diff --git a/libguestfs.spec b/libguestfs.spec
index aa5ba54e5cf5a17dfbeb75e3ce495ca70062cc6a..5dbd0b8f86c275451c787cad3c15284e877b6cd4 100644
--- a/libguestfs.spec
+++ b/libguestfs.spec
@@ -4,7 +4,7 @@
 
 Name:          libguestfs
 Version:       1.40.2
-Release:       14
+Release:       15
 Epoch:         1
 Summary:       A set of tools for accessing and modifying virtual machine (VM) disk images
 License:       LGPLv2+
@@ -237,7 +237,7 @@ gzip -9 ChangeLog
 %make_install INSTALLDIRS=vendor NO_PACKLIST=1
 
 cd ../%{name}-%{version}-python3
-%make_install INSTALLDIRS=vendor -C python
+%make_install INSTALLDIRS=vendor -j16 -C python
 cd -
 
 rm $( find $RPM_BUILD_ROOT -name '*.a' | grep -v /ocaml/ )