diff --git a/_service b/_service
index ae01baa..2dfcc9b 100644
--- a/_service
+++ b/_service
@@ -1,15 +1,15 @@
 <services>
-	<service name="tar_scm" mode="disabled">
+	<service name="tar_scm" mode="manual">
 		<param name="filename">carat</param>
 		<param name="scm">git</param>
 		<param name="url">https://github.com/lbfm-rwth/carat</param>
-		<param name="revision">master</param>
+		<param name="revision">21bfdb516cc21c8e634a9fc99c469a07b8c7490c</param>
 		<param name="parent-tag">v2.1b1</param>
-		<param name="versionformat">2.1b1+g@TAG_OFFSET@</param>
+		<param name="versionformat">2.1b1+g@TAG_OFFSET@.%h</param>
 	</service>
-	<service name="recompress" mode="disabled">
+	<service name="recompress" mode="manual">
 		<param name="file">*.tar</param>
 		<param name="compression">xz</param>
 	</service>
-	<service name="set_version" mode="disabled"/>
+	<service name="set_version" mode="manual"/>
 </services>
diff --git a/carat-2.1b1+g132.21bfdb5.tar.xz b/carat-2.1b1+g132.21bfdb5.tar.xz
new file mode 100644
index 0000000..c1d2333
--- /dev/null
+++ b/carat-2.1b1+g132.21bfdb5.tar.xz
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:d9653c143c1f6fc27fb9e7542c127847b1a39a2f1028810c5409de479e5b1feb
+size 5695280
diff --git a/carat-2.1b1+g132.tar.xz b/carat-2.1b1+g132.tar.xz
deleted file mode 100644
index 5dd6cdb..0000000
--- a/carat-2.1b1+g132.tar.xz
+++ /dev/null
@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:7245ac04ec91378005c1e6a4f8c9c46aa938d6c1029bb6653eadad4cb7af12aa
-size 5696840
diff --git a/carat.changes b/carat.changes
index 2132a40..54dd8d9 100644
--- a/carat.changes
+++ b/carat.changes
@@ -1,3 +1,9 @@
+-------------------------------------------------------------------
+Fri Sep 13 10:42:35 UTC 2024 - Jan Engelhardt <jengelh@inai.de>
+
+- Switch _service to an explicit revision hash to facilitate
+  tarball verification.
+
 -------------------------------------------------------------------
 Sat Jun 24 13:47:39 UTC 2023 - Jan Engelhardt <jengelh@inai.de>
 
diff --git a/carat.spec b/carat.spec
index 9665662..fe9920a 100644
--- a/carat.spec
+++ b/carat.spec
@@ -1,7 +1,7 @@
 #
-# spec file for package pari
+# spec file for package carat
 #
-# Copyright (c) 2022 SUSE LLC
+# Copyright (c) 2024 SUSE LLC
 #
 # All modifications and additions to the file contributed by third parties
 # remain the property of their copyright owners, unless otherwise agreed
@@ -17,7 +17,7 @@
 
 
 Name:           carat
-Version:        2.1b1+g132
+Version:        2.1b1+g132.21bfdb5
 Release:        0
 Summary:        Programs for solving certain tasks in mathematical crystallography
 License:        GPL-2.0-only
@@ -34,8 +34,9 @@ construction, recognition and comparison problems for
 crystallographic groups up to dimension 6. The name CARAT itself
 is an acronym for Crystallographic AlgoRithms And Tables.
 
-# Utilies invoked from e.g. gap-caratinterface
 
+
+# Utilies invoked from e.g. gap-caratinterface
 %prep
 %autosetup