diff --git a/.azure-pipelines.yml b/.azure-pipelines.yml
index 7e4edc2dc36..7c71599bbf3 100644
--- a/.azure-pipelines.yml
+++ b/.azure-pipelines.yml
@@ -18,6 +18,7 @@ jobs:
     LAPACKPP_HOME: '/usr/local'
     OMP_NUM_THREADS: 1
     WARPX_CI_CCACHE: 'TRUE'
+    WARPX_CI_CLEAN_TESTS: 'TRUE'
     WARPX_CI_NUM_MAKE_JOBS: 2
     WARPX_CI_OPENPMD: 'TRUE'
     WARPX_CI_TMP: '/tmp/ci'
diff --git a/Regression/Checksum/benchmarks_json/collisionXZ.json b/Regression/Checksum/benchmarks_json/collisionXZ.json
index f90c34bc86d..4fcf00ced62 100644
--- a/Regression/Checksum/benchmarks_json/collisionXZ.json
+++ b/Regression/Checksum/benchmarks_json/collisionXZ.json
@@ -7,20 +7,20 @@
     "Ey": 0.0,
     "Ez": 0.0
   },
-  "ion": {
-    "particle_momentum_x": 2.4932317055825563e-19,
-    "particle_momentum_y": 2.274916403334278e-19,
-    "particle_momentum_z": 2.2528161767665816e-19,
-    "particle_position_x": 2648815.601036139,
-    "particle_position_y": 2662836.7581390506,
+  "electron": {
+    "particle_momentum_x": 1.0618161248729303e-19,
+    "particle_momentum_y": 1.0331186403682394e-19,
+    "particle_momentum_z": 1.0375409035564829e-19,
+    "particle_position_x": 2652982.4592067804,
+    "particle_position_y": 2666143.4238272114,
     "particle_weight": 1.7256099431746894e+26
   },
-  "electron": {
-    "particle_momentum_x": 1.0489203687862582e-19,
-    "particle_momentum_y": 1.0209657029567292e-19,
-    "particle_momentum_z": 1.0248962872393911e-19,
-    "particle_position_x": 2657004.8285825616,
-    "particle_position_y": 2670174.272797987,
+  "ion": {
+    "particle_momentum_x": 2.4479519290953386e-19,
+    "particle_momentum_y": 2.2313460312794214e-19,
+    "particle_momentum_z": 2.207395147435577e-19,
+    "particle_position_x": 2666525.886108531,
+    "particle_position_y": 2666683.4040517565,
     "particle_weight": 1.7256099431746894e+26
   }
 }
diff --git a/run_test.sh b/run_test.sh
index 4efa86eb36c..275b7b5efb0 100755
--- a/run_test.sh
+++ b/run_test.sh
@@ -16,8 +16,10 @@
 # physically correct.
 
 # The tests can be influenced by environment variables:
+# Use `export WARPX_CI_CLEAN_TESTS=ON` in order to remove all subdirectories
+# from each test directory, directly after a test has passed.
 # Use `export WARPX_CI_DIM=3` or `export WARPX_CI_DIM=2` in order to
-# select only the tests that correspond to this dimension
+# select only the tests that correspond to this dimension.
 # Use `export WARPX_TEST_ARCH=CPU` or `export WARPX_TEST_ARCH=GPU` in order
 # to run the tests on CPU or GPU respectively.
 
@@ -30,6 +32,7 @@ tests_arg=$*
 tests_run=${tests_arg:+--tests=${tests_arg}}
 
 # environment options
+WARPX_CI_CLEAN_TESTS=${WARPX_CI_CLEAN_TESTS:-""}
 WARPX_CI_TMP=${WARPX_CI_TMP:-""}
 
 # Remove contents and link to a previous test directory (intentionally two arguments)
@@ -80,7 +83,7 @@ curl -sOL https://github.com/openPMD/openPMD-example-datasets/raw/4ba1d257c5b489
 cd -
 
 # Clone the AMReX regression test utility
-git clone https://github.com/AMReX-Codes/regression_testing.git
+git clone -b EZoni_rm_testdir https://github.com/EZoni/regression_testing.git
 
 # Prepare regression tests
 mkdir -p rt-WarpX/WarpX-benchmarks
@@ -93,12 +96,17 @@ cp -r Checksum ../../regression_testing/
 # Run tests
 cd ../../regression_testing/
 echo "cd $PWD"
+if [ -z "${WARPX_CI_CLEAN_TESTS}" ]; then
+    test_rm_dir=""
+else
+    test_rm_dir="--rm_testdir"
+fi
 # run only tests specified in variable tests_arg (single test or multiple tests)
 if [[ ! -z "${tests_arg}" ]]; then
-  python3 regtest.py ../rt-WarpX/ci-tests.ini --skip_comparison --no_update all "${tests_run}"
+  python3 regtest.py ../rt-WarpX/ci-tests.ini ${test_rm_dir} --skip_comparison --no_update all "${tests_run}"
 # run all tests (variables tests_arg and tests_run are empty)
 else
-  python3 regtest.py ../rt-WarpX/ci-tests.ini --skip_comparison --no_update all
+  python3 regtest.py ../rt-WarpX/ci-tests.ini ${test_rm_dir} --skip_comparison --no_update all
 fi
 
 # clean up python virtual environment