diff --git a/src/opt/mpi/include/mpi_wrappers.cc.h b/src/opt/mpi/include/mpi_wrappers.cc.h
new file mode 100644
index 0000000..5979385
--- /dev/null
+++ b/src/opt/mpi/include/mpi_wrappers.cc.h
@@ -0,0 +1,106 @@
+// -*- C++ -*-
+/**
+
+   @file opt/mpi/include/mpi_wrappers.cc.h
+   @brief MPI wrapper template implementations.
+
+   Copyright (c) 2024 Christian Zimmermann. All rights reserved.
+   Mail: chizeta@f3l.de
+   
+**/
+
+#ifndef __cxz_mpi_wrappers_cc_h__
+#define __cxz_mpi_wrappers_cc_h__
+
+#include "mpi_wrappers.h"
+
+namespace CNORXZ
+{
+    namespace mpi
+    {
+	
+	template <typename T>
+	void BCast<T>::bcast(T& d, SizeT root)
+	{
+	    static_assert( TypeMap<T>::exists, "no bcast implementation for given type" );
+	    const int ret = MPI_Bcast( reinterpret_cast<void*>(&d), 1,
+				       TypeMap<T>::value, MPI_COMM_WORLD );
+	    CXZ_ASSERT(ret == MPI_SUCCESS, "got bcast error = " << ret);
+	    return;
+	}
+
+	// preliminary solutions, use cereal serialization in the future!!!
+	template <typename T>
+	void BCast<Vector<T>>::bcast(Vector<T>& d, SizeT root)
+	{
+	    SizeT size = d.size();
+	    const int ret = MPI_Bcast( reinterpret_cast<void*>(&size), 1,
+				       MPI_UNSIGNED_LONG, MPI_COMM_WORLD );
+	    CXZ_ASSERT(ret == MPI_SUCCESS, "got bcast error = " << ret);
+	    if(size != d.size()){
+		d.resize(size);
+	    }
+	    if constexpr( BCast<T>::special ){
+		for(auto& x: d){
+		    bcast(x, root);
+		}
+	    }
+	    else {
+		const int ret2 = MPI_Bcast( reinterpret_cast<void*>(d.data()), size,
+					    TypeMap<T>::value, MPI_COMM_WORLD );
+		CXZ_ASSERT(ret2 == MPI_SUCCESS, "got bcast error = " << ret2);
+	    }
+	}
+
+	template <typename T, SizeT N>
+	void BCast<Arr<T,N>>::bcast(Arr<T,N>& d, SizeT root)
+	{
+	    if constexpr( BCast<T,N>::special ){
+		for(auto& x: d){
+		    bcast(x, root);
+		}
+	    }
+	    else {
+		const int ret = MPI_Bcast( reinterpret_cast<void*>(d.data()), N,
+					   TypeMap<T>::value, MPI_COMM_WORLD );
+		CXZ_ASSERT(ret == MPI_SUCCESS, "got bcast error = " << ret2);
+	    }
+	}
+
+	inline void BCast<String>::bcast(String& d, SizeT root)
+	{
+	    SizeT size = d.size();
+	    const int ret = MPI_Bcast( reinterpret_cast<void*>(&size), 1,
+				       MPI_UNSIGNED_LONG, MPI_COMM_WORLD );
+	    CXZ_ASSERT(ret == MPI_SUCCESS, "got bcast error = " << ret);
+	    if(size != d.size()){
+		d.resize(size);
+	    }
+	    const int ret = MPI_Bcast( reinterpret_cast<void*>(d.data()), size,
+				       MPI_CHAR, MPI_COMM_WORLD );
+	    CXZ_ASSERT(ret == MPI_SUCCESS, "got bcast error = " << ret);
+	}
+
+	template <typename... Ts>
+	void BCast<Tuple<Ts...>>::bcast(Tuple<Ts...>& d, SizeT root)
+	{
+	    if constexpr( ( BCast<Ts>::special or ... ) ){
+		ifor<0,sizeof...(Ts)>( [&](auto i) { bcast( std::get<i>(d), root ); }, NoF {} );
+	    }
+	    else {
+		const int ret = MPI_Bcast( reinterpret_cast<void*>(&d), sizeof(d),
+					   MPI_BYTE, MPI_COMM_WORLD );
+		CXZ_ASSERT(ret == MPI_SUCCESS, "got bcast error = " << ret);
+	    }
+	}
+
+	template <typename T>
+	void bcast(T& d, SizeT root)
+	{
+	    return BCast<T>(d, root);
+	}
+	
+    } // namespace mpi
+} // namespace CNORXZ
+
+#endif
diff --git a/src/opt/mpi/include/mpi_wrappers.h b/src/opt/mpi/include/mpi_wrappers.h
new file mode 100644
index 0000000..caee97b
--- /dev/null
+++ b/src/opt/mpi/include/mpi_wrappers.h
@@ -0,0 +1,66 @@
+// -*- C++ -*-
+/**
+
+   @file opt/mpi/include/mpi_wrappers.h
+   @brief MPI wrapper template delarations.
+
+   Copyright (c) 2024 Christian Zimmermann. All rights reserved.
+   Mail: chizeta@f3l.de
+   
+**/
+
+#ifndef __cxz_mpi_wrappers_h__
+#define __cxz_mpi_wrappers_h__
+
+#include "mpi.h"
+#include "cnorxz.h"
+#include "typemap.h"
+
+namespace CNORXZ
+{
+    namespace mpi
+    {
+	
+	template <typename T>
+	struct BCast
+	{
+	    static constexpr bool special = false;
+	    static void bcast(T& d, SizeT root);
+	};
+
+	template <typename T>
+	struct BCast<Vector<T>>
+	{
+	    static constexpr bool special = true;
+	    static void bcast(Vector<T>& d, SizeT root);
+	};
+
+	template <typename T, SizeT N>
+	struct BCast<Arr<T,N>>
+	{
+	    static constexpr bool special = true;
+	    static void bcast(Arr<T,N>& d, SizeT root);
+	};
+
+	template <>
+	struct BCast<String>
+	{
+	    static constexpr bool special = true;
+	    static inline void bcast(String& d, SizeT root);
+	};
+
+	template <typename... Ts>
+	struct BCast<Tuple<Ts...>>
+	{
+	    static constexpr bool special = true;
+	    static void bcast(Tuple<Ts...>& d, SizeT root);
+	};
+
+	template <typename T>
+	void bcast(T& d, SizeT root);
+
+
+    } // namespace mpi
+} // namespace CNORXZ
+
+#endif
diff --git a/src/opt/mpi/include/rrange.cc.h b/src/opt/mpi/include/rrange.cc.h
index e2663d4..50a815c 100644
--- a/src/opt/mpi/include/rrange.cc.h
+++ b/src/opt/mpi/include/rrange.cc.h
@@ -13,6 +13,7 @@
 #define __cxz_mpi_rrange_cc_h__
 
