[0cf8612b2e1e]

JSONL is standard. Upthread said to write the header row and then make subsequent rows arrays. Of which I am not aware of anything that does this currently.

My objection to JSONL was about the increase in file size owing to repeating the keys.

[ianburrell]

JSON can write arrays in addition to hashes. JSON arrays are nearly identical to CSV. The only difference is brackets around li;es. There is no extra space wasted for keys.