diff --git a/app/CMakeLists.txt b/app/CMakeLists.txt
index 1aa791dd4..bd4fc4bf1 100644
--- a/app/CMakeLists.txt
+++ b/app/CMakeLists.txt
@@ -1,7 +1,6 @@
-configure_file(poet.h.in poet.h)
 
-add_executable(poet poet.cpp)
-target_include_directories(poet PUBLIC "${CMAKE_CURRENT_BINARY_DIR}")
-target_link_libraries(poet PUBLIC poet_lib MPI::MPI_CXX)
+# add_executable(poet poet.cpp)
+# target_include_directories(poet PUBLIC "${CMAKE_CURRENT_BINARY_DIR}")
+# target_link_libraries(poet PUBLIC poet_lib MPI::MPI_CXX)
 
-install(TARGETS poet DESTINATION bin)
+# install(TARGETS poet DESTINATION bin)
diff --git a/app/poet.h.in b/app/poet.h.in
deleted file mode 100644
index 96a25a2c1..000000000
--- a/app/poet.h.in
+++ /dev/null
@@ -1,11 +0,0 @@
-#ifndef POET_H
-#define POET_H
-
-#include "poet/ChemistryModule.hpp"
-#include <Rcpp.h>
-const char *poet_version = "@POET_VERSION@";
-
-const char *CHEMISTRY_MODULE_NAME = "state_C";
-
-
-#endif // POET_H
diff --git a/src/Grid.cpp b/src/Base/Grid.cpp
similarity index 99%
rename from src/Grid.cpp
rename to src/Base/Grid.cpp
index 64561b5ae..e51b114ba 100644
--- a/src/Grid.cpp
+++ b/src/Base/Grid.cpp
@@ -18,7 +18,9 @@
 ** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */
 
-#include "poet/SimParams.hpp"
+#include "Grid.hpp"
+#include "SimParams.hpp"
+
 #include <RInside.h>
 #include <Rcpp.h>
 #include <algorithm>
@@ -26,7 +28,6 @@
 #include <cstdint>
 #include <new>
 #include <numeric>
-#include <poet/Grid.hpp>
 #include <stdexcept>
 #include <string>
 #include <vector>
diff --git a/include/poet/Grid.hpp b/src/Base/Grid.hpp
similarity index 99%
rename from include/poet/Grid.hpp
rename to src/Base/Grid.hpp
index 2ea2068b9..deec5c04a 100644
--- a/include/poet/Grid.hpp
+++ b/src/Base/Grid.hpp
@@ -21,7 +21,8 @@
 #ifndef GRID_H
 #define GRID_H
 
-#include "poet/SimParams.hpp"
+#include "SimParams.hpp"
+
 #include <RInside.h>
 #include <Rcpp.h>
 #include <array>
diff --git a/src/SimParams.cpp b/src/Base/SimParams.cpp
similarity index 99%
rename from src/SimParams.cpp
rename to src/Base/SimParams.cpp
index e02046392..f711e796a 100644
--- a/src/SimParams.cpp
+++ b/src/Base/SimParams.cpp
@@ -20,11 +20,13 @@
 ** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */
 
-#include "poet/enums.hpp"
+#include "SimParams.hpp"
+
+#include "../Chemistry/enums.hpp"
+
 #include <algorithm>
 #include <cassert>
 #include <cstdint>
-#include <poet/SimParams.hpp>
 
 #include <RInside.h>
 #include <Rcpp.h>
diff --git a/include/poet/SimParams.hpp b/src/Base/SimParams.hpp
similarity index 98%
rename from include/poet/SimParams.hpp
rename to src/Base/SimParams.hpp
index 9928bcdba..212ec9948 100644
--- a/include/poet/SimParams.hpp
+++ b/src/Base/SimParams.hpp
@@ -21,6 +21,12 @@
 #ifndef PARSER_H
 #define PARSER_H
 
