Index: librime-1.14.0/CMakeLists.txt
===================================================================
--- librime-1.14.0.orig/CMakeLists.txt
+++ librime-1.14.0/CMakeLists.txt
@@ -60,7 +60,7 @@ if(MSVC)
 endif()
 
 if(LINUX)
-  find_package(Boost 1.74.0 REQUIRED COMPONENTS regex)
+  find_package(Boost 1.66.0 REQUIRED COMPONENTS regex filesystem)
 else()
   find_package(Boost 1.77.0)
 endif()
Index: librime-1.14.0/plugins/plugins_module.cc
===================================================================
--- librime-1.14.0.orig/plugins/plugins_module.cc
+++ librime-1.14.0/plugins/plugins_module.cc
@@ -6,7 +6,7 @@
 #include <algorithm>
 #include <boost/algorithm/string.hpp>
 #include <boost/dll.hpp>
-#include <filesystem>
+#include <boost/filesystem.hpp>
 #include <rime/build_config.h>
 #include <rime/common.h>
 #include <rime/component.h>
@@ -14,7 +14,7 @@
 #include <rime/registry.h>
 #include <rime_api.h>
 
-namespace fs = std::filesystem;
+namespace fs = boost::filesystem;
 
 namespace rime {
 
Index: librime-1.14.0/src/rime/common.h
===================================================================
--- librime-1.14.0.orig/src/rime/common.h
+++ librime-1.14.0/src/rime/common.h
@@ -9,7 +9,7 @@
 
 #include <rime/build_config.h>
 
-#include <filesystem>
+#include <boost/filesystem.hpp>
 #include <functional>
 #include <list>
 #include <map>
@@ -79,8 +79,9 @@ inline an<T> New(Args&&... args) {
 using boost::signals2::connection;
 using boost::signals2::signal;
 
-class path : public std::filesystem::path {
-  using fs_path = std::filesystem::path;
+class path : public boost::filesystem::path {
+
+  using fs_path = boost::filesystem::path;
 
  public:
   path() : fs_path() {}
@@ -89,9 +90,9 @@ class path : public std::filesystem::pat
 #ifdef _WIN32
   // convert utf-8 string to native encoding path.
   explicit path(const std::string& utf8_path)
-      : fs_path(std::filesystem::u8path(utf8_path)) {}
+      : fs_path(boost::filesystem::path(utf8_path)) {}
   explicit path(const char* utf8_path)
-      : fs_path(std::filesystem::u8path(utf8_path)) {}
+      : fs_path(boost::filesystem::path(utf8_path)) {}
 #else
   // disable implicit conversion from string to path for development purpose.
   explicit path(const std::string& utf8_path) : fs_path(utf8_path) {}
@@ -126,6 +127,9 @@ class path : public std::filesystem::pat
   friend path operator/(const fs_path& lhs, const char* rhs) {
     return path(lhs) /= path(rhs);
   }
+  const std::string & u8string() const {
+    return this->string();
+  }
 #ifdef RIME_ENABLE_LOGGING
   friend std::ostream& operator<<(std::ostream& os, const path& p) {
     return os << p.u8string();
Index: librime-1.14.0/src/rime/config/build_info_plugin.cc
===================================================================
--- librime-1.14.0.orig/src/rime/config/build_info_plugin.cc
+++ librime-1.14.0/src/rime/config/build_info_plugin.cc
@@ -2,7 +2,7 @@
 // Copyright RIME Developers
 // Distributed under the BSD License
 //
-#include <filesystem>
+#include <boost/filesystem.hpp>
 #include <rime/service.h>
 #include <rime/algo/fs.h>
 #include <rime/config/config_compiler.h>
@@ -37,7 +37,7 @@ bool BuildInfoPlugin::ReviewLinkOutput(C
     }
     // TODO: store as 64-bit number to avoid the year 2038 problem
     timestamps[resource->resource_id] =
-        (int)filesystem::to_time_t(std::filesystem::last_write_time(file_path));
+        (int)boost::filesystem::last_write_time(file_path);
   });
 #endif
   return true;
Index: librime-1.14.0/src/rime/config/config_data.cc
===================================================================
--- librime-1.14.0.orig/src/rime/config/config_data.cc
+++ librime-1.14.0/src/rime/config/config_data.cc
@@ -7,7 +7,7 @@
 #include <fstream>
 #include <sstream>
 #include <boost/algorithm/string.hpp>
-#include <filesystem>
+#include <boost/filesystem.hpp>
 #include <yaml-cpp/yaml.h>
 #include <rime/config/config_compiler.h>
 #include <rime/config/config_cow_ref.h>
@@ -65,8 +65,8 @@ bool ConfigData::LoadFromFile(const path
   file_path_ = file_path;
   modified_ = false;
   root.reset();
-  if (!std::filesystem::exists(file_path)) {
-    if (!boost::ends_with(file_path.u8string(), ".custom.yaml"))
+  if (!boost::filesystem::exists(file_path)) {
+    if (!boost::ends_with(file_path.string(), ".custom.yaml"))
       LOG(WARNING) << "nonexistent config file '" << file_path << "'.";
     return false;
   }
Index: librime-1.14.0/src/rime/dict/db.cc
===================================================================
--- librime-1.14.0.orig/src/rime/dict/db.cc
+++ librime-1.14.0/src/rime/dict/db.cc
@@ -5,7 +5,7 @@
 // 2011-11-02 GONG Chen <chen.sst@gmail.com>
 //
 #include <boost/algorithm/string.hpp>
-#include <filesystem>
+#include <boost/filesystem.hpp>
 #include <rime/common.h>
 #include <rime/resource.h>
 #include <rime/service.h>
@@ -40,7 +40,7 @@ Db::Db(const path& file_path, const stri
     : name_(name), file_path_(file_path) {}
 
