diff --git a/build_proton.sh b/build_proton.sh
index d75d7897..c5c94546 100755
--- a/build_proton.sh
+++ b/build_proton.sh
@@ -16,7 +16,7 @@ usage()
 
 set -e
 
-JOBS=-j5
+JOBS=-j"$(( $(nproc 2>/dev/null||sysctl -n hw.ncpu 2>/dev/null||echo 4) + 1))"
 PLATFORM=$(uname)
 
 [ -z "$STEAM_RUNTIME" ] && STEAM_RUNTIME="$HOME/steam-runtime"