diff --git a/.circleci/build-verilator.sh b/.circleci/build-verilator.sh
index 934025e3..a6780d1c 100755
--- a/.circleci/build-verilator.sh
+++ b/.circleci/build-verilator.sh
@@ -23,7 +23,7 @@ if [ ! -d "$LOCAL_VERILATOR_DIR" ]; then
     run "mkdir -p $REMOTE_CHIPYARD_DIR"
     copy $LOCAL_CHIPYARD_DIR/ $SERVER:$REMOTE_CHIPYARD_DIR
 
-    run "make -j8 -C $REMOTE_SIM_DIR VERILATOR_INSTALL_DIR=$REMOTE_VERILATOR_DIR verilator_install"
+    run "make -j$NPROC -C $REMOTE_SIM_DIR VERILATOR_INSTALL_DIR=$REMOTE_VERILATOR_DIR verilator_install"
 
     # copy so that circleci can cache
     mkdir -p $LOCAL_CHIPYARD_DIR
diff --git a/.circleci/defaults.sh b/.circleci/defaults.sh
index fb7a3571..66cf3b3d 100755
--- a/.circleci/defaults.sh
+++ b/.circleci/defaults.sh
@@ -17,6 +17,9 @@ clean () {
     run "rm -rf $REMOTE_WORK_DIR"
 }
 
+# make parallelism
+NPROC=8
+
 # remote variables
 REMOTE_WORK_DIR=$CI_DIR/$CIRCLE_PROJECT_REPONAME-$CIRCLE_BRANCH-$CIRCLE_SHA1-$CIRCLE_JOB
 REMOTE_RISCV_DIR=$REMOTE_WORK_DIR/riscv-tools-install
diff --git a/.circleci/do-rtl-build.sh b/.circleci/do-rtl-build.sh
index 68dbd7c8..c4eb04ab 100755
--- a/.circleci/do-rtl-build.sh
+++ b/.circleci/do-rtl-build.sh
@@ -41,7 +41,7 @@ fi
 
 # enter the verilator directory and build the specific config on remote server
 run "make -C $REMOTE_SIM_DIR clean"
-run "export RISCV=\"$TOOLS_DIR\"; export LD_LIBRARY_PATH=\"$LD_LIB_DIR\"; export VERILATOR_ROOT=$REMOTE_VERILATOR_DIR/install/share/verilator; make -j8 -C $REMOTE_SIM_DIR VERILATOR_INSTALL_DIR=$REMOTE_VERILATOR_DIR JAVA_ARGS=\"-Xmx8G -Xss8M\" ${mapping[$1]}"
+run "export RISCV=\"$TOOLS_DIR\"; export LD_LIBRARY_PATH=\"$LD_LIB_DIR\"; export VERILATOR_ROOT=$REMOTE_VERILATOR_DIR/install/share/verilator; make -j$NPROC -C $REMOTE_SIM_DIR VERILATOR_INSTALL_DIR=$REMOTE_VERILATOR_DIR JAVA_ARGS=\"-Xmx8G -Xss8M\" ${mapping[$1]}"
 run "rm -rf $REMOTE_CHIPYARD_DIR/project"
 
 # copy back the final build
diff --git a/.circleci/run-tests.sh b/.circleci/run-tests.sh
index 8cc11e10..4a6d9e7b 100755
--- a/.circleci/run-tests.sh
+++ b/.circleci/run-tests.sh
@@ -12,11 +12,11 @@ source $SCRIPT_DIR/defaults.sh
 export VERILATOR_ROOT=$LOCAL_VERILATOR_DIR/install/share/verilator
 
 run_bmark () {
-    make run-bmark-tests-fast -j8 -C $LOCAL_SIM_DIR VERILATOR_INSTALL_DIR=$LOCAL_VERILATOR_DIR $@
+    make run-bmark-tests-fast -j$NPROC -C $LOCAL_SIM_DIR VERILATOR_INSTALL_DIR=$LOCAL_VERILATOR_DIR $@
 }
 
 run_asm () {
-    make run-asm-tests-fast -j8 -C $LOCAL_SIM_DIR VERILATOR_INSTALL_DIR=$LOCAL_VERILATOR_DIR $@
+    make run-asm-tests-fast -j$NPROC -C $LOCAL_SIM_DIR VERILATOR_INSTALL_DIR=$LOCAL_VERILATOR_DIR $@
 }
 
 run_both () {
@@ -44,7 +44,7 @@ case $1 in
         export RISCV=$LOCAL_ESP_DIR
         export LD_LIBRARY_PATH=$LOCAL_ESP_DIR/lib
         export PATH=$RISCV/bin:$PATH
-        make run-rv64uv-p-asm-tests -j8 -C $LOCAL_SIM_DIR VERILATOR_INSTALL_DIR=$LOCAL_VERILATOR_DIR ${mapping[$1]}
+        make run-rv64uv-p-asm-tests -j$NPROC -C $LOCAL_SIM_DIR VERILATOR_INSTALL_DIR=$LOCAL_VERILATOR_DIR ${mapping[$1]}
         ;;
     *)
         echo "No set of tests for $1. Did you spell it right?"