 bool Db::Exists() const {
-  return std::filesystem::exists(file_path());
+  return boost::filesystem::exists(file_path());
 }
 
 bool Db::Remove() {
@@ -48,7 +48,7 @@ bool Db::Remove() {
     LOG(ERROR) << "attempt to remove opened db '" << name_ << "'.";
     return false;
   }
-  return std::filesystem::remove(file_path());
+  return boost::filesystem::remove(file_path());
 }
 
 bool Db::CreateMetadata() {
Index: librime-1.14.0/src/rime/dict/dict_compiler.cc
===================================================================
--- librime-1.14.0.orig/src/rime/dict/dict_compiler.cc
+++ librime-1.14.0/src/rime/dict/dict_compiler.cc
@@ -4,7 +4,7 @@
 //
 // 2011-11-27 GONG Chen <chen.sst@gmail.com>
 //
-#include <filesystem>
+#include <boost/filesystem.hpp>
 #include <cfloat>
 #include <cmath>
 #include <fstream>
@@ -51,7 +51,7 @@ static bool get_dict_files_from_settings
     for (auto it = tables->begin(); it != tables->end(); ++it) {
       string dict_name = As<ConfigValue>(*it)->str();
       auto dict_file = source_resolver->ResolvePath(dict_name + ".dict.yaml");
-      if (!std::filesystem::exists(dict_file)) {
+      if (!boost::filesystem::exists(dict_file)) {
         LOG(ERROR) << "source file '" << dict_file << "' does not exist.";
         return false;
       }
@@ -82,7 +82,7 @@ bool DictCompiler::Compile(const path& s
   bool build_table_from_source = true;
   DictSettings settings;
   auto dict_file = source_resolver_->ResolvePath(dict_name_ + ".dict.yaml");
-  if (!std::filesystem::exists(dict_file)) {
+  if (!boost::filesystem::exists(dict_file)) {
     LOG(ERROR) << "source file '" << dict_file << "' does not exist.";
     build_table_from_source = false;
   } else if (!load_dict_settings_from_file(&settings, dict_file)) {
@@ -165,7 +165,7 @@ bool DictCompiler::Compile(const path& s
     EntryCollector collector(std::move(syllabary));
     DictSettings settings;
     auto dict_file = source_resolver_->ResolvePath(pack_name + ".dict.yaml");
-    if (!std::filesystem::exists(dict_file)) {
+    if (!boost::filesystem::exists(dict_file)) {
       if (pack_table->Exists())
         LOG(INFO) << "pack source file '" << dict_file
                   << "' does not exist, using prebuilt table '"
@@ -209,7 +209,7 @@ bool DictCompiler::Compile(const path& s
 
 static path relocate_target(const path& source_path,
                             ResourceResolver* target_resolver) {
-  auto resource_id = source_path.filename().u8string();
+  auto resource_id = source_path.filename().string();
   return target_resolver->ResolvePath(resource_id);
 }
 