+#include "../DataStructures/DataStructures.hpp"
+#include "../Macros.hpp"
+#include "../RInsidePOET.hpp"
+
+#include "argh.hpp" // Argument handler https://github.com/adishavit/argh
+
 #include <cstdint>
 #include <optional>
 #include <string>
@@ -28,10 +34,6 @@
 #include <unordered_map>
 #include <vector>
 
-#include "DataStructures.hpp"
-#include "Macros.hpp"
-#include "RInsidePOET.hpp"
-#include "argh.hpp" // Argument handler https://github.com/adishavit/argh
 #include <RInside.h>
 #include <Rcpp.h>
 // BSD-licenced
diff --git a/include/poet/argh.hpp b/src/Base/argh.hpp
similarity index 100%
rename from include/poet/argh.hpp
rename to src/Base/argh.hpp
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 74a61c8c7..addb7c11b 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -2,12 +2,19 @@ file(GLOB_RECURSE poet_lib_SRC
   CONFIGURE_DEPENDS
   "*.cpp" "*.c")
 
-add_library(poet_lib ${poet_lib_SRC})
-target_include_directories(poet_lib PUBLIC ${PROJECT_SOURCE_DIR}/include)
-target_link_libraries(poet_lib PUBLIC
-  MPI::MPI_CXX ${MATH_LIBRARY} RRuntime PhreeqcRM tug)
+configure_file(poet.h.in poet.h)
 
-target_compile_definitions(poet_lib PUBLIC STRICT_R_HEADERS OMPI_SKIP_MPICXX)
+add_executable(poet ${poet_lib_SRC})
+target_link_libraries(poet 
+  MPI::MPI_CXX 
+  ${MATH_LIBRARY} 
+  RRuntime 
+  PhreeqcRM 
+  tug
+)
+target_include_directories(poet PRIVATE "${CMAKE_CURRENT_BINARY_DIR}")
+
+target_compile_definitions(poet PRIVATE STRICT_R_HEADERS OMPI_SKIP_MPICXX)
 
 mark_as_advanced(PHREEQCRM_BUILD_MPI PHREEQCRM_DISABLE_OPENMP)
 set(PHREEQCRM_DISABLE_OPENMP ON CACHE BOOL "" FORCE)
@@ -15,11 +22,13 @@ set(PHREEQCRM_DISABLE_OPENMP ON CACHE BOOL "" FORCE)
 option(POET_DHT_DEBUG "Build with DHT debug info" OFF)
 
 if(POET_DHT_DEBUG)
-  target_compile_definitions(poet_lib PRIVATE DHT_STATISTICS)
+  target_compile_definitions(poet PRIVATE DHT_STATISTICS)
 endif()
 
 option(POET_PHT_ADDITIONAL_INFO "Enables additional information in the PHT" OFF)
 
 if (POET_PHT_ADDITIONAL_INFO)
-  target_compile_definitions(poet_lib PRIVATE POET_PHT_ADD)
+  target_compile_definitions(poet PRIVATE POET_PHT_ADD)
 endif()
+
+install(TARGETS poet DESTINATION bin)
\ No newline at end of file
diff --git a/src/ChemistryModule/ChemistryModule.cpp b/src/Chemistry/ChemistryModule.cpp
similarity index 99%
rename from src/ChemistryModule/ChemistryModule.cpp
rename to src/Chemistry/ChemistryModule.cpp
index a1b1a8837..46531f2c6 100644
--- a/src/ChemistryModule/ChemistryModule.cpp
+++ b/src/Chemistry/ChemistryModule.cpp
@@ -1,7 +1,9 @@
-#include "poet/ChemistryModule.hpp"
-#include "PhreeqcRM.h"
-#include "poet/DHT_Wrapper.hpp"
-#include "poet/Interpolation.hpp"
+#include "ChemistryModule.hpp"
+
+#include "SurrogateModels/DHT_Wrapper.hpp"
+#include "SurrogateModels/Interpolation.hpp"
+
+#include <PhreeqcRM.h>
 
