diff --git a/src/md/MolecularDynamics.cpp b/src/md/MolecularDynamics.cpp
index 1883aca..2c9617f 100644
--- a/src/md/MolecularDynamics.cpp
+++ b/src/md/MolecularDynamics.cpp
@@ -7,4 +7,22 @@
  *
  * Copyright (c) 2023 jun <https://git.firmwarejun.net/jun/MolecularDynamics2>
  *
- */
\ No newline at end of file
+ */
+
+#include <vector>
+
+#include "Space.hpp"
+
+class MolecularDynamics {
+public:
+  explicit MolecularDynamics();
+  MolecularDynamics(double lattice, int numberOfCells, double temperature);
+
+private:
+  double m_lattice;
+  int m_numberOfCells;
+  double m_temperature;
+
+  Space m_space;
+  std::vector<Atom> m_atoms;
+};
\ No newline at end of file
diff --git a/src/md/mpi/Worker.hpp b/src/md/mpi/Worker.hpp
new file mode 100644
index 0000000..393009d
--- /dev/null
+++ b/src/md/mpi/Worker.hpp
@@ -0,0 +1,34 @@
+/**
+ * @file Worker.hpp
+ * @author Jun <jun@firmwarejun.net>
+ * @brief Worker declarations
+ * @version 0.1
+ * @date 2023-10-06
+ *
+ * Copyright (c) 2023 jun <https://git.firmwarejun.net/jun/MolecularDynamics2>
+ *
+ */
+
+#pragma once
+
+#include <boost/mpi.hpp>
+
+class Worker {
+public:
+  Worker(boost::mpi::communicator &comm) : m_comm(comm) {}
+
+  /**
+   * @brief Main worker loop
+   *
+   */
+  void work();
+
+private:
+  boost::mpi::communicator &m_comm;
+
+  /**
+   * @brief Compute forces between atoms
+   *
+   */
+  void computeForces();
+};