diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 99f6382dce..e1e45d13ea 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -154,6 +154,7 @@ stages:
 misc:sid:amd64:
   <<: *precheck_job
   script:
+    - sh util/check-ans-prereq.sh
     - sh util/checklibs.sh > checklibs.out
     - sh util/tabify-changes < CHANGES > CHANGES.tmp
     - diff -urNap CHANGES CHANGES.tmp
diff --git a/util/check-ans-prereq.sh b/util/check-ans-prereq.sh
new file mode 100644
index 0000000000..6c21d5c59d
--- /dev/null
+++ b/util/check-ans-prereq.sh
@@ -0,0 +1,26 @@
+#!/bin/sh
+#
+# Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+#
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+#
+# See the COPYRIGHT file distributed with this work for additional
+# information regarding copyright ownership.
+
+status=0
+
+for testscript in bin/tests/system/*/tests.sh; do
+	testdir="$(dirname "${testscript}")"
+	prereq="${testdir}/prereq.sh"
+	if [ -e "${prereq}" ] || [ -e "${prereq}.in" ]; then
+		continue
+	fi
+	if find "${testdir}" -type d -name "ans*" | grep -Eq "/ans[0-9]+$"; then
+		echo "missing ${prereq}"
+		status=1
+	fi
+done
+
+exit ${status}
diff --git a/util/copyrights b/util/copyrights
index 3725ce19f5..ca3e993f42 100644
--- a/util/copyrights
+++ b/util/copyrights
@@ -2585,6 +2585,7 @@
 ./util/COPYRIGHT.TOP				X	2018,2019
 ./util/bindkeys.pl				PERL	2009,2010,2011,2012,2014,2016,2017,2018,2019
 ./util/branchsync.sh				SH	2013,2016,2018,2019
+./util/check-ans-prereq.sh			SH	2019
 ./util/check-categories.sh			SH	2015,2016,2017,2018,2019
 ./util/check-changes				PERL	2002,2004,2007,2012,2016,2018,2019
 ./util/check-cocci				X	2018,2019