 #include <algorithm>
 #include <cassert>
diff --git a/include/poet/ChemistryModule.hpp b/src/Chemistry/ChemistryModule.hpp
similarity index 98%
rename from include/poet/ChemistryModule.hpp
rename to src/Chemistry/ChemistryModule.hpp
index c0c7f9083..a17069d53 100644
--- a/include/poet/ChemistryModule.hpp
+++ b/src/Chemistry/ChemistryModule.hpp
@@ -3,12 +3,13 @@
 #ifndef CHEMISTRYMODULE_H_
 #define CHEMISTRYMODULE_H_
 
-#include "DHT_Wrapper.hpp"
-#include "DataStructures.hpp"
-#include "Interpolation.hpp"
-#include "IrmResult.h"
-#include "PhreeqcRM.h"
-#include "SimParams.hpp"
+#include "../Base/SimParams.hpp"
+#include "../DataStructures/DataStructures.hpp"
+#include "SurrogateModels/DHT_Wrapper.hpp"
+#include "SurrogateModels/Interpolation.hpp"
+
+#include <IrmResult.h>
+#include <PhreeqcRM.h>
 
 #include <array>
 #include <cstddef>
diff --git a/src/ChemistryModule/MasterFunctions.cpp b/src/Chemistry/MasterFunctions.cpp
similarity index 99%
rename from src/ChemistryModule/MasterFunctions.cpp
rename to src/Chemistry/MasterFunctions.cpp
index 51b656da3..543cd21a8 100644
--- a/src/ChemistryModule/MasterFunctions.cpp
+++ b/src/Chemistry/MasterFunctions.cpp
@@ -1,5 +1,6 @@
-#include "PhreeqcRM.h"
-#include "poet/ChemistryModule.hpp"
+#include "ChemistryModule.hpp"
+
+#include <PhreeqcRM.h>
 
 #include <algorithm>
 #include <cstddef>
diff --git a/src/ChemistryModule/SurrogateModels/CMakeLists.txt b/src/Chemistry/SurrogateModels/CMakeLists.txt
similarity index 100%
rename from src/ChemistryModule/SurrogateModels/CMakeLists.txt
rename to src/Chemistry/SurrogateModels/CMakeLists.txt
diff --git a/src/ChemistryModule/SurrogateModels/DHT.c b/src/Chemistry/SurrogateModels/DHT.c
similarity index 99%
rename from src/ChemistryModule/SurrogateModels/DHT.c
rename to src/Chemistry/SurrogateModels/DHT.c
index 0a7261049..b0d5b3caa 100644
--- a/src/ChemistryModule/SurrogateModels/DHT.c
+++ b/src/Chemistry/SurrogateModels/DHT.c
@@ -16,8 +16,9 @@
 ** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */
 
+#include "DHT.h"
+
 #include <mpi.h>
-#include <poet/DHT.h>
 
 #include <inttypes.h>
 #include <math.h>
diff --git a/include/poet/DHT.h b/src/Chemistry/SurrogateModels/DHT.h
similarity index 100%
rename from include/poet/DHT.h
rename to src/Chemistry/SurrogateModels/DHT.h
diff --git a/src/ChemistryModule/SurrogateModels/DHT_Wrapper.cpp b/src/Chemistry/SurrogateModels/DHT_Wrapper.cpp
similarity index 96%
rename from src/ChemistryModule/SurrogateModels/DHT_Wrapper.cpp
rename to src/Chemistry/SurrogateModels/DHT_Wrapper.cpp
index 861375c04..69491b2c2 100644
--- a/src/ChemistryModule/SurrogateModels/DHT_Wrapper.cpp
+++ b/src/Chemistry/SurrogateModels/DHT_Wrapper.cpp
@@ -20,14 +20,7 @@
 ** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */
 
