diff --git a/scripts/debug.sh b/scripts/debug.sh
index 4c02361a8..86bcf6ad2 100755
--- a/scripts/debug.sh
+++ b/scripts/debug.sh
@@ -17,4 +17,4 @@ export LDFLAGS="$LDFLAGS -Wall -fsanitize=$sanitizers"
 
 cmake ../ -DCMAKE_BUILD_TYPE=Debug \
     -DCMAKE_INSTALL_PREFIX=/usr $@
-make -j$(nproc || echo 1)
+make -j $(nproc || sysctl -n hw.ncpu || echo 1)
diff --git a/scripts/minsize.sh b/scripts/minsize.sh
index 91b54fab2..790320b95 100755
--- a/scripts/minsize.sh
+++ b/scripts/minsize.sh
@@ -13,4 +13,4 @@ export CXXFLAGS="$CXXFLAGS -flto -fno-exceptions"
 
 cmake ../ -DCMAKE_BUILD_TYPE=MinSizeRel \
     -DCMAKE_INSTALL_PREFIX=/usr $@
-make -j$(nproc || echo 1)
+make -j $(nproc || sysctl -n hw.ncpu || echo 1)