import YAML from "yawn-yaml/cjs"; import { load } from "js-yaml"; const src = ` prefix: '!' plugins: myplugin: config: can_do_thing: true # Lol can_do_other_thing: false `; const json = load(src); const yaml = new YAML(src); json.plugins.myplugin.config.can_do_thing = false; yaml.json = json; console.log(yaml.yaml);