Index: librime-1.14.0/src/rime/dict/dictionary.cc
===================================================================
--- librime-1.14.0.orig/src/rime/dict/dictionary.cc
+++ librime-1.14.0/src/rime/dict/dictionary.cc
@@ -4,7 +4,7 @@
 //
 // 2011-07-05 GONG Chen <chen.sst@gmail.com>
 //
-#include <filesystem>
+#include <boost/filesystem.hpp>
 #include <rime/algo/syllabifier.h>
 #include <rime/common.h>
 #include <rime/dict/dictionary.h>
@@ -352,8 +352,8 @@ bool Dictionary::Decode(const Code& code
 }
 
 bool Dictionary::Exists() const {
-  return std::filesystem::exists(prism_->file_path()) && !tables_.empty() &&
-         std::filesystem::exists(tables_[0]->file_path());
+  return boost::filesystem::exists(prism_->file_path()) && !tables_.empty() &&
+         boost::filesystem::exists(tables_[0]->file_path());
 }
 
 bool Dictionary::Remove() {
Index: librime-1.14.0/src/rime/dict/mapped_file.cc
===================================================================
--- librime-1.14.0.orig/src/rime/dict/mapped_file.cc
+++ librime-1.14.0/src/rime/dict/mapped_file.cc
@@ -7,7 +7,7 @@
 // 2011-06-30 GONG Chen <chen.sst@gmail.com>
 //
 #include <fstream>
-#include <filesystem>
+#include <boost/filesystem.hpp>
 #include <boost/interprocess/file_mapping.hpp>
 #include <boost/interprocess/mapped_region.hpp>
 #include <rime/dict/mapped_file.h>
@@ -101,7 +101,7 @@ void MappedFile::Close() {
 }
 
 bool MappedFile::Exists() const {
-  return std::filesystem::exists(file_path_);
+  return boost::filesystem::exists(file_path_);
 }
 
 bool MappedFile::IsOpen() const {
@@ -130,7 +130,7 @@ bool MappedFile::Resize(size_t capacity)
   if (IsOpen())
     Close();
   try {
-    std::filesystem::resize_file(file_path_, capacity);
+    boost::filesystem::resize_file(file_path_, capacity);
   } catch (...) {
     return false;
   }
Index: librime-1.14.0/src/rime/dict/user_db.cc
===================================================================
--- librime-1.14.0.orig/src/rime/dict/user_db.cc
+++ librime-1.14.0/src/rime/dict/user_db.cc
@@ -107,7 +107,7 @@ bool UserDbHelper::UpdateUserInfo() {
 }
 
 bool UserDbHelper::IsUniformFormat(const path& file_path) {
-  return boost::ends_with(file_path.filename().u8string(),
+  return boost::ends_with(file_path.filename().string(),
                           plain_userdb_extension);
 }
 