-#include "poet/DHT_Wrapper.hpp"
-#include "poet/HashFunctions.hpp"
-#include "poet/Interpolation.hpp"
-#include "poet/LookupKey.hpp"
-#include "poet/Rounding.hpp"
-#include "poet/enums.hpp"
-
-#include "poet/RInsidePOET.hpp"
+#include "DHT_Wrapper.hpp"
 
 #include <algorithm>
 #include <cassert>
@@ -150,10 +143,9 @@ void DHT_Wrapper::fillDHT(const WorkPackage &work_package) {
       uint32_t proc, index;
       auto &key = dht_results.keys[i];
       const auto data =
-          (with_interp
-               ? outputToInputAndRates(work_package.input[i],
-                                       work_package.output[i])
-               : work_package.output[i]);
+          (with_interp ? outputToInputAndRates(work_package.input[i],
+                                               work_package.output[i])
+                       : work_package.output[i]);
       // void *data = (void *)&(work_package[i * this->data_count]);
       // fuzz data (round, logarithm etc.)
 
diff --git a/include/poet/DHT_Wrapper.hpp b/src/Chemistry/SurrogateModels/DHT_Wrapper.hpp
similarity index 97%
rename from include/poet/DHT_Wrapper.hpp
rename to src/Chemistry/SurrogateModels/DHT_Wrapper.hpp
index 115d5e769..083fe9d25 100644
--- a/include/poet/DHT_Wrapper.hpp
+++ b/src/Chemistry/SurrogateModels/DHT_Wrapper.hpp
@@ -23,14 +23,14 @@
 #ifndef DHT_WRAPPER_H
 #define DHT_WRAPPER_H
 
-#include "DataStructures.hpp"
+#include "../../Base/SimParams.hpp"
+#include "../../DataStructures/DataStructures.hpp"
+#include "../../RInsidePOET.hpp"
+#include "../enums.hpp"
+#include "HashFunctions.hpp"
 #include "LookupKey.hpp"
-#include "RInsidePOET.hpp"
-#include "SimParams.hpp"
-#include "enums.hpp"
-#include "poet/HashFunctions.hpp"
-#include "poet/LookupKey.hpp"
-#include "poet/Rounding.hpp"
+#include "Rounding.hpp"
+
 #include <array>
 #include <cstdint>
 #include <limits>
diff --git a/src/ChemistryModule/SurrogateModels/HashFunctions.cpp b/src/Chemistry/SurrogateModels/HashFunctions.cpp
similarity index 98%
rename from src/ChemistryModule/SurrogateModels/HashFunctions.cpp
rename to src/Chemistry/SurrogateModels/HashFunctions.cpp
index 431cd286f..d93702990 100644
--- a/src/ChemistryModule/SurrogateModels/HashFunctions.cpp
+++ b/src/Chemistry/SurrogateModels/HashFunctions.cpp
@@ -24,7 +24,7 @@
 ** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */
 
-#include "poet/HashFunctions.hpp"
+#include "HashFunctions.hpp"
 
 #if defined(_MSC_VER)
 
diff --git a/include/poet/HashFunctions.hpp b/src/Chemistry/SurrogateModels/HashFunctions.hpp
similarity index 100%
rename from include/poet/HashFunctions.hpp
rename to src/Chemistry/SurrogateModels/HashFunctions.hpp
diff --git a/include/poet/Interpolation.hpp b/src/Chemistry/SurrogateModels/Interpolation.hpp
similarity index 97%
rename from include/poet/Interpolation.hpp
rename to src/Chemistry/SurrogateModels/Interpolation.hpp
index 71b9f9a01..15361f4bf 100644
--- a/include/poet/Interpolation.hpp
+++ b/src/Chemistry/SurrogateModels/Interpolation.hpp
@@ -3,13 +3,12 @@
 #ifndef INTERPOLATION_H_
 #define INTERPOLATION_H_
 
