diff --git a/tdutils/CMakeLists.txt b/tdutils/CMakeLists.txt
index ce58be57d..3af31b35e 100644
--- a/tdutils/CMakeLists.txt
+++ b/tdutils/CMakeLists.txt
@@ -68,10 +68,12 @@ set(TDUTILS_SOURCE
   td/utils/HttpUrl.cpp
   td/utils/JsonBuilder.cpp
   td/utils/logging.cpp
+  td/utils/misc.cpp
   td/utils/MimeType.cpp
   td/utils/Random.cpp
   td/utils/StackAllocator.cpp
   td/utils/Status.cpp
+  td/utils/StringBuilder.cpp
   td/utils/Time.cpp
   td/utils/Timer.cpp
   td/utils/tl_parsers.cpp
@@ -162,10 +164,10 @@ set(TDUTILS_SOURCE
   td/utils/queue.h
   td/utils/Random.h
   td/utils/ScopeGuard.h
+  td/utils/SharedObjectPool.h
   td/utils/Slice-decl.h
   td/utils/Slice.h
   td/utils/SpinLock.h
-  td/utils/SharedObjectPool.h
   td/utils/StackAllocator.h
   td/utils/Status.h
   td/utils/Storer.h
diff --git a/tdutils/td/utils/StringBuilder.cpp b/tdutils/td/utils/StringBuilder.cpp
new file mode 100644
index 000000000..83fcb3c30
--- /dev/null
+++ b/tdutils/td/utils/StringBuilder.cpp
@@ -0,0 +1,108 @@
+//
+// 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 "td/utils/StringBuilder.h"
+
+#include <cstdio>
+
+namespace td {
+
+// TODO: optimize
+StringBuilder &StringBuilder::operator<<(int x) {
+  if (unlikely(end_ptr_ < current_ptr_)) {
+    return on_error();
+  }
+  current_ptr_ += std::snprintf(current_ptr_, reserved_size, "%d", x);
+  return *this;
+}
+
+StringBuilder &StringBuilder::operator<<(unsigned int x) {
+  if (unlikely(end_ptr_ < current_ptr_)) {
+    return on_error();
+  }
+  current_ptr_ += std::snprintf(current_ptr_, reserved_size, "%u", x);
+  return *this;
+}
+
+StringBuilder &StringBuilder::operator<<(long int x) {
+  if (unlikely(end_ptr_ < current_ptr_)) {
+    return on_error();
+  }
+  current_ptr_ += std::snprintf(current_ptr_, reserved_size, "%ld", x);
+  return *this;
+}
+
+StringBuilder &StringBuilder::operator<<(long unsigned int x) {
+  if (unlikely(end_ptr_ < current_ptr_)) {
+    return on_error();
+  }
+  current_ptr_ += std::snprintf(current_ptr_, reserved_size, "%lu", x);
+  return *this;
+}
+
+StringBuilder &StringBuilder::operator<<(long long int x) {
+  if (unlikely(end_ptr_ < current_ptr_)) {
+    return on_error();
+  }
+  current_ptr_ += std::snprintf(current_ptr_, reserved_size, "%lld", x);
+  return *this;
+}
+
+StringBuilder &StringBuilder::operator<<(long long unsigned int x) {
+  if (unlikely(end_ptr_ < current_ptr_)) {
+    return on_error();
+  }
+  current_ptr_ += std::snprintf(current_ptr_, reserved_size, "%llu", x);
+  return *this;
+}
+
+StringBuilder &StringBuilder::operator<<(double x) {
+  if (unlikely(end_ptr_ < current_ptr_)) {
+    return on_error();
+  }
+  auto left = end_ptr_ + reserved_size - current_ptr_;
+  int len = std::snprintf(current_ptr_, left, "%lf", x);
+  if (unlikely(len >= left)) {
+    error_flag_ = true;
+    current_ptr_ += left - 1;
+  } else {
+    current_ptr_ += len;
+  }
+  return *this;
+}
+
+StringBuilder &StringBuilder::operator<<(const void *ptr) {
+  if (unlikely(end_ptr_ < current_ptr_)) {
+    return on_error();
+  }
+  current_ptr_ += std::snprintf(current_ptr_, reserved_size, "%p", ptr);
+  return *this;
+}
+
+void StringBuilder::vprintf(const char *fmt, va_list list) {
+  if (unlikely(end_ptr_ < current_ptr_)) {
+    on_error();
+    return;
+  }
+
+  auto left = end_ptr_ + reserved_size - current_ptr_;
+  int len = std::vsnprintf(current_ptr_, left, fmt, list);
+  if (unlikely(len >= left)) {
+    error_flag_ = true;
+    current_ptr_ += left - 1;
+  } else {
+    current_ptr_ += len;
+  }
+}
+
+void StringBuilder::printf(const char *fmt, ...) {
+  va_list list;
+  va_start(list, fmt);
+  vprintf(fmt, list);
+  va_end(list);
+}
+
+}  // namespace td
diff --git a/tdutils/td/utils/StringBuilder.h b/tdutils/td/utils/StringBuilder.h
index 68b5c3c46..ca4144195 100644
--- a/tdutils/td/utils/StringBuilder.h
+++ b/tdutils/td/utils/StringBuilder.h
@@ -11,7 +11,6 @@
 #include "td/utils/StackAllocator.h"
 
