How do we do deploys

We need to do deploys to:

• container schedulers
• (cook/play)books to configuration management systems
• ssh support would be nice
• zero-downtime deploys/feature flags/etc. would be nice https://about.gitlab.com/direction/cicd/

We need it for environment deploys and review apps https://gitlab.com/gitlab-org/gitlab-ce/issues/20255

Options:

1. CI script howto: redspread for k8, Ansible for BitBucket pipelines (hard to configure and test)
2. Runner plugins similar to drone plugins (hard to set up and test credentials, we have to maintain an interface and a registry, Drone plugins can't send structured data back, how does it work with every plugin being a container)
3. Project services, intuitive suggestion for deploy to Terraform (user friendly but unclear how that works since coordinator has to do the work instead of the Runner)
4. Deploy/environment API https://developer.github.com/v3/repos/deployments/ (we probably want to do the deployment instead of just an API for it)
5. A library like or similar to the dpl gem