diff --git a/containers/singularity/Singularity b/containers/singularity/Singularity
index 5feee4388d985c83f484fda5b248aee383c7b289..643cf3f49851a472cfffc69d66a2e9b06b1f41a5 100644
--- a/containers/singularity/Singularity
+++ b/containers/singularity/Singularity
@@ -20,7 +20,7 @@ From: eicweb.phy.anl.gov:4567/whit/image_recipes/root_base:latest
   export LD_LIBRARY_PATH=/usr/local/lib:$LD_LIBRARY_PATH
   cd /tmp
   git clone --recurse-submodules https://eicweb.phy.anl.gov/jlab/simc-file-input.git && \
-    mkdir build && cd build && cmake ../simc-file-input && make -j20 install
+    mkdir build && cd build && cmake ../simc-file-input && make -j4 install
   cd /tmp && rm -rf build simc-file-input
 
 # ===================================