The repository mixed both extensions, the molecule scenario used yml while the role itself used yaml. The yml extension is the one ansible-galaxy and molecule generate, so it is applied throughout and across the sibling roles. The include_tasks calls in tasks/main.yml and tasks/create_unix_user.yml name their target explicitly and were adjusted accordingly, otherwise the role would no longer find the included task files. Co-authored-by: Copilot <copilot@github.com>