 #include <cstdarg>
-#include <cstdio>
 #include <cstdlib>
 #include <cstring>
 #include <type_traits>
@@ -31,6 +30,7 @@ class StringBuilder {
     current_ptr_ = begin_ptr_;
     error_flag_ = false;
   }
+
   MutableCSlice as_cslice() {
     if (current_ptr_ >= end_ptr_ + reserved_size) {
       std::abort();  // shouldn't happen
@@ -82,101 +82,30 @@ class StringBuilder {
     return *this << static_cast<int>(c);
   }
 
-  // TODO: optimize
-  StringBuilder &operator<<(int x) {
-    if (unlikely(end_ptr_ < current_ptr_)) {
-      return on_error();
-    }
-    current_ptr_ += std::snprintf(current_ptr_, reserved_size, "%d", x);
-    return *this;
-  }
+  StringBuilder &operator<<(int x);
 
-  StringBuilder &operator<<(unsigned int x) {
-    if (unlikely(end_ptr_ < current_ptr_)) {
-      return on_error();
-    }
-    current_ptr_ += std::snprintf(current_ptr_, reserved_size, "%u", x);
-    return *this;
-  }
+  StringBuilder &operator<<(unsigned int x);
 
-  StringBuilder &operator<<(long int x) {
-    if (unlikely(end_ptr_ < current_ptr_)) {
-      return on_error();
-    }
-    current_ptr_ += std::snprintf(current_ptr_, reserved_size, "%ld", x);
-    return *this;
-  }
+  StringBuilder &operator<<(long int x);
 
-  StringBuilder &operator<<(long unsigned int x) {
-    if (unlikely(end_ptr_ < current_ptr_)) {
-      return on_error();
-    }
-    current_ptr_ += std::snprintf(current_ptr_, reserved_size, "%lu", x);
-    return *this;
-  }
+  StringBuilder &operator<<(long unsigned int x);
 
-  StringBuilder &operator<<(long long int x) {
-    if (unlikely(end_ptr_ < current_ptr_)) {
-      return on_error();
-    }
-    current_ptr_ += std::snprintf(current_ptr_, reserved_size, "%lld", x);
-    return *this;
-  }
+  StringBuilder &operator<<(long long int x);
 
-  StringBuilder &operator<<(long long unsigned int x) {
-    if (unlikely(end_ptr_ < current_ptr_)) {
-      return on_error();
-    }
-    current_ptr_ += std::snprintf(current_ptr_, reserved_size, "%llu", x);
-    return *this;
-  }
+  StringBuilder &operator<<(long long unsigned int x);
 
-  StringBuilder &operator<<(double x) {
-    if (unlikely(end_ptr_ < current_ptr_)) {
-      return on_error();
-    }
-    auto left = end_ptr_ + reserved_size - current_ptr_;
-    int len = std::snprintf(current_ptr_, left, "%lf", x);
-    if (unlikely(len >= left)) {
-      error_flag_ = true;
-      current_ptr_ += left - 1;
-    } else {
-      current_ptr_ += len;
-    }
-    return *this;
-  }
+  StringBuilder &operator<<(double x);
+
+  StringBuilder &operator<<(const void *ptr);
 
   template <class T>
   StringBuilder &operator<<(const T *ptr) {
-    if (unlikely(end_ptr_ < current_ptr_)) {
-      return on_error();
-    }
-    current_ptr_ += std::snprintf(current_ptr_, reserved_size, "%p", ptr);
-    return *this;
+    return *this << static_cast<const void *>(ptr);
   }
 
-  void vprintf(const char *fmt, va_list list) {
-    if (unlikely(end_ptr_ < current_ptr_)) {
-      on_error();
-      return;
-    }
+  void vprintf(const char *fmt, va_list list);
 