-#include "DHT.h"
+#include "../../Base/SimParams.hpp"
+#include "../../DataStructures/DataStructures.hpp"
 #include "DHT_Wrapper.hpp"
-#include "DataStructures.hpp"
 #include "LookupKey.hpp"
-#include "poet/DHT_Wrapper.hpp"
-#include "poet/Rounding.hpp"
-#include "poet/SimParams.hpp"
+#include "Rounding.hpp"
+
 #include <cassert>
 #include <iostream>
 #include <list>
@@ -17,11 +16,11 @@
 #include <mpi.h>
 #include <string>
 #include <utility>
+
 extern "C" {
-#include "poet/DHT.h"
+#include "DHT.h"
 }
 
-#include "poet/LookupKey.hpp"
 #include <cstdint>
 #include <functional>
 #include <unordered_map>
diff --git a/src/ChemistryModule/SurrogateModels/InterpolationModule.cpp b/src/Chemistry/SurrogateModels/InterpolationModule.cpp
similarity index 94%
rename from src/ChemistryModule/SurrogateModels/InterpolationModule.cpp
rename to src/Chemistry/SurrogateModels/InterpolationModule.cpp
index 9384731b2..26bfd4ab0 100644
--- a/src/ChemistryModule/SurrogateModels/InterpolationModule.cpp
+++ b/src/Chemistry/SurrogateModels/InterpolationModule.cpp
@@ -1,13 +1,15 @@
 //  Time-stamp: "Last modified 2023-08-16 17:02:31 mluebke"
+#include "Interpolation.hpp"
 
-#include "poet/DHT_Wrapper.hpp"
-#include "poet/DataStructures.hpp"
-#include "poet/HashFunctions.hpp"
-#include "poet/Interpolation.hpp"
-#include "poet/LookupKey.hpp"
-#include "poet/Rounding.hpp"
-#include <Rcpp/vector/instantiation.h>
+#include "../../DataStructures/DataStructures.hpp"
+#include "DHT_Wrapper.hpp"
+#include "HashFunctions.hpp"
+#include "LookupKey.hpp"
+#include "Rounding.hpp"
+
+#include <Rcpp.h>
 #include <Rinternals.h>
+
 #include <algorithm>
 #include <array>
 #include <cassert>
@@ -20,8 +22,9 @@
 #include <string>
 #include <utility>
 #include <vector>
+
 extern "C" {
-#include "poet/DHT.h"
+#include "DHT.h"
 }
 
 namespace poet {
diff --git a/include/poet/LookupKey.hpp b/src/Chemistry/SurrogateModels/LookupKey.hpp
similarity index 97%
rename from include/poet/LookupKey.hpp
rename to src/Chemistry/SurrogateModels/LookupKey.hpp
index fbb064c53..f64b92721 100644
--- a/include/poet/LookupKey.hpp
+++ b/src/Chemistry/SurrogateModels/LookupKey.hpp
@@ -3,7 +3,8 @@
 #ifndef LOOKUPKEY_H_
 #define LOOKUPKEY_H_
 
-#include "poet/HashFunctions.hpp"
+#include "HashFunctions.hpp"
+
 #include <cstdint>
 #include <cstring>
 #include <vector>
diff --git a/src/ChemistryModule/SurrogateModels/ProximityHashTable.cpp b/src/Chemistry/SurrogateModels/ProximityHashTable.cpp
similarity index 97%
rename from src/ChemistryModule/SurrogateModels/ProximityHashTable.cpp
rename to src/Chemistry/SurrogateModels/ProximityHashTable.cpp
index 3ea44430d..f1589fa21 100644
--- a/src/ChemistryModule/SurrogateModels/ProximityHashTable.cpp
+++ b/src/Chemistry/SurrogateModels/ProximityHashTable.cpp
@@ -1,10 +1,11 @@
 //  Time-stamp: "Last modified 2023-08-15 14:50:59 mluebke"
+#include "Interpolation.hpp"
+
+#include "DHT_Wrapper.hpp"
+#include "HashFunctions.hpp"
+#include "LookupKey.hpp"
+#include "Rounding.hpp"
 
