diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 93139c57f79afdb89980cda4b52a3149df96fd7c..ef1f04bee2f05dd6d2209721131922e7a7c2d546 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -4,11 +4,11 @@ slc6-gcc48:
   image: clicdp/slc6-base
   script:
     - export GCC_VERSION="4.8.5"
-    - export BUILD_TYPE="opt"
+    - export BUILD_TYPE="dbg"
     - source .gitlab-ci.d/init_x86_64.sh
     - mkdir build 
     - cd build
-    - cmake -GNinja -D DD4HEP_USE_GEANT4=ON -D DD4HEP_USE_BOOST=ON -DBoost_NO_BOOST_CMAKE=ON -D DD4HEP_USE_LCIO=ON -D BUILD_TESTING=ON  -D Geant4_DIR=$G4INSTALL/lib64/Geant4-10.2.2 -D DD4HEP_USE_CXX11=ON ..        
+    - cmake -GNinja -D DD4HEP_USE_GEANT4=ON -D DD4HEP_USE_BOOST=ON -DBoost_NO_BOOST_CMAKE=ON -D DD4HEP_USE_LCIO=ON -D BUILD_TESTING=ON  -D Geant4_DIR=$G4INSTALL/lib64/Geant4-10.2.2 -D DD4HEP_USE_CXX11=ON -DCMAKE_BUILD_TYPE=Debug ..        
     - ninja
     - ninja install
     - . ../bin/thisdd4hep.sh
@@ -30,11 +30,11 @@ slc6-gcc49:
   image: clicdp/slc6-base
   script:
     - export GCC_VERSION="4.9.3"
-    - export BUILD_TYPE="opt"
+    - export BUILD_TYPE="dbg"
     - source .gitlab-ci.d/init_x86_64.sh
     - mkdir build 
     - cd build
-    - cmake -GNinja -D DD4HEP_USE_GEANT4=ON -D DD4HEP_USE_BOOST=ON -DBoost_NO_BOOST_CMAKE=ON -D DD4HEP_USE_LCIO=ON -D BUILD_TESTING=ON -D Geant4_DIR=$G4INSTALL/lib64/Geant4-10.2.2 -D DD4HEP_USE_CXX11=ON ..        
+    - cmake -GNinja -D DD4HEP_USE_GEANT4=ON -D DD4HEP_USE_BOOST=ON -DBoost_NO_BOOST_CMAKE=ON -D DD4HEP_USE_LCIO=ON -D BUILD_TESTING=ON -D Geant4_DIR=$G4INSTALL/lib64/Geant4-10.2.2 -D DD4HEP_USE_CXX11=ON -DCMAKE_BUILD_TYPE=Debug ..        
     - ninja
     - ninja install
     - . ../bin/thisdd4hep.sh
@@ -56,11 +56,11 @@ centos7-gcc49:
   image: clicdp/cc7-base
   script:
     - export GCC_VERSION="4.9.3"
-    - export BUILD_TYPE="opt"
+    - export BUILD_TYPE="dbg"
     - source .gitlab-ci.d/init_x86_64.sh
     - mkdir build 
     - cd build
-    - cmake -GNinja -D DD4HEP_USE_GEANT4=ON -D DD4HEP_USE_BOOST=ON -DBoost_NO_BOOST_CMAKE=ON -D DD4HEP_USE_LCIO=ON -D BUILD_TESTING=ON -D Geant4_DIR=$G4INSTALL/lib64/Geant4-10.2.2 -D DD4HEP_USE_CXX11=ON ..        
+    - cmake -GNinja -D DD4HEP_USE_GEANT4=ON -D DD4HEP_USE_BOOST=ON -DBoost_NO_BOOST_CMAKE=ON -D DD4HEP_USE_LCIO=ON -D BUILD_TESTING=ON -D Geant4_DIR=$G4INSTALL/lib64/Geant4-10.2.2 -D DD4HEP_USE_CXX11=ON -DCMAKE_BUILD_TYPE=Debug ..        
     - ninja
     - ninja install
     - . ../bin/thisdd4hep.sh