diff --git a/conda/build-nersc.sh b/conda/build-nersc.sh
index 584bd73..7be3c6c 100755
--- a/conda/build-nersc.sh
+++ b/conda/build-nersc.sh
@@ -19,15 +19,6 @@ scratchBuildDir=/global/cscratch1/sd/heatherk/td_env-devbuilds
 commonDevBuildDir=/global/common/software/lsst/cori-haswell-gcc/stack/td_env-dev
 commonProdBuildDir=/global/common/software/lsst/cori-haswell-gcc/stack/td_env-prod
 
-#echo "REF_NAME " $CI_COMMIT_REF_NAME
-#echo "COMMIT_BRANCH " $CI_COMMIT_BRANCH
-#echo "SLUG " $CI_COMMIT_REF_SLUG
-
-#if [ "$CI_COMMIT_REF_NAME" = "dev" ];
-#then
-#    echo "Found DEV"!
-#fi
-
 if [ "$installFlag" ] && [ "$CI_COMMIT_REF_NAME" = "dev" ];  # Install dev
 then
     curBuildDir=$commonDevBuildDir/$CI_PIPELINE_ID
@@ -50,6 +41,7 @@ mkdir -p $curBuildDir
 cp conda/packlist.txt $curBuildDir
 cp conda/piplist.txt $curBuildDir
 cp nersc/setup_td_env.sh $curBuildDir
+cp nersc/sitecustomize.py $curBuildDir
 sed -i 's|$1|'$curBuildDir'|g' $curBuildDir/setup_td_env.sh
 cd $curBuildDir
 
diff --git a/nersc/setup_td_dev.sh b/nersc/setup_td_dev.sh
index c8a7599..dc4961c 100755
--- a/nersc/setup_td_dev.sh
+++ b/nersc/setup_td_dev.sh
@@ -98,6 +98,15 @@ then
   #export GSL_DIR=$CONDA_PREFIX
   #export CFITSIO_DIR=$CONDA_PREFIX
 
+  export PYTHONPATH=$PYTHONPATH:$DESC_TD_INSTALL
+
+  # SLURM_JOB_ID is set only on compute nodes
+  # DESC_TD_KEEP_MPI will be user-controlled way to keep MPI set up 
+  #if [[ -z "$DESC_TD_KEEP_MPI" && -z "$SLURM_JOB_ID" ]];
+  #then
+  #    export PYTHONSTARTUP=$DESC_TD_INSTALL/nompi4py.py
+  #fi
+
 fi
 
 # DIA Environment Variables
diff --git a/nersc/setup_td_env.sh b/nersc/setup_td_env.sh
old mode 100644
new mode 100755
diff --git a/nersc/sitecustomize.py b/nersc/sitecustomize.py
new file mode 100755
index 0000000..e6f6487
--- /dev/null
+++ b/nersc/sitecustomize.py
@@ -0,0 +1,6 @@
+import os
+if "DESC_TD_KEEP_MPI" not in os.environ:
+    if "SLURM_JOB_ID" not in os.environ:
+        import sys
+        sys.modules["mpi4py"] = None
+