Index: librime-1.14.0/src/rime/dict/user_db_recovery_task.cc
===================================================================
--- librime-1.14.0.orig/src/rime/dict/user_db_recovery_task.cc
+++ librime-1.14.0/src/rime/dict/user_db_recovery_task.cc
@@ -5,7 +5,7 @@
 // 2013-04-22 GONG Chen <chen.sst@gmail.com>
 //
 #include <boost/algorithm/string.hpp>
-#include <filesystem>
+#include <boost/filesystem.hpp>
 #include <boost/scope_exit.hpp>
 #include <rime/deployer.h>
 #include <rime/dict/db.h>
@@ -40,9 +40,9 @@ bool UserDbRecoveryTask::Run(Deployer* d
   // repair didn't work on the damaged db file; remove and recreate it
   LOG(INFO) << "recreating db file.";
   if (db_->Exists()) {
-    std::error_code ec;
-    std::filesystem::rename(db_->file_path(),
-                            path(db_->file_path()).concat(".old"), ec);
+    boost::system::error_code ec;
+    boost::filesystem::rename(db_->file_path(),
+                            path(db_->file_path()) /= ".old", ec);
     if (ec && !db_->Remove()) {
       LOG(ERROR) << "Error removing db file '" << db_->file_path() << "'.";
       return false;
@@ -67,12 +67,12 @@ void UserDbRecoveryTask::RestoreUserData
   const path& dir(deployer->user_data_sync_dir());
   // try *.userdb.txt
   path snapshot_path = dir / (dict_name + UserDb::snapshot_extension());
-  if (!std::filesystem::exists(snapshot_path)) {
+  if (!boost::filesystem::exists(snapshot_path)) {
     // try *.userdb.*.snapshot
     string legacy_snapshot_file =
         dict_name + component->extension() + ".snapshot";
     snapshot_path = dir / legacy_snapshot_file;
-    if (!std::filesystem::exists(snapshot_path)) {
+    if (!boost::filesystem::exists(snapshot_path)) {
       return;  // not found
     }
   }
Index: librime-1.14.0/src/rime/gear/simplifier.cc
===================================================================
--- librime-1.14.0.orig/src/rime/gear/simplifier.cc
+++ librime-1.14.0/src/rime/gear/simplifier.cc
@@ -36,7 +36,7 @@ class Opencc {
     opencc::Config config;
     try {
       // opencc accepts file path encoded in UTF-8.
-      converter_ = config.NewFromFile(config_path.u8string());
+      converter_ = config.NewFromFile(config_path.string());
 
       const list<opencc::ConversionPtr> conversions =
           converter_->GetConversionChain()->GetConversions();
@@ -305,7 +305,7 @@ Simplifier* SimplifierComponent::Create(
     return new Simplifier(ticket, opencc);
   }
   path opencc_config_path = path(opencc_config);
-  if (opencc_config_path.extension().u8string() == ".ini") {
+  if (opencc_config_path.extension().string() == ".ini") {
     LOG(ERROR) << "please upgrade opencc_config to an opencc 1.0 config file.";
     return nullptr;
   }
Index: librime-1.14.0/src/rime/lever/customizer.cc
===================================================================
--- librime-1.14.0.orig/src/rime/lever/customizer.cc
+++ librime-1.14.0/src/rime/lever/customizer.cc
@@ -4,14 +4,14 @@
 //
 // 2011-12-12 GONG Chen <chen.sst@gmail.com>
 //
-#include <filesystem>
+#include <boost/filesystem.hpp>
 #include <stdint.h>
 #include <rime/common.h>
 #include <rime/config.h>
 #include <rime/algo/utilities.h>
 #include <rime/lever/customizer.h>
 
-namespace fs = std::filesystem;
+namespace fs = boost::filesystem;
 
 namespace rime {
 
@@ -88,7 +88,7 @@ bool Customizer::UpdateConfigFile() {
   if (redistribute || (is_dirty && !missing_original_copy)) {
     try {
       fs::copy_file(source_path_, dest_path_,
-                    fs::copy_options::overwrite_existing);
+                    fs::copy_option::overwrite_if_exists);
     } catch (...) {
       LOG(ERROR) << "Error copying config file '" << source_path_
                  << "' to user directory.";
Index: librime-1.14.0/src/rime/lever/deployment_tasks.cc
===================================================================
--- librime-1.14.0.orig/src/rime/lever/deployment_tasks.cc
+++ librime-1.14.0/src/rime/lever/deployment_tasks.cc
@@ -9,7 +9,7 @@
 
 #include <algorithm>
 #include <boost/algorithm/string.hpp>
-#include <filesystem>
+#include <boost/filesystem.hpp>
 #include <boost/uuid/random_generator.hpp>
 #include <boost/uuid/uuid.hpp>
 #include <boost/uuid/uuid_io.hpp>
@@ -29,7 +29,7 @@
 #include <windows.h>
 #endif
 
