diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 32f5564b5637798468d993b5c56d359cde6392eb..c16df5b1b002e18e6d5536b11e5504422e429396 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,4 +1,4 @@
-image: eicweb.phy.anl.gov:4567/containers/eic_container/eic_container:latest 
+image: eicweb.phy.anl.gov:4567/eic/npdet/npdet:latest 
 
 default:
   artifacts:
@@ -11,9 +11,9 @@ default:
         #      - .git/
         #      - datasets/.git/
   before_script:
-    - git clone https://eicweb.phy.anl.gov/EIC/NPDet.git && mkdir NPDet/build
-    - cd NPDet/build && cmake ../. -DCMAKE_INSTALL_PREFIX=/usr/local && make -j10 && make install
-    - cd ../.. 
+    - git clone https://eicweb.phy.anl.gov/EIC/NPDet.git
+        #    - cd NPDet/build && cmake ../. -DCMAKE_INSTALL_PREFIX=/usr/local && make -j10 && make install
+        #    - cd ../.. 
 
 stages:
   - data_init
@@ -49,6 +49,15 @@ cal_sim_1_dummy_test2:
   script:
     - echo "here we run simulation"
 
+roman_pot_simu:
+  stage: simulate
+  tags:
+    - sodium
+  script:
+    - cp NPDet/src/GenericDetectors/trackers/compact/elements.xml ./.
+    - cp NPDet/src/GenericDetectors/trackers/compact/materials.xml ./.
+    - bash trackers/roman_pot_simu.sh
+
 cal_test_1_dummy_test2:
   stage: benchmarks
   tags:
@@ -89,21 +98,11 @@ track_test_1_dummy_test:
     - bash trackers/dummy_test.sh
   allow_failure: true
 
-roman_pot_simu:
-  stage: simulate
-  tags:
-    - sodium
-  script:
-    - bash trackers/roman_pot_simu.sh
-  allow_failure: true
-
 roman_pot_nhits:
   stage: benchmarks
   tags:
     - sodium
   script:
-    - cp NPDet/src/GenericDetectors/trackers/compact/elements.xml trackers/.
-    - cp NPDet/src/GenericDetectors/trackers/compact/materials.xml trackers/.
     - root -b -q trackers/simple_tracking.cxx+
   allow_failure: true
 
diff --git a/trackers/roman_pot.xml b/trackers/roman_pot.xml
index f16715918ffd4849ea68ffc900a652fd8f4a9741..0174a5020189542682b53ef7fcf206c73156de02 100644
--- a/trackers/roman_pot.xml
+++ b/trackers/roman_pot.xml
@@ -68,9 +68,8 @@
       <frame x = "20.0*cm" y = "10.0*cm" z = "2*cm" />
       <position z_offset = "20.0*m" rotation = "false" vmax = "10*cm" v = "0.5*cm" />
       <layer repeat = "5">
-        <slice material="Carbon"  thickness="0.5*mm"  vis = "BlueVis" />
-        <slice material="Silicon" thickness="0.3*mm"  vis = "GreenVis" sensitive = "true"  />
-        <slice material="Carbon"  thickness="0.5*mm"  vis = "BlueVis" />
+        <slice material="SiliconNitride"  thickness="0.001*mm"  vis="BlueVis" />
+        <slice material="Silicon" thickness="0.03*cm" vis="GreenVis" sensitive="true"  />
         <slice material="Vacuum"  thickness="1.0*mm"  vis="InvisibleWithDaughters" />
       </layer>
     </detector>
diff --git a/trackers/roman_pot_simu.sh b/trackers/roman_pot_simu.sh
index c10ac633f8e131ca1ba7b12367996ac803715ad5..7f15f490dcdcaf8694db65736c28304c8c728a44 100755
--- a/trackers/roman_pot_simu.sh
+++ b/trackers/roman_pot_simu.sh
@@ -3,6 +3,6 @@
 source /usr/local/bin/thisdd4hep.sh
 
 ddsim --runType batch -N 300 \
-	--inputFiles ../data/forward_ions.hepmc \
-	--compactFile ./roman_pot.xml \
-	--outputFile ../sim_output/roman_pot_out.root
+	--inputFiles ./data/forward_ions.hepmc \
+	--compactFile ./trackers/roman_pot.xml \
+	--outputFile ./sim_output/roman_pot_out.root
diff --git a/trackers/simple_tracking.cxx b/trackers/simple_tracking.cxx
index b394bb91e6675025dceeaa7d8fab58d6d7f0a059..fc2febb29f0a801db492073aae434055e625271b 100644
--- a/trackers/simple_tracking.cxx
+++ b/trackers/simple_tracking.cxx
@@ -29,7 +29,7 @@ R__LOAD_LIBRARY(libDDG4IO.so)
 //#include "lcio2/TrackerRawDataData.h"
 //#include "lcio2/TrackerRawData.h"
 
-void simple_tracking(const char* fname = "../sim_output/roman_pot_out.root"){
+void simple_tracking(const char* fname = "./sim_output/roman_pot_out.root"){
 
   ROOT::EnableImplicitMT(); // Tell ROOT you want to go parallel
   //using namespace lcio2;