diff --git a/_service b/_service
index 103f106..231be7e 100644
--- a/_service
+++ b/_service
@@ -11,4 +11,8 @@
+
+ *.tar
+ xz
+
diff --git a/b4.spec b/b4.spec
index 1bee940..711d5a5 100644
--- a/b4.spec
+++ b/b4.spec
@@ -25,7 +25,7 @@ Summary: Helper scripts for kernel.org patches
License: GPL-2.0-or-later
Group: Development/Tools/Other
URL: https://git.kernel.org/pub/scm/utils/b4/b4.git
-Source0: %{name}-%{version}.tar
+Source0: %{name}-%{version}.tar.xz
BuildArch: noarch
BuildRequires: %{python_module setuptools}
BuildRequires: tar