-namespace fs = std::filesystem;
+namespace fs = boost::filesystem;
 
 namespace rime {
 
@@ -47,16 +47,16 @@ bool DetectModifications::Run(Deployer*
     for (auto dir : data_dirs_) {
       path p = fs::canonical(dir);
       last_modified = (std::max)(last_modified,
-                                 filesystem::to_time_t(fs::last_write_time(p)));
+                                 fs::last_write_time(p));
       if (fs::is_directory(p)) {
         for (fs::directory_iterator iter(p), end; iter != end; ++iter) {
           path entry(iter->path());
           if (fs::is_regular_file(fs::canonical(entry)) &&
-              entry.extension().u8string() == ".yaml" &&
-              entry.filename().u8string() != "user.yaml") {
+              entry.extension().string() == ".yaml" &&
+              entry.filename().string() != "user.yaml") {
             last_modified =
                 (std::max)(last_modified,
-                           filesystem::to_time_t(fs::last_write_time(entry)));
+                           fs::last_write_time(entry));
           }
         }
       }
@@ -85,7 +85,7 @@ bool InstallationUpdate::Run(Deployer* d
   const path& user_data_path(deployer->user_data_dir);
   if (!fs::exists(user_data_path)) {
     LOG(INFO) << "creating user data dir: " << user_data_path;
-    std::error_code ec;
+    boost::system::error_code ec;
     if (!fs::create_directories(user_data_path, ec)) {
       LOG(ERROR) << "Error creating user data dir: " << user_data_path;
     }
@@ -263,7 +263,7 @@ SchemaUpdate::SchemaUpdate(TaskInitializ
 }
 
 static bool MaybeCreateDirectory(path dir) {
-  std::error_code ec;
+  boost::system::error_code ec;
   if (fs::create_directories(dir, ec)) {
     return true;
   }
@@ -314,7 +314,7 @@ static bool TrashDeprecatedUserCopy(cons
       return false;
     }
     path backup = trash / user_copy.filename();
-    std::error_code ec;
+    boost::system::error_code ec;
     fs::rename(user_copy, backup, ec);
     if (ec) {
       LOG(ERROR) << "error trashing file " << user_copy;
@@ -419,7 +419,7 @@ static bool ConfigNeedsUpdate(Config* co
       continue;
     }
     if (recorded_time !=
-        (int)filesystem::to_time_t(fs::last_write_time(source_file))) {
+        (int)fs::last_write_time(source_file)) {
       LOG(INFO) << "source file " << (recorded_time ? "changed: " : "added: ")
                 << source_file;
       return true;
@@ -460,7 +460,7 @@ bool PrebuildAllSchemas::Run(Deployer* d
   for (fs::directory_iterator iter(shared_data_path), end; iter != end;
        ++iter) {
     path entry(iter->path());
-    if (boost::ends_with(entry.filename().u8string(), ".schema.yaml")) {
+    if (boost::ends_with(entry.filename().string(), ".schema.yaml")) {
       the<DeploymentTask> t(new SchemaUpdate(entry));
       if (!t->Run(deployer))
         success = false;
@@ -483,7 +483,7 @@ bool SymlinkingPrebuiltDictionaries::Run
     if (fs::is_symlink(entry)) {
       try {
         // a symlink becomes dangling if the target file is no longer provided
-        std::error_code ec;
+	boost::system::error_code ec;
         auto target_path = fs::canonical(entry, ec);
         bool bad_link = bool(ec);
         bool linked_to_shared_data =
@@ -525,7 +525,7 @@ bool UserDictSync::Run(Deployer* deploye
 }
 
