diff --git a/Makefile b/Makefile
index 492dfa5..a633bf4 100644
--- a/Makefile
+++ b/Makefile
@@ -6,3 +6,9 @@ build:
 
 install: build
 	meson install -C build
+
+check:
+	cppcheck --language=c++ --enable=all -q \
+		--suppress=missingInclude \
+		--suppress=missingIncludeSystem \
+		src
diff --git a/meson.build b/meson.build
index 18fc352..b7a72ed 100644
--- a/meson.build
+++ b/meson.build
@@ -20,6 +20,11 @@ executable(
   'mornelune',
   sources: [
     'src/main.cpp',
+
+    'src/Game.cpp',
+
+    'src/logs/Logs.cpp',
+    'src/logs/FileLogs.cpp',
   ],
   dependencies: [
   ],
diff --git a/src/Game.cpp b/src/Game.cpp
new file mode 100644
index 0000000..1dd6e0c
--- /dev/null
+++ b/src/Game.cpp
@@ -0,0 +1,23 @@
+#include "Game.hpp"
+
+namespace ml
+{
+  /*explicit*/ Game::Game(std::shared_ptr<Logs> logs)
+    : m_logs { logs }
+  {
+  }
+
+  /*virtual*/ Game::~Game()
+  {
+  }
+
+  void Game::start()
+  {
+    m_logs->log(LEVEL_DEBUG, "game started");
+  }
+
+  void Game::stop()
+  {
+    m_logs->log(LEVEL_DEBUG, "game stopped");
+  }
+}
diff --git a/src/Game.hpp b/src/Game.hpp
new file mode 100644
index 0000000..c77f89c
--- /dev/null
+++ b/src/Game.hpp
@@ -0,0 +1,26 @@
+#ifndef ml_GAME_HPP
+#define ml_GAME_HPP
+
+#include "commons.hpp"
+#include "logs/Logs.hpp"
+
+namespace ml
+{
+  /**
+   * Manage services and game state.
+   **/
+  class Game
+  {
+  public:
+    explicit Game(std::shared_ptr<Logs> logs);
+    virtual ~Game();
+
+    void start();
+    void stop();
+
+  private:
+    std::shared_ptr<Logs> m_logs;
+  };
+}
+
+#endif
diff --git a/src/commons.hpp b/src/commons.hpp
new file mode 100644
index 0000000..9c2383e
--- /dev/null
+++ b/src/commons.hpp
@@ -0,0 +1,24 @@
+#ifndef ml_COMMONS_HPP
+#define ml_COMMONS_HPP
+
+#include <stdexcept>
+#include <string>
+#include <cstring>
+#include <filesystem>
+#include <iostream>
+#include <fstream>
+
+#define ML_GEN_ENUM(X) X
+#define ML_GEN_STRING(X) #X
+
+#define ML_ENUM(PREFIX, KINDS)                                          \
+  enum PREFIX { KINDS(ML_GEN_ENUM)  };                                  \
+  constexpr char const* PREFIX ## Str [] = { KINDS(ML_GEN_STRING) }
+
+#define ML_ERROR(NAME)                                                  \
+  struct NAME : public std::runtime_error {                             \
+    explicit NAME (std::string const& what): std::runtime_error { what } \
+    {}                                                                  \
+  }
+
+#endif
diff --git a/src/logs/FileLogs.cpp b/src/logs/FileLogs.cpp
new file mode 100644
index 0000000..f0fad94
--- /dev/null
+++ b/src/logs/FileLogs.cpp
@@ -0,0 +1,19 @@
+#include "FileLogs.hpp"
+
+namespace ml
+{
+  /*explicit*/ FileLogs::FileLogs(std::filesystem::path const& path)
+    : Logs { m_file }
+  {
+    m_file.open(path, std::ios::app);
+
+    if (!m_file)
+      {
+        throw log_error {"cannot open log file '" + path.string() + "'"};
+      }
+  }
+
+  /*virtual*/ FileLogs::~FileLogs()
+  {
+  }
+}
diff --git a/src/logs/FileLogs.hpp b/src/logs/FileLogs.hpp
new file mode 100644
index 0000000..0b47416
--- /dev/null
+++ b/src/logs/FileLogs.hpp
@@ -0,0 +1,24 @@
+#ifndef ml_FILELOGS_HPP
+#define ml_FILELOGS_HPP
+
+#include "../commons.hpp"
+#include "Logs.hpp"
+
+namespace ml
+{
+  /**
+   * Logs game activities into a file.
+   * @see Logs
+   **/
+  class FileLogs: public Logs
+  {
+  public:
+    explicit FileLogs(std::filesystem::path const& path);
+    virtual ~FileLogs();
+
+  private:
+    std::ofstream m_file;
+  };
+}
+
+#endif
diff --git a/src/logs/Logs.cpp b/src/logs/Logs.cpp
new file mode 100644
index 0000000..afc58f2
--- /dev/null
+++ b/src/logs/Logs.cpp
@@ -0,0 +1,40 @@
+#include "Logs.hpp"
+
+namespace ml
+{
+  /*explicit*/ Logs::Logs(std::ostream& out)
+    : m_out { out }
+  {
+  }
+
+  /*virtual*/ Logs::~Logs()
+  {
+  }
+
+  void Logs::log(LogLevel level, std::string const& message)
+  {
+    std::string level_str = (LogLevelStr[level] + std::strlen("LEVEL_"));
+    auto now = std::chrono::system_clock::now();
+    std::time_t now_t = std::chrono::system_clock::to_time_t(now);
+
+    auto time_str = std::put_time(std::localtime(&now_t), "%F %T");
+
+    std::string color = "";
+
+    switch (level)
+      {
+      case LEVEL_DEBUG: color = "34"; break;
+
+      default:
+        throw log_error {std::string("cannot find color for log level '")
+                         + (LogLevelStr[level] + std::strlen("LEVEL_"))
+                         + "'"};
+      }
+
+    m_out
+      << time_str << " "
+      << ("\033[" + color + "m[" + level_str + "]\033[0m ")
+      << message
+      << "\n";
+  }
+}
diff --git a/src/logs/Logs.hpp b/src/logs/Logs.hpp
new file mode 100644
index 0000000..9ad59ef
--- /dev/null
+++ b/src/logs/Logs.hpp
@@ -0,0 +1,29 @@
+#ifndef ml_LOGS_HPP
+#define ml_LOGS_HPP
+
+#include "../commons.hpp"
+
+#define LOG_LEVELS(G) G(LEVEL_DEBUG)
+
+namespace ml
+{
+  ML_ENUM(LogLevel, LOG_LEVELS);
+  ML_ERROR(log_error);
+
+  /**
+   * Logs game activities into an output stream.
+   **/
+  class Logs
+  {
+  public:
+    explicit Logs(std::ostream& out);
+    virtual ~Logs();
+
+    void log(LogLevel level, std::string const& message);
+
+  private:
+    std::ostream& m_out;
+  };
+}
+
+#endif
diff --git a/src/main.cpp b/src/main.cpp
index 433956e..1ad5efd 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,8 +1,19 @@
+#include <filesystem>
 #include <iostream>
 #include "conf.hpp"
+#include "logs/FileLogs.hpp"
+
+#include "Game.hpp"
 
 int main(int, char**)
 {
-  std::cout << "Mornelune v" << ML_VERSION << std::endl;
+  auto logs = std::make_shared<ml::FileLogs>
+    (std::filesystem::temp_directory_path() / "mornelune.log");
+
+  ml::Game game {logs};
+
+  game.start();
+  game.stop();
+
   return 0;
 }