What high-level problem are you trying to solve?
For multilateral deduplication, it would be great to have a data steward having their own ODK server centralising some data (say, Name+Date of Birth+Gender+pepper hashes), fed by many participating organisation that have each its own server. Conversely, it would be great if those participating organisations could have registration or follow-up forms where they can fetch Entities from the steward's centralised dataset, so that they can perform a hash comparison inside the form and see if it is a potential duplicate or an already known respondent.
In a slightly different way, this could also be useful for referrals and referral follow-ups.
Any ideas on how ODK could help you solve it?
The link in the "entities" tab could offer an URL or domain field besides the dataset name's field.
Of course, some kind of authentication should also be required (API token, or user/password...?)
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