diff --git a/common/fake_prefs.h b/common/fake_prefs.h
index 7ae9fb9..721cf24 100644
--- a/common/fake_prefs.h
+++ b/common/fake_prefs.h
@@ -59,6 +59,9 @@
   void AddObserver(std::string_view key, ObserverInterface* observer) override;
   void RemoveObserver(std::string_view key,
                       ObserverInterface* observer) override;
+  bool StartTransaction() override { return false; }
+  bool CancelTransaction() override { return false; }
+  bool SubmitTransaction() override { return false; }
 
  private:
   enum class PrefType {
diff --git a/common/mock_prefs.h b/common/mock_prefs.h
index f308074..028650d 100644
--- a/common/mock_prefs.h
+++ b/common/mock_prefs.h
@@ -47,6 +47,9 @@
 
   MOCK_METHOD2(AddObserver, void(std::string_view key, ObserverInterface*));
   MOCK_METHOD2(RemoveObserver, void(std::string_view key, ObserverInterface*));
+  MOCK_METHOD(bool, StartTransaction, (), (override));
+  MOCK_METHOD(bool, CancelTransaction, (), (override));
+  MOCK_METHOD(bool, SubmitTransaction, (), (override));
 };
 
 }  // namespace chromeos_update_engine
diff --git a/common/prefs.cc b/common/prefs.cc
index a070302..57d4dcd 100644
--- a/common/prefs.cc
+++ b/common/prefs.cc
@@ -17,6 +17,8 @@
 #include "update_engine/common/prefs.h"
 
 #include <algorithm>
+#include <filesystem>
+#include <unistd.h>
 
 #include <base/files/file_enumerator.h>
 #include <base/files/file_util.h>
@@ -25,6 +27,7 @@
 #include <base/strings/string_split.h>
 #include <base/strings/string_util.h>
 
+#include "update_engine/common/platform_constants.h"
 #include "update_engine/common/utils.h"
 
 using std::string;
@@ -160,8 +163,62 @@
   return file_storage_.Init(prefs_dir);
 }
 
+bool PrefsBase::StartTransaction() {
+  return storage_->CreateTemporaryPrefs();
+}
+
+bool PrefsBase::CancelTransaction() {
+  return storage_->DeleteTemporaryPrefs();
+}
+
+bool PrefsBase::SubmitTransaction() {
+  return storage_->SwapPrefs();
+}
+
+std::string Prefs::FileStorage::GetTemporaryDir() const {
+  return prefs_dir_.value() + "_tmp";
+}
+
+bool Prefs::FileStorage::CreateTemporaryPrefs() {
+  // Delete any existing prefs_tmp
+  DeleteTemporaryPrefs();
+  // Get the paths to the source and destination directories.
+  std::filesystem::path source_directory(prefs_dir_.value());
+  std::filesystem::path destination_directory(GetTemporaryDir());
+
+  if (!std::filesystem::exists(source_directory)) {
+    LOG(ERROR) << "prefs directory does not exist: " << source_directory;
+    return false;
+  }
+  // Copy the directory.
+  std::filesystem::copy(source_directory, destination_directory);
+
+  return true;
+}
+
+bool Prefs::FileStorage::DeleteTemporaryPrefs() {
+  std::filesystem::path destination_directory(GetTemporaryDir());
+
+  if (std::filesystem::exists(destination_directory)) {
+    return std::filesystem::remove_all(destination_directory);
+  }
+  return true;
+}
+
+bool Prefs::FileStorage::SwapPrefs() {
+  if (std::filesystem::exists(prefs_dir_.value())) {
+    std::filesystem::remove_all(prefs_dir_.value());
+  }
+  if (rename(GetTemporaryDir().c_str(), prefs_dir_.value().c_str()) != 0) {
+    LOG(ERROR) << "Error replacing prefs with prefs_tmp" << strerror(errno);
+    return false;
+  }
+  return true;
+}
+
 bool Prefs::FileStorage::Init(const base::FilePath& prefs_dir) {
   prefs_dir_ = prefs_dir;
+
   // Delete empty directories. Ignore errors when deleting empty directories.
   DeleteEmptyDirectories(prefs_dir_);
   return true;
@@ -231,8 +288,14 @@
   for (char c : key)
     TEST_AND_RETURN_FALSE(base::IsAsciiAlpha(c) || base::IsAsciiDigit(c) ||
                           c == '_' || c == '-' || c == kKeySeparator);
-  *filename = prefs_dir_.Append(
-      base::FilePath::StringPieceType(key.data(), key.size()));
+  if (std::filesystem::exists(GetTemporaryDir())) {
+    *filename =
+        base::FilePath(GetTemporaryDir())
+            .Append(base::FilePath::StringPieceType(key.data(), key.size()));
+  } else {
+    *filename = prefs_dir_.Append(
+        base::FilePath::StringPieceType(key.data(), key.size()));
+  }
   return true;
 }
 
