Using std::error_code etc to replace boost's in /usr/local/Cellar/boost/1.54.0/include/boost/system/. You'll need to use an empty system_error.hpp and possibly specialize is_error_code_enum in namespace std::.

error_code.hpp

#pragma once
#include <system_error>
namespace boost { namespace system {
  using error_category = std::error_category;
  using error_code = std::error_code;
  using error_condition = std::error_condition;
  using system_error = std::system_error;
  using errc = std::errc;

  using std::system_category;
  using std::generic_category;

  template <class T> struct is_error_code_enum : public std::is_error_code_enum<T> {};
  template <class T> struct is_error_condition_enum : public std::is_error_condition_enum<T> {};

  using std::make_error_code;
  using std::make_error_condition;
}}