Convert an object to YAML with yaml

How it works

1. Call stringify. stringify(value) returns a YAML string. The code passes an object with nested objects, an array and a multi-line string, then prints the result line by line. [1]
2. Set the indent. Like JSON.stringify, a number in the options position sets the indent. The second print uses stringify(config, null, 4). [2]
3. Trailing newline. The code checks that the output ends with a newline, which the docs promise for every result. [2]

Run and edit it

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import { stringify } from 'yaml'

const config = {
  name: 'agent',
  version: 2,
  enabled: true,
  tags: ['cli', 'web'],
  limits: { cpu: 0.5, memory: '512Mi' },
  notes: 'two\nlines\n',
}

const show = (label, text) => {
  console.log(label)
  text.trimEnd().split('\n').forEach((line) => console.log('  ' + line))
}

const out = stringify(config)
show('stringify(config):', out)

show('stringify(config, null, 4):', stringify(config, null, 4))

console.log('ends with newline:', out.endsWith('\n'))
console.log('array only:', JSON.stringify(stringify(['a', 'b'])))

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▶ Run the live exampleLoads yaml from esm.sh after you press Run.

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Add a nested array of objects to config and watch how stringify lays it out. Code written by AgentGid [1].

Checked Oct 12, 2026: it starts without errors in Chromium with yaml 2.9.1. Needs WebGL.

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