diff --git a/templates/Tests.yml.j2 b/templates/Tests.yml.j2
index c04cf1e..b4c3399 100644
--- a/templates/Tests.yml.j2
+++ b/templates/Tests.yml.j2
@@ -29,7 +29,8 @@ jobs:
       - run: |
           export HOME="/home/gap"
           cd /home/gap/.gap/pkg/
-          sudo apt update
+          # work around https://github.com/gap-system/gap-docker-base/issues/30
+          sudo apt -o Acquire::https::Verify-Peer="false" update
           sudo apt dist-upgrade -y
           sudo apt install -y texlive-latex-extra{% for apt_package in (ci_ubuntu_additional_apt_packages | default([ ])) %} {{ apt_package }}{% endfor %}
           cp ./{{ package.name }}/ci_gaprc /home/gap/.gap/gaprc