Hi, nodejs4 jobs in stein and older stable branches in horizon are now failing [1]. The symptom is that "yarn --version" fails during ensure-yarn [2]. It looks like that yarn now requires nodejs 10 or later and does not support nodejs4. The failure happens in the jobs on ubuntu-xenial nodes. When I try nodejs10 in stable/stein, the nodejs4 jobs (lint/run) succeeded [3]. My question is whether we need to install yarn in the pre-run? horizon does not require yarn. All nodejs jobs inherit nodejs-npm job defined in zuul/zuul-jobs and the pre-run playbook [4] installs yarn. I am not sure when we started to require yarn and who requires yarn. Generally speaking, I don't think it is a good idea to switch the nodejs version in these older stable branches. horizon and horizon plugins use nodejs only for testing, so if switching to nodejs10 would solve the failure completely, it might be an option too though. Thought? -amotoki [1] https://review.opendev.org/#/q/topic:health-check+status:open+project:openst... [2] https://zuul.opendev.org/t/openstack/build/72317c21cf7b4a1a885b9a26c5ae4c2d/... [3] https://review.opendev.org/#/c/726702/ [4] https://opendev.org/zuul/zuul-jobs/src/branch/master/playbooks/javascript/pr...