diff --git a/Digitisers/SimpleDigi/src/TPCDigiAlg.cpp b/Digitisers/SimpleDigi/src/TPCDigiAlg.cpp
index 239048f42dceb887239b431dca12abf92a32e703..10247c12b2fc3a2c5b9ee3b0cd77a0560fce0cce 100644
--- a/Digitisers/SimpleDigi/src/TPCDigiAlg.cpp
+++ b/Digitisers/SimpleDigi/src/TPCDigiAlg.cpp
@@ -529,9 +529,9 @@ StatusCode TPCDigiAlg::execute()
   if (!STHcol) {
     return StatusCode::SUCCESS;
   }
-  auto SimTHit0 = STHcol->at(0);
+  // auto SimTHit0 = STHcol->at(0);
 
-  std::map< Voxel_tpc *, decltype(SimTHit0) > _tpcHitMap;
+  // std::map< Voxel_tpc *, decltype(SimTHit0) > _tpcHitMap;
   _tpcHitMap.clear();
 
   
diff --git a/Digitisers/SimpleDigi/src/TPCDigiAlg.h b/Digitisers/SimpleDigi/src/TPCDigiAlg.h
index c1c6eabd6c30335ac11c9d067d1f5bcdd56fa383..1eb97e9c508228eb3cf0ff9fc23e057c277840c1 100644
--- a/Digitisers/SimpleDigi/src/TPCDigiAlg.h
+++ b/Digitisers/SimpleDigi/src/TPCDigiAlg.h
@@ -29,6 +29,8 @@ Steve Aplin 26 June 2009 (DESY)
 
 #include <gsl/gsl_rng.h>
 
+#include <type_traits>
+
 //#ifdef MARLIN_USE_AIDA
 
 //#include <marlin/AIDAProcessor.h>
@@ -211,6 +213,7 @@ protected:
 
   std::vector< std::vector <Voxel_tpc *> > _tpcRowHits;
   // std::map< Voxel_tpc *,edm4hep::SimTrackerHit > _tpcHitMap;
+  std::map< Voxel_tpc *, edm4hep::ConstSimTrackerHit > _tpcHitMap;
 
   UTIL::BitField64* _cellid_encoder;
 
diff --git a/Generator/CMakeLists.txt b/Generator/CMakeLists.txt
index 0a244a3aa61afe39e9c8fa48ab7344a5866db4de..bf233d1b4b6ed3eed11735130ddd24ab09db84bf 100644
--- a/Generator/CMakeLists.txt
+++ b/Generator/CMakeLists.txt
@@ -27,6 +27,11 @@ gaudi_add_module(GenAlgo
                       ROOT::EG
 )
 
+target_include_directories(GenAlgo
+  PUBLIC ${LCIO_INCLUDE_DIRS}
+  PUBLIC ${HEPMC_INCLUDE_DIRS}
+)
+
 install(TARGETS GenAlgo
   EXPORT CEPCSWTargets
   RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}" COMPONENT bin