Have you looked into Jsonnet/CUE/Dhall? They attempt to solve this problem, but give you an actual programming language instead. I've been using Jsonnet to succ

Have you looked into Jsonnet/CUE/Dhall? They attempt to solve this problem, but give you an actual programming language instead. I've been using Jsonnet to successfully escape the 'yaml-templating-yaml' hell for years now. But yeah, concourse configuration files are probably the worst YAML verbosity offenders, even worse than k8s manifests.