 static bool IsCustomizedCopy(const path& file_path) {
-  auto file_name = file_path.filename().u8string();
+  auto file_name = file_path.filename().string();
   if (boost::ends_with(file_name, ".yaml") &&
       !boost::ends_with(file_name, ".custom.yaml")) {
     Config config;
@@ -556,7 +556,7 @@ bool BackupConfigFiles::Run(Deployer* de
     path entry(iter->path());
     if (!fs::is_regular_file(entry))
       continue;
-    auto file_extension = entry.extension().u8string();
+    auto file_extension = entry.extension().string();
     bool is_yaml_file = file_extension == ".yaml";
     bool is_text_file = file_extension == ".txt";
     if (!is_yaml_file && !is_text_file)
@@ -570,8 +570,8 @@ bool BackupConfigFiles::Run(Deployer* de
       ++skipped;  // customized copy
       continue;
     }
-    std::error_code ec;
-    fs::copy_file(entry, backup, fs::copy_options::overwrite_existing, ec);
+    boost::system::error_code ec;
+    fs::copy_file(entry, backup, fs::copy_option::overwrite_if_exists, ec);
     if (ec) {
       LOG(ERROR) << "error backing up file " << backup;
       ++failure;
@@ -596,7 +596,7 @@ bool CleanupTrash::Run(Deployer* deploye
     path entry(iter->path());
     if (!fs::is_regular_file(entry))
       continue;
-    auto file_name = entry.filename().u8string();
+    auto file_name = entry.filename().string();
     if (file_name == "rime.log" || boost::ends_with(file_name, ".bin") ||
         boost::ends_with(file_name, ".reverse.kct") ||
         boost::ends_with(file_name, ".userdb.kct.old") ||
@@ -605,7 +605,7 @@ bool CleanupTrash::Run(Deployer* deploye
         return false;
       }
       path backup = trash / entry.filename();
-      std::error_code ec;
+      boost::system::error_code ec;
       fs::rename(entry, backup, ec);
       if (ec) {
         LOG(ERROR) << "error clean up file " << entry;
@@ -650,15 +650,15 @@ bool CleanOldLogFiles::Run(Deployer* dep
     try {
       // preparing files
       for (const auto& entry : fs::directory_iterator(dir)) {
-        const string& file_name(entry.path().filename().u8string());
-        if (entry.is_regular_file() && !entry.is_symlink() &&
+        const string& file_name(entry.path().filename().string());
+        if (fs::is_regular_file(entry.path()) && !fs::is_symlink(entry.path()) &&
             boost::starts_with(file_name, app_name) &&
             boost::ends_with(file_name, ".log") &&
             !boost::contains(file_name, today)) {
           files_to_remove.push_back(entry.path());
-        } else if (entry.is_symlink()) {
+        } else if (fs::is_symlink(entry.path())) {
           auto target = fs::read_symlink(entry.path());
-          const string& target_file_name(target.filename().u8string());
+          const string& target_file_name(target.filename().string());
           if (boost::starts_with(target_file_name, app_name) &&
               boost::ends_with(target_file_name, ".log")) {
             files_in_use.insert(target);
Index: librime-1.14.0/src/rime/lever/switcher_settings.cc
===================================================================
--- librime-1.14.0.orig/src/rime/lever/switcher_settings.cc
+++ librime-1.14.0/src/rime/lever/switcher_settings.cc
@@ -6,12 +6,12 @@
 //
 #include <utility>
 #include <boost/algorithm/string.hpp>
-#include <filesystem>
+#include <boost/filesystem.hpp>
 #include <rime/config.h>
 #include <rime/deployer.h>
 #include <rime/lever/switcher_settings.h>
 
-namespace fs = std::filesystem;
+namespace fs = boost::filesystem;
 
 namespace rime {
 
Index: librime-1.14.0/src/rime/lever/user_dict_manager.cc
===================================================================
--- librime-1.14.0.orig/src/rime/lever/user_dict_manager.cc
+++ librime-1.14.0/src/rime/lever/user_dict_manager.cc
@@ -6,7 +6,7 @@
 //
 #include <fstream>
 #include <boost/algorithm/string.hpp>
-#include <filesystem>
+#include <boost/filesystem.hpp>
 #include <boost/scope_exit.hpp>
 #include <rime/common.h>
 #include <rime/deployer.h>
@@ -16,7 +16,7 @@
 #include <rime/dict/user_db.h>
 #include <rime/lever/user_dict_manager.h>
 
