The toolkit this site runs on

Membership proof

import * as snarkjs from "snarkjs";
import {
  createIdentity, leafOf, MemberTree, scopeOf,
  proveEligibility, toBundle, proofCalldata,
} from "@zksium/