 #include "rrange.h"
+#include "mpi_wrappers.h"
 
 namespace CNORXZ
 {
diff --git a/src/opt/mpi/include/rrange.h b/src/opt/mpi/include/rrange.h
index 8503ccf..03ebae3 100644
--- a/src/opt/mpi/include/rrange.h
+++ b/src/opt/mpi/include/rrange.h
@@ -35,7 +35,6 @@ namespace CNORXZ
 
 	    INDEX_RANDOM_ACCESS_ITERATOR_DEFS(MetaType);
 
-	    // constructors!!!
 	    /** Default constructor. */
 	    RIndex() = default;
 
diff --git a/src/opt/mpi/include/typemap.h b/src/opt/mpi/include/typemap.h
new file mode 100644
index 0000000..b0e20c9
--- /dev/null
+++ b/src/opt/mpi/include/typemap.h
@@ -0,0 +1,64 @@
+
+#ifndef __cxz_mpi_typemap_h__
+#define __cxz_mpi_typemap_h__
+
+#include "mpi.h"
+
+namespace CNORXZ
+{
+    namespace mpi
+    {
+	template <typename T>
+	struct Typemap
+	{
+	    static constexpr bool exists = false;
+	};
+
+	template <>
+	struct Typemap<int>
+	{
+	    static constexpr bool exists = true;
+	    static constexpr MPI_Datatype value = MPI_INT;
+	};
+
+	template <>
+	struct Typemap<unsigned>
+	{
+	    static constexpr bool exists = true;
+	    static constexpr MPI_Datatype value = MPI_UNSIGNED;
+	};
+
+	template <>
+	struct Typemap<long int>
+	{
+	    static constexpr bool exists = true;
+	    static constexpr MPI_Datatype value = MPI_LONG;
+	};
+
+	template <>
+	struct Typemap<unsigned long>
+	{
+	    static constexpr bool exists = true;
+	    static constexpr MPI_Datatype value = MPI_UNSIGNED_LONG;
+	};
+
+	template <>
+	struct Typemap<double>
+	{
+	    static constexpr bool exists = true;
+	    static constexpr MPI_Datatype value = MPI_DOUBLE;
+	};
+
+	template <>
+	struct Typemap<float>
+	{
+	    static constexpr bool exists = true;
+	    static constexpr MPI_Datatype value = MPI_FLOAT;
+	};
+
+	// further !!!
+	
+    } // namespace mpi
+} // namespace CNORXZ
+
+#endif