What determines what version of docker compose is installed on the Elastic CI Stack for AWS?
At the time of writing it comes with 1.29.2 (Elastic CI Stack for AWS | Buildkite Documentation) but I need at least v2.4.1 as would like to use the ssh build option (ref: Docker Compose release notes | Docker Documentation)
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It’s great that you have found the references from GitHub - buildkite/elastic-ci-stack-for-aws: An auto-scaling cluster of build agents running in your own AWS VPC.
You could also explore building your own Elastic CI Stack if you want to have more control on the contents of your AWS instances.