diff --git a/src/zip/ZipPack.cpp b/src/zip/ZipPack.cpp
index 77cdd3c..915d114 100644
--- a/src/zip/ZipPack.cpp
+++ b/src/zip/ZipPack.cpp
@@ -36,6 +36,13 @@ void my_zip_close(zip* file)
 	fs_zip_close(file);
 }
 
+uint64_t computePersistentHash(const AbsPath& path)
+{
+	uint64_t hash = 0;
+	for (const tl::string& e : path)
+		tl::hash_and_combine(hash, e);
+	return hash;
+}
 uint64_t computePersistentHash(AbsPathView path)
 {
 	uint64_t hash = 0;
diff --git a/src/zip/ZipUtils.cpp b/src/zip/ZipUtils.cpp
index 4b6339e..b2e979a 100644
--- a/src/zip/ZipUtils.cpp
+++ b/src/zip/ZipUtils.cpp
@@ -5,7 +5,6 @@
 #include "fs/WritableFolderPack.h"
 #include "fs/CopyStream.h"
 #include "fs/zip/ZipWriter.h"
-#include "fs/zip/DeflateFileWriter.h"
 
 namespace fs
 {