diff --git a/tdtl/CMakeLists.txt b/tdtl/CMakeLists.txt
index 9734bfbd..b0f83cd9 100644
--- a/tdtl/CMakeLists.txt
+++ b/tdtl/CMakeLists.txt
@@ -5,6 +5,7 @@ set(TDTL_SOURCE
   td/tl/tl_config.cpp
   td/tl/tl_core.cpp
   td/tl/tl_file_outputer.cpp
+  td/tl/tl_file_utils.cpp
   td/tl/tl_generate.cpp
   td/tl/tl_outputer.cpp
   td/tl/tl_string_outputer.cpp
@@ -13,6 +14,7 @@ set(TDTL_SOURCE
   td/tl/tl_config.h
   td/tl/tl_core.h
   td/tl/tl_file_outputer.h
+  td/tl/tl_file_utils.h
   td/tl/tl_generate.h
   td/tl/tl_outputer.h
   td/tl/tl_simple.h
diff --git a/tdtl/td/tl/tl_file_utils.cpp b/tdtl/td/tl/tl_file_utils.cpp
new file mode 100644
index 00000000..bc79d725
--- /dev/null
+++ b/tdtl/td/tl/tl_file_utils.cpp
@@ -0,0 +1,92 @@
+//
+// Copyright Aliaksei Levin (levlam@telegram.org), Arseny Smirnov (arseny30@gmail.com) 2014-2018
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+#include "tl_file_utils.h"
+
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+
+namespace td {
+namespace tl {
+
+std::string get_file_contents(const std::string &file_name, const std::string &mode) {
+  FILE *f = std::fopen(file_name.c_str(), mode.c_str());
+  if (f == NULL) {
+    return std::string();
+  }
+
+  int fseek_res = std::fseek(f, 0, SEEK_END);
+  if (fseek_res != 0) {
+    std::fprintf(stderr, "Can't seek to the end of the file \"%s\"", file_name.c_str());
+    std::abort();
+  }
+  long size_long = std::ftell(f);
+  if (size_long < 0 || size_long >= (1 << 25)) {
+    std::fprintf(stderr, "Wrong file \"%s\" has wrong size = %ld", file_name.c_str(), size_long);
+    std::abort();
+  }
+  std::size_t size = static_cast<std::size_t>(size_long);
+
+  std::string result(size, ' ');
+  std::rewind(f);
+  std::size_t fread_res = std::fread(&result[0], size, 1, f);
+  if (size != 0 && fread_res != 1) {
+    std::fprintf(stderr, "Can't read file \"%s\"", file_name.c_str());
+    std::abort();
+  }
+  std::fclose(f);
+
+  return result;
+}
+
+bool put_file_contents(const std::string &file_name, const std::string &mode, const std::string &contents) {
+  FILE *f = std::fopen(file_name.c_str(), mode.c_str());
+  if (f == NULL) {
+    std::fprintf(stderr, "Can't open file \"%s\"\n", file_name.c_str());
+    return false;
+  }
+
+  std::size_t fwrite_res = std::fwrite(contents.c_str(), contents.size(), 1, f);
+  if (fwrite_res != 1) {
+    std::fclose(f);
+    return false;
+  }
+  if (std::fclose(f) != 0) {
+    return false;
+  }
+  return true;
+}
+
+std::string remove_documentation(const std::string &str) {
+  std::size_t line_begin = 0;
+  std::string result;
+  bool inside_documentation = false;
+  while (line_begin < str.size()) {
+    std::size_t line_end = str.find('\n', line_begin);
+    if (line_end == std::string::npos) {
+      line_end = str.size() - 1;
+    }
+    std::string line = str.substr(line_begin, line_end - line_begin + 1);
+    line_begin = line_end + 1;
+
+    std::size_t pos = line.find_first_not_of(' ');
+    if (pos != std::string::npos && ((line[pos] == '/' && line[pos + 1] == '/' && line[pos + 2] == '/') ||
+                                     (line[pos] == '/' && line[pos + 1] == '*' && line[pos + 2] == '*') ||
+                                     (inside_documentation && line[pos] == '*'))) {
+      inside_documentation = !(line[pos] == '/' && line[pos + 1] == '/' && line[pos + 2] == '/') &&
+                             !(line[pos] == '*' && line[pos + 1] == '/');
+      continue;
+    }
+
+    inside_documentation = false;
+    result += line;
+  }
+  return result;
+}
+
+}  // namespace tl
+}  // namespace td
diff --git a/tdtl/td/tl/tl_file_utils.h b/tdtl/td/tl/tl_file_utils.h
new file mode 100644
index 00000000..50e40b44
--- /dev/null