diff --git a/common/prefs.h b/common/prefs.h
index c3105c6..d32e732 100644
--- a/common/prefs.h
+++ b/common/prefs.h
@@ -60,6 +60,17 @@
     // key was deleted.
     virtual bool DeleteKey(std::string_view key) = 0;
 
+    // Makes a copy of prefs directory called prefs_tmp, which is modified
+    // during update_engine checkpointing
+    virtual bool CreateTemporaryPrefs() { return false; }
+
+    // Deletes prefs_tmp directory
+    virtual bool DeleteTemporaryPrefs() { return false; }
+
+    // Replaces prefs with prefs_tmp to make update_engine checkpointing more
+    // atomic
+    virtual bool SwapPrefs() { return false; }
+
    private:
     DISALLOW_COPY_AND_ASSIGN(StorageInterface);
   };
@@ -73,6 +84,9 @@
   bool SetInt64(std::string_view key, const int64_t value) override;
   bool GetBoolean(std::string_view key, bool* value) const override;
   bool SetBoolean(std::string_view key, const bool value) override;
+  bool StartTransaction() override;
+  bool CancelTransaction() override;
+  bool SubmitTransaction() override;
 
   bool Exists(std::string_view key) const override;
   bool Delete(std::string_view key) override;
@@ -128,6 +142,9 @@
     bool SetKey(std::string_view key, std::string_view value) override;
     bool KeyExists(std::string_view key) const override;
     bool DeleteKey(std::string_view key) override;
+    bool CreateTemporaryPrefs() override;
+    bool DeleteTemporaryPrefs() override;
+    bool SwapPrefs() override;
 
    private:
     FRIEND_TEST(PrefsTest, GetFileNameForKey);
@@ -139,6 +156,9 @@
     bool GetFileNameForKey(std::string_view key,
                            base::FilePath* filename) const;
 
+    // Returns path of prefs_tmp used during update_engine checkpointing
+    std::string GetTemporaryDir() const;
+
     // Preference store directory.
     base::FilePath prefs_dir_;
   };
diff --git a/common/prefs_interface.h b/common/prefs_interface.h
index 69ccf68..d56435f 100644
--- a/common/prefs_interface.h
+++ b/common/prefs_interface.h
@@ -105,6 +105,17 @@
   virtual void RemoveObserver(std::string_view key,
                               ObserverInterface* observer) = 0;
 
+  // create tmp_prefs to write to during checkpointing. Flush will replace prefs
+  // with tmp_prefs
+  virtual bool StartTransaction() = 0;
+
+  // cancel any pending transaction by deleting tmp_prefs
+  virtual bool CancelTransaction() = 0;
+
+  // swap prefs with tmp_prefs checkpointing will use new tmp prefs to resume
+  // updates, otherwise we fall back on old prefs
+  virtual bool SubmitTransaction() = 0;
+
  protected:
   // Key separator used to create sub key and get file names,
   static const char kKeySeparator = '/';