We’re integrating self-hosted Invoice Ninja with an external identity service. We want separate external UUIDs on clients and client contacts, using a text custom field on each. Is this the recommended approach? Can these fields be kept internal and protected from manual edits? Are there any caveats around contact updates, merging records, or exact UUID lookup?
The unresolved issue is how reliably we maintain the reference, rather than whether Ninja can store it.