
+++ b/scripts/merge_directories.py
@@ -0,0 +1,60 @@
+#!/usr/bin/env python3
+import argparse
+import os
+import shutil
+import sys
+
+def main():
+    parser = argparse.ArgumentParser(
+        description="Given a list of directories, this script will copy the contents of all of "
+        "them into the first directory, erroring out if any duplicate files are found."
+    )
+    parser.add_argument(
+        "--ignore-duplicates",
+        action="store_true",
+        help="Don't error out on duplicate files, just skip them. The file from the earliest "
+        "directory listed on the command line will be the winner."
+    )
+    parser.add_argument(
+        "--file-list",
+        help="Path to a text file containing paths relative to in_dir. Only these paths will be "
+        "copied out of in_dir."
+    )
+    parser.add_argument("out_dir")
+    parser.add_argument("in_dir")
+    args = parser.parse_args()
+
+    if not os.path.isdir(args.out_dir):
+        sys.exit(f"error: {args.out_dir} must be a directory")
+    if not os.path.isdir(args.in_dir):
+        sys.exit(f"error: {args.in_dir} must be a directory")
+
+    file_list = None
+    if args.file_list:
+        with open(file_list_file, "r") as f:
+            file_list = f.read().strip().splitlines()
+
+    in_dir = args.in_dir
+    for root, dirs, files in os.walk(in_dir):
+        rel_root = os.path.relpath(root, in_dir)
+        dst_root = os.path.join(args.out_dir, rel_root)
+        made_parent_dirs = False
+        for f in files:
+            src = os.path.join(root, f)
+            dst = os.path.join(dst_root, f)
+            p = os.path.normpath(os.path.join(rel_root, f))
+            if file_list is not None and p not in file_list:
+                continue
+            if os.path.lexists(dst):
+                if args.ignore_duplicates:
+                    continue
+                sys.exit(f"error: {p} exists in both {args.out_dir} and {in_dir}")
+
+            if not made_parent_dirs:
+                os.makedirs(dst_root, exist_ok=True)
+                made_parent_dirs = True
+
+            shutil.copy2(src, dst, follow_symlinks=False)
+
+if __name__ == "__main__":
+    main()