-    auto left = end_ptr_ + reserved_size - current_ptr_;
-    int len = std::vsnprintf(current_ptr_, left, fmt, list);
-    if (unlikely(len >= left)) {
-      error_flag_ = true;
-      current_ptr_ += left - 1;
-    } else {
-      current_ptr_ += len;
-    }
-  }
-
-  void printf(const char *fmt, ...) TD_ATTRIBUTE_FORMAT_PRINTF(2, 3) {
-    va_list list;
-    va_start(list, fmt);
-    vprintf(fmt, list);
-    va_end(list);
-  }
+  void printf(const char *fmt, ...) TD_ATTRIBUTE_FORMAT_PRINTF(2, 3);
 
  private:
   char *begin_ptr_;
diff --git a/tdutils/td/utils/misc.cpp b/tdutils/td/utils/misc.cpp
new file mode 100644
index 000000000..83db9da42
--- /dev/null
+++ b/tdutils/td/utils/misc.cpp
@@ -0,0 +1,63 @@
+//
+// 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 "td/utils/misc.h"
+
+#include <algorithm>
+#include <cstdlib>
+
+namespace td {
+
+char *str_dup(Slice str) {
+  char *res = static_cast<char *>(std::malloc(str.size() + 1));
+  if (res == nullptr) {
+    return nullptr;
+  }
+  std::copy(str.begin(), str.end(), res);
+  res[str.size()] = '\0';
+  return res;
+}
+
+string implode(vector<string> v, char delimiter) {
+  string result;
+  for (auto &str : v) {
+    if (!result.empty()) {
+      result += delimiter;
+    }
+    result += str;
+  }
+  return result;
+}
+
+string oneline(Slice str) {
+  string result;
+  result.reserve(str.size());
+  bool after_new_line = true;
+  for (auto c : str) {
+    if (c != '\n') {
+      if (after_new_line) {
+        if (c == ' ') {
+          continue;
+        }
+        after_new_line = false;
+      }
+      result += c;
+    } else {
+      after_new_line = true;
+      result += ' ';
+    }
+  }
+  while (!result.empty() && result.back() == ' ') {
+    result.pop_back();
+  }
+  return result;
+}
+
+double to_double(CSlice str) {
+  return std::atof(str.c_str());
+}
+
+}  // namespace td
diff --git a/tdutils/td/utils/misc.h b/tdutils/td/utils/misc.h
index 47ee51bfc..61003e144 100644
--- a/tdutils/td/utils/misc.h
+++ b/tdutils/td/utils/misc.h
@@ -12,8 +12,8 @@
 #include "td/utils/Status.h"
 #include "td/utils/StringBuilder.h"
 
+#include <algorithm>
 #include <cstdint>
-#include <cstdlib>
 #include <initializer_list>
 #include <iterator>
 #include <limits>
@@ -23,15 +23,7 @@
 
 namespace td {
 
-inline char *str_dup(Slice str) {
-  char *res = static_cast<char *>(std::malloc(str.size() + 1));
-  if (res == nullptr) {
-    return nullptr;
-  }
-  std::copy(str.begin(), str.end(), res);
-  res[str.size()] = '\0';
-  return res;
-}
+char *str_dup(Slice str);
 
 template <class T>
 std::pair<T, T> split(T s, char delimiter = ' ') {
@@ -54,16 +46,7 @@ vector<T> full_split(T s, char delimiter = ' ') {
   return result;
 }
 
-inline string implode(vector<string> v, char delimiter = ' ') {
-  string result;
-  for (auto &str : v) {
-    if (!result.empty()) {
-      result += delimiter;
-    }
-    result += str;
-  }
-  return result;
-}
+string implode(vector<string> v, char delimiter = ' ');
 
 namespace detail {
 
@@ -209,29 +192,7 @@ T trim(T str) {
   return T(begin, end);
 }
 
-inline string oneline(Slice str) {
-  string result;
-  result.reserve(str.size());
-  bool after_new_line = true;
-  for (auto c : str) {
-    if (c != '\n') {
-      if (after_new_line) {
-        if (c == ' ') {
-          continue;
-        }
-        after_new_line = false;
-      }
-      result += c;
-    } else {
-      after_new_line = true;
-      result += ' ';
-    }
-  }
-  while (!result.empty() && result.back() == ' ') {
-    result.pop_back();
-  }
-  return result;
-}
+string oneline(Slice str);
 
 template <class T>
 std::enable_if_t<std::is_signed<T>::value, T> to_integer(Slice str) {
@@ -303,9 +264,7 @@ typename std::enable_if<std::is_unsigned<T>::value, T>::type hex_to_integer(Slic
   return integer_value;
 }
 
-inline double to_double(CSlice str) {
-  return std::atof(str.c_str());
-}
+double to_double(CSlice str);
 
 template <class T>
 T clamp(T value, T min_value, T max_value) {