+++ b/tdtl/td/tl/tl_file_utils.h
@@ -0,0 +1,21 @@
+//
+// Copyright Aliaksei Levin (levlam@telegram.org), Arseny Smirnov (arseny30@gmail.com) 2014-2018
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+#pragma once
+
+#include <string>
+
+namespace td {
+namespace tl {
+
+std::string get_file_contents(const std::string &file_name, const std::string &mode);
+
+bool put_file_contents(const std::string &file_name, const std::string &mode, const std::string &contents);
+
+std::string remove_documentation(const std::string &str);
+
+}  // namespace tl
+}  // namespace td
diff --git a/tdtl/td/tl/tl_generate.cpp b/tdtl/td/tl/tl_generate.cpp
index cb00cc11..401d451c 100644
--- a/tdtl/td/tl/tl_generate.cpp
+++ b/tdtl/td/tl/tl_generate.cpp
@@ -8,6 +8,7 @@
 
 #include "tl_config.h"
 #include "tl_core.h"
+#include "tl_file_utils.h"
 #include "tl_outputer.h"
 #include "tl_string_outputer.h"
 #include "tl_writer.h"
@@ -805,81 +806,6 @@ void write_tl(const tl_config &config, tl_outputer &out, const TL_writer &w) {
   }
 }
 
-static std::string get_file_contents(const std::string &file_name, const std::string &mode) {
-  FILE *f = std::fopen(file_name.c_str(), mode.c_str());
-  if (f == NULL) {
-    return std::string();
-  }
-
-  int fseek_res = std::fseek(f, 0, SEEK_END);
-  if (fseek_res != 0) {
-    std::fprintf(stderr, "Can't seek to the end of the file \"%s\"", file_name.c_str());
-    std::abort();
-  }
-  long size_long = std::ftell(f);
-  if (size_long < 0 || size_long >= (1 << 25)) {
-    std::fprintf(stderr, "Wrong file \"%s\" has wrong size = %ld", file_name.c_str(), size_long);
-    std::abort();
-  }
-  std::size_t size = static_cast<std::size_t>(size_long);
-
-  std::string result(size, ' ');
-  std::rewind(f);
-  std::size_t fread_res = std::fread(&result[0], size, 1, f);
-  if (size != 0 && fread_res != 1) {
-    std::fprintf(stderr, "Can't read file \"%s\"", file_name.c_str());
-    std::abort();
-  }
-  std::fclose(f);
-
-  return result;
-}
-
-static bool put_file_contents(const std::string &file_name, const std::string &mode, const std::string &contents) {
-  FILE *f = std::fopen(file_name.c_str(), mode.c_str());
-  if (f == NULL) {
-    std::fprintf(stderr, "Can't open file \"%s\"\n", file_name.c_str());
-    return false;
-  }
-
-  std::size_t fwrite_res = std::fwrite(contents.c_str(), contents.size(), 1, f);
-  if (fwrite_res != 1) {
-    std::fclose(f);
-    return false;
-  }
-  if (std::fclose(f) != 0) {
-    return false;
-  }
-  return true;
-}
-
-static std::string remove_documentation(const std::string &str) {
-  std::size_t line_begin = 0;
-  std::string result;
-  bool inside_documentation = false;
-  while (line_begin < str.size()) {
-    std::size_t line_end = str.find('\n', line_begin);
-    if (line_end == std::string::npos) {
-      line_end = str.size() - 1;
-    }
-    std::string line = str.substr(line_begin, line_end - line_begin + 1);
-    line_begin = line_end + 1;
-
-    std::size_t pos = line.find_first_not_of(' ');
-    if (pos != std::string::npos && ((line[pos] == '/' && line[pos + 1] == '/' && line[pos + 2] == '/') ||
-                                     (line[pos] == '/' && line[pos + 1] == '*' && line[pos + 2] == '*') ||
-                                     (inside_documentation && line[pos] == '*'))) {
-      inside_documentation = !(line[pos] == '/' && line[pos + 1] == '/' && line[pos + 2] == '/') &&
-                             !(line[pos] == '*' && line[pos + 1] == '/');
-      continue;
-    }
-
-    inside_documentation = false;
-    result += line;
-  }
-  return result;
-}
-
 tl_config read_tl_config_from_file(const std::string &file_name) {
   std::string config = get_file_contents(file_name, "rb");
   if (config.empty()) {