3.25`distinctBy`

Integration developers frequently receive duplicate data.

Suppose:

[
  {"id": "C1", "name": "Acme"},
  {"id": "C1", "name": "Acme"},
  {"id": "C2", "name": "Widget"}
]

You can conceptually do:

payload distinctBy $.id

Result:

[
  {"id": "C1", "name": "Acme"},
  {"id": "C2", "name": "Widget"}
]

That said, don't treat DataWeave deduplication as a substitute for proper idempotency/external-ID design.