Use the built-in JSON example with app, enabled, ports and limits. Add the member "build": 900719925474099312345 and "note": null. Convert with two spaces. The output keeps member and list order, quotes every key and string, and retains every digit of build.
Expected checks
The root type is Object. ports remains a two-item sequence, limits remains a mapping, enabled remains boolean true, note remains null and build is not rounded. Downloaded output is converted.yaml. Parsing that output back through the YAML-to-JSON direction must reproduce the same JSON-compatible tree.
The destination parser is authoritative
Keep the original, diff the complete output and parse the result with the exact library or application that will consume it. JSONYAML proves only that one bounded document fits its declared JSON-compatible profile. It does not validate a destination schema, environment substitution, application defaults, deployment behavior or semantic correctness.