-namespace fs = std::filesystem;
+namespace fs = boost::filesystem;
 
 namespace rime {
 
@@ -40,7 +40,7 @@ void UserDictManager::GetUserDictList(Us
     return;
   }
   for (fs::directory_iterator it(path_), end; it != end; ++it) {
-    string name = it->path().filename().u8string();
+    string name = it->path().filename().string();
     if (boost::ends_with(name, component->extension())) {
       boost::erase_last(name, component->extension());
       user_dict_list->push_back(name);
@@ -163,7 +163,7 @@ bool UserDictManager::UpgradeUserDict(co
   LOG(INFO) << "upgrading user dict '" << dict_name << "'.";
   path trash = deployer_->user_data_dir / "trash";
   if (!fs::exists(trash)) {
-    std::error_code ec;
+    boost::system::error_code ec;
     if (!fs::create_directories(trash, ec)) {
       LOG(ERROR) << "error creating directory '" << trash << "'.";
       return false;
@@ -180,7 +180,7 @@ bool UserDictManager::Synchronize(const
   bool success = true;
   path sync_dir(deployer_->sync_dir);
   if (!fs::exists(sync_dir)) {
-    std::error_code ec;
+    boost::system::error_code ec;
     if (!fs::create_directories(sync_dir, ec)) {
       LOG(ERROR) << "error creating directory '" << sync_dir << "'.";
       return false;
Index: librime-1.14.0/src/rime/resource.cc
===================================================================
--- librime-1.14.0.orig/src/rime/resource.cc
+++ librime-1.14.0/src/rime/resource.cc
@@ -4,13 +4,13 @@
 //
 
 #include <boost/algorithm/string.hpp>
-#include <filesystem>
+#include <boost/filesystem.hpp>
 #include <rime/resource.h>
 
 namespace rime {
 
 string ResourceResolver::ToResourceId(const string& file_path) const {
-  string string_path = path(file_path).generic_u8string();
+  string string_path = path(file_path).generic_string();
   bool has_prefix = boost::starts_with(string_path, type_.prefix);
   bool has_suffix = boost::ends_with(string_path, type_.suffix);
   size_t start = (has_prefix ? type_.prefix.length() : 0);
@@ -27,16 +27,16 @@ string ResourceResolver::ToFilePath(cons
 }
 
 path ResourceResolver::ResolvePath(const string& resource_id) {
-  return std::filesystem::absolute(root_path_ /
+  return boost::filesystem::absolute(root_path_ /
                                    (type_.prefix + resource_id + type_.suffix));
 }
 
 path FallbackResourceResolver::ResolvePath(const string& resource_id) {
   auto default_path = ResourceResolver::ResolvePath(resource_id);
-  if (!std::filesystem::exists(default_path)) {
-    auto fallback_path = std::filesystem::absolute(
+  if (!boost::filesystem::exists(default_path)) {
+    auto fallback_path = boost::filesystem::absolute(
         fallback_root_path_ / (type_.prefix + resource_id + type_.suffix));
-    if (std::filesystem::exists(fallback_path)) {
+    if (boost::filesystem::exists(fallback_path)) {
       return fallback_path;
     }
   }
Index: librime-1.14.0/test/resource_resolver_test.cc
===================================================================
--- librime-1.14.0.orig/test/resource_resolver_test.cc
+++ librime-1.14.0/test/resource_resolver_test.cc
@@ -1,9 +1,9 @@
 #include <fstream>
-#include <filesystem>
+#include <boost/filesystem.hpp>
 #include <gtest/gtest.h>
 #include <rime/resource.h>
 
-namespace fs = std::filesystem;
+namespace fs = boost::filesystem;
 using namespace rime;
 
 static const ResourceType kMineralsType = ResourceType{
Index: librime-1.14.0/tools/rime_table_decompiler.cc
===================================================================
--- librime-1.14.0.orig/tools/rime_table_decompiler.cc
+++ librime-1.14.0/tools/rime_table_decompiler.cc
@@ -122,7 +122,7 @@ int main(int argc, char* argv[]) {
   fout << "# Rime dictionary\n\n";
   fout << "---\n"
           "name: "
-       << file_path.stem().u8string()
+       << file_path.stem().string()
        << "\n"
           "version: \"1.0\"\n"
           "...\n\n";