diff --git a/g3log/filesink.cpp b/g3log/filesink.cpp
new file mode 100644
index 0000000..bfe8d5c
--- /dev/null
+++ b/g3log/filesink.cpp
@@ -0,0 +1,92 @@
+/** ==========================================================================
+ * 2013 by KjellKod.cc. This is PUBLIC DOMAIN to use at your own risk and comes
+ * with no warranties. This code is yours to share, use and modify with no
+ * strings attached and no restrictions or obligations.
+ *
+ * For more information see g3log/LICENSE or refer refer to http://unlicense.org
+ * ============================================================================*/
+
+#include "g3log/filesink.hpp"
+#include "filesinkhelper.ipp"
+#include <cassert>
+
+namespace g3 {
+   using namespace internal;
+
+
+   FileSink::FileSink(const std::string &log_prefix, const std::string &log_directory, const std::string& logger_id)
+      : _log_file_with_path(log_directory)
+      , _log_prefix_backup(log_prefix)
+      , _outptr(new std::ofstream)
+   {
+      _log_prefix_backup = prefixSanityFix(log_prefix);
+      if (!isValidFilename(_log_prefix_backup)) {
+         std::cerr << "g3log: forced abort due to illegal log prefix [" << log_prefix << "]" << std::endl;
+         abort();
+      }
+
+      std::string file_name = createLogFileName(_log_prefix_backup, logger_id);
+      _log_file_with_path = pathSanityFix(_log_file_with_path, file_name);
+      _outptr = createLogFile(_log_file_with_path);
+
+      if (!_outptr) {
+         std::cerr << "Cannot write log file to location, attempting current directory" << std::endl;
+         _log_file_with_path = "./" + file_name;
+         _outptr = createLogFile(_log_file_with_path);
+      }
+      assert(_outptr && "cannot open log file at startup");
+      addLogFileHeader();
+   }
+
+
+   FileSink::~FileSink() {
+      std::string exit_msg {"g3log g3FileSink shutdown at: "};
+      exit_msg.append(localtime_formatted(systemtime_now(), internal::time_formatted)).append({"\n"});
+      filestream() << exit_msg << std::flush;
+
+      exit_msg.append({"Log file at: ["}).append(_log_file_with_path).append({"]\n"});
+      std::cerr << exit_msg << std::flush;
+   }
+
+   // The actual log receiving function
+   void FileSink::fileWrite(LogMessageMover message) {
+      std::ofstream &out(filestream());
+      out << message.get().toString() << std::flush;
+   }
+
+   std::string FileSink::changeLogFile(const std::string &directory, const std::string &logger_id) {
+
+      auto now = g3::systemtime_now();
+      auto now_formatted = g3::localtime_formatted(now, {internal::date_formatted + " " + internal::time_formatted});
+
+      std::string file_name = createLogFileName(_log_prefix_backup, logger_id);
+      std::string prospect_log = directory + file_name;
+      std::unique_ptr<std::ofstream> log_stream = createLogFile(prospect_log);
+      if (nullptr == log_stream) {
+         filestream() << "\n" << now_formatted << " Unable to change log file. Illegal filename or busy? Unsuccessful log name was: " << prospect_log;
+         return {}; // no success
+      }
+
+      addLogFileHeader();
+      std::ostringstream ss_change;
+      ss_change << "\n\tChanging log file from : " << _log_file_with_path;
+      ss_change << "\n\tto new location: " << prospect_log << "\n";
+      filestream() << now_formatted << ss_change.str();
+      ss_change.str("");
+
+      std::string old_log = _log_file_with_path;
+      _log_file_with_path = prospect_log;
+      _outptr = std::move(log_stream);
+      ss_change << "\n\tNew log file. The previous log file was at: ";
+      ss_change << old_log;
+      filestream() << now_formatted << ss_change.str();
+      return _log_file_with_path;
+   }
+   std::string FileSink::fileName() {
+      return _log_file_with_path;
+   }
+   void FileSink::addLogFileHeader() {
+      filestream() << header();
+   }
+
+} // g3