diff --git a/.github/workflows/cmake_ubuntu.yml b/.github/workflows/cmake_ubuntu.yml
index c718e7ab2..9bbc22578 100644
--- a/.github/workflows/cmake_ubuntu.yml
+++ b/.github/workflows/cmake_ubuntu.yml
@@ -74,7 +74,7 @@ jobs:
         set -ex
         cmake $GITHUB_WORKSPACE
         cd ${{runner.workspace}}/PHARE/subprojects/samrai && mkdir build && cd build
-        cmake .. -DENABLE_SAMRAI_TESTS=OFF -DCMAKE_BUILD_TYPE=RelWithDebInfo
+        cmake .. -DENABLE_SAMRAI_TESTS=OFF -DCMAKE_BUILD_TYPE=Debug
         make -j2 && sudo make install && cd ../.. && rm -rf samrai
         cd ${{runner.workspace}}/build && rm -rf *
         cmake $GITHUB_WORKSPACE -DCMAKE_VERBOSE_MAKEFILE:BOOL=ON --fresh \
@@ -82,7 +82,7 @@ jobs:
               -DCMAKE_C_COMPILER_LAUNCHER=ccache \
               -DCMAKE_CXX_COMPILER_LAUNCHER=ccache \
               -DlowResourceTests=ON -DdevMode=ON -Dbench=ON \
-              -DCMAKE_CXX_FLAGS="-DPHARE_DIAG_DOUBLES=1 " -Dphare_configurator=ON
+              -DCMAKE_CXX_FLAGS="-O3 -DPHARE_DIAG_DOUBLES=1 " -Dphare_configurator=ON
 
     - name: Build
       working-directory: ${{runner.workspace}}/build