Confium Privacy

Compute on shared data without revealing the inputs. PSI is the canonical starting point.

1. 1

   Add the crate

   cargo add confium-privacy

   cargo add confium-privacy

2. 2

   Pick a primitive

   PSI, PIR, DP, MPC, ring sigs, blind sigs, VRF, VDF.

   use confium_privacy::psi::EcdhPsi;
   use confium_privity::pir::SealPir;
   use confium_privacy::dp::ZcdpBudget;
   // 15+ primitives available

3. 3

   Run a 2-party PSI

   Find the intersection of two sets without revealing them.

   let server = EcdhPsi::new(vec!["alice@ex.com".to_string()]);
   let request = server.request();
   
   let client_set: Vec<String> = vec!["alice@ex.com".into(), "carol@ex.com".into()];
   let response = server.respond(client_set.iter().map(|s| s.as_bytes()));
   
   let intersection = EcdhPsi::client_compute(&request, &response);
   // → {"alice@ex.com"}

4. 4

   Verify the result

   Confirm only the intersection was revealed.

   // Server never learned client_set.
   // Client only learned the intersection, not the server set beyond that.
   assert_eq!(intersection, vec!["alice@ex.com"]);

5. 5

   Adapt

   Swap primitives; same ergonomics.

   // Same flow for ring sigs, VRFs, blind sigs, etc.
   use confium_privacy::ring_sig::RingSig;
   use confium_privacy::vrf::Ecvrf;
   
   let sig = RingSig::sign(&privkey, &[pubkey1, pubkey2, pubkey3], msg)?;
   // Verifier can confirm ONE of {pubkey1, pubkey2, pubkey3} signed,
   // but not which.