diff --git a/coq.spec b/coq.spec
index a027a71..a3ab8e7 100644
--- a/coq.spec
+++ b/coq.spec
@@ -86,10 +86,12 @@ export CFLAGS='%{optflags}'
    -natdynlink yes \
    -browser "xdg-open %s"
 
-# Prevent OOM by limiting the number of threads.
-%define _smp_ncpus_max %(awk '/MemAvailable/ { print int($2 / 750000) }' /proc/meminfo)
+jobs=%{_smp_build_ncpus}
+max_jobs=$(awk '/MemAvailable/ { print int($2 / 1750000) }' /proc/meminfo)
+test $max_jobs -lt $jobs && jobs="$max_jobs" && \
+	echo "Warning: Reducing number of jobs to $max_jobs because of memory limits"
 
-make %{?_smp_mflags} world
+make -j $jobs world
 
 %install
 make COQINSTALLPREFIX=%{buildroot} install