a bit o' spruce, from http://play.spruce.cf

spruce.json

{"flavor":"1.16.0","prune":["meta"],"env":["HOME=/home/user"],"cherry_pick":[],"yaml":[{"filename":"file1.yml","contents":"groups:\n- (( merge ))\n- name: (( grab meta.git.branch ))\n  jobs: \n  - (( prepend ))\n  - (( grab meta.build.job ))\n  resources:\n  - (( prepend ))\n  - git-pipeline\n  - maven-build\n"},{"filename":"file2.yml","contents":"---\ngroups:\n- (( merge ))\n- name: ((grab meta.git.branch))\n  resources:\n  - (( prepend ))\n  - osb-bosh-java\n  jobs:\n  - (( prepend ))\n  - testflight\n"}],"skip_eval":false,"fallback_append":false,"go_patch":false,"debug":false,"trace":false}