-#include "poet/DHT_Wrapper.hpp"
-#include "poet/HashFunctions.hpp"
-#include "poet/Interpolation.hpp"
-#include "poet/LookupKey.hpp"
-#include "poet/Rounding.hpp"
 #include <cassert>
 #include <cstddef>
 #include <cstdint>
@@ -12,8 +13,9 @@
 #include <memory>
 #include <unordered_set>
 #include <vector>
+
 extern "C" {
-#include "poet/DHT.h"
+#include "DHT.h"
 }
 
 namespace poet {
diff --git a/include/poet/Rounding.hpp b/src/Chemistry/SurrogateModels/Rounding.hpp
similarity index 100%
rename from include/poet/Rounding.hpp
rename to src/Chemistry/SurrogateModels/Rounding.hpp
diff --git a/src/ChemistryModule/WorkerFunctions.cpp b/src/Chemistry/WorkerFunctions.cpp
similarity index 98%
rename from src/ChemistryModule/WorkerFunctions.cpp
rename to src/Chemistry/WorkerFunctions.cpp
index 624a78b4f..faa99834b 100644
--- a/src/ChemistryModule/WorkerFunctions.cpp
+++ b/src/Chemistry/WorkerFunctions.cpp
@@ -1,8 +1,8 @@
 //  Time-stamp: "Last modified 2023-08-16 14:50:04 mluebke"
 
-#include "poet/ChemistryModule.hpp"
-#include "poet/DHT_Wrapper.hpp"
-#include "poet/Interpolation.hpp"
+#include "ChemistryModule.hpp"
+#include "SurrogateModels/DHT_Wrapper.hpp"
+#include "SurrogateModels/Interpolation.hpp"
 
 #include <IrmResult.h>
 #include <algorithm>
diff --git a/include/poet/enums.hpp b/src/Chemistry/enums.hpp
similarity index 100%
rename from include/poet/enums.hpp
rename to src/Chemistry/enums.hpp
diff --git a/include/poet/DataStructures.hpp b/src/DataStructures/DataStructures.hpp
similarity index 99%
rename from include/poet/DataStructures.hpp
rename to src/DataStructures/DataStructures.hpp
index 834ceca50..30f69e5dd 100644
--- a/include/poet/DataStructures.hpp
+++ b/src/DataStructures/DataStructures.hpp
@@ -1,7 +1,7 @@
 #ifndef DATASTRUCTURES_H_
 #define DATASTRUCTURES_H_
 
-#include "enums.hpp"
+#include "../Chemistry/enums.hpp"
 
 #include <Rcpp.h>
 
@@ -13,6 +13,7 @@
 #include <string>
 #include <utility>
 #include <vector>
+
 namespace poet {
 
 struct WorkPackage {
diff --git a/src/DataStructures/Field.cpp b/src/DataStructures/Field.cpp
index de364a599..71d51dea4 100644
--- a/src/DataStructures/Field.cpp
+++ b/src/DataStructures/Field.cpp
@@ -1,4 +1,5 @@
-#include "poet/DataStructures.hpp"
+#include "DataStructures.hpp"
+
 #include <Rcpp.h>
 #include <Rinternals.h>
 #include <cstddef>
diff --git a/include/poet/Macros.hpp b/src/Macros.hpp
similarity index 100%
rename from include/poet/Macros.hpp
rename to src/Macros.hpp
diff --git a/include/poet/RInsidePOET.hpp b/src/RInsidePOET.hpp
similarity index 100%
rename from include/poet/RInsidePOET.hpp
rename to src/RInsidePOET.hpp
diff --git a/src/DiffusionModule.cpp b/src/Transport/DiffusionModule.cpp
similarity index 96%
rename from src/DiffusionModule.cpp
rename to src/Transport/DiffusionModule.cpp
index ba7a60e62..b02f5ca0b 100644
--- a/src/DiffusionModule.cpp
+++ b/src/Transport/DiffusionModule.cpp
@@ -18,15 +18,15 @@
 ** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */
 
+#include "DiffusionModule.hpp"
+#include "../Macros.hpp"
+
+#include <tug/BoundaryCondition.hpp>
+#include <tug/Diffusion.hpp>
+
 #include <Rcpp.h>
 #include <algorithm>
 #include <cstdint>
-#include <poet/DiffusionModule.hpp>
-#include <poet/Grid.hpp>
-#include <poet/Macros.hpp>
-#include <poet/SimParams.hpp>
-#include <tug/BoundaryCondition.hpp>
-#include <tug/Diffusion.hpp>
 
 #include <array>
 #include <cassert>
@@ -177,11 +177,11 @@ void DiffusionModule::simulate(double dt) {
 
   t_field = field_2d;
 
-
   sim_a_transport = MPI_Wtime();
 
   transport_t += sim_a_transport - sim_b_transport;
-  std::cout << " done in "<< sim_a_transport - sim_b_transport << "sec" << std::endl;
+  std::cout << " done in " << sim_a_transport - sim_b_transport << "sec"
+            << std::endl;
 }
 
 void DiffusionModule::end() {
diff --git a/include/poet/DiffusionModule.hpp b/src/Transport/DiffusionModule.hpp
similarity index 96%
rename from include/poet/DiffusionModule.hpp
rename to src/Transport/DiffusionModule.hpp
index 8ea379027..a31bc0738 100644
--- a/include/poet/DiffusionModule.hpp
+++ b/src/Transport/DiffusionModule.hpp
@@ -21,16 +21,17 @@
 #ifndef DIFFUSION_MODULE_H
 #define DIFFUSION_MODULE_H
 
-#include "DataStructures.hpp"
-#include "SimParams.hpp"
-#include "poet/SimParams.hpp"
+#include "../Base/Grid.hpp"
+#include "../Base/SimParams.hpp"
+#include "../DataStructures/DataStructures.hpp"
+
+#include <tug/BoundaryCondition.hpp>
+#include <tug/Diffusion.hpp>
+
 #include <array>
 #include <cmath>
 #include <cstdint>
-#include <poet/Grid.hpp>
 #include <string>
-#include <tug/BoundaryCondition.hpp>
-#include <tug/Diffusion.hpp>
 #include <vector>
 
 namespace poet {
diff --git a/app/poet.cpp b/src/poet.cpp
similarity index 98%
rename from app/poet.cpp
rename to src/poet.cpp
index 4095cf858..aa6c22cb6 100644
--- a/app/poet.cpp
+++ b/src/poet.cpp
@@ -18,15 +18,18 @@
 ** Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */
 
+#include "Base/Grid.hpp"
+#include "Base/SimParams.hpp"
+#include "Chemistry/ChemistryModule.hpp"
+#include "Macros.hpp"
+#include "RInsidePOET.hpp"
+#include "Transport/DiffusionModule.hpp"
+
+#include <poet.h>
+
 #include <Rcpp.h>
 #include <cstdint>
 #include <cstdlib>
-#include <poet/ChemistryModule.hpp>
-#include <poet/DiffusionModule.hpp>
-#include <poet/Grid.hpp>
-#include <poet/Macros.hpp>
-#include <poet/RInsidePOET.hpp>
-#include <poet/SimParams.hpp>
 
 #include <cstring>
 #include <iostream>
@@ -34,7 +37,6 @@
 #include <vector>
 
 #include <mpi.h>
-#include <poet.h>
 
 using namespace std;
 using namespace poet;
diff --git a/src/poet.h.in b/src/poet.h.in
new file mode 100644
index 000000000..6a85179d4
--- /dev/null
+++ b/src/poet.h.in
@@ -0,0 +1,8 @@
+#ifndef POET_H
+#define POET_H
+
+static const char *poet_version = "@POET_VERSION@";
+
+static const char *CHEMISTRY_MODULE_NAME = "state_C";
+
+#endif // POET_H