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

spruce.json

{"flavor":"1.13.0","prune":["meta"],"env":["HOME=/home/user"],"cherry_pick":[],"yaml":[{"filename":"a.yml","contents":"--- # a.yml\ninstance_groups:\n- name: db\n  jobs:\n  - release: postgres\n    name: postgres\n    jobs:\n    - name: postgres-stuff\n    - name: agent-pgtools\n    \n"},{"filename":"b.yml","contents":"--- # b.yml\ninstance_groups:\n- name: db\n  jobs:\n  - name: postgres\n    jobs:\n    - (( delete agent-pgtools ))\n\n\n\n\n\n\n"}],"skip_eval":false,"fallback_append":false,"go_patch":false,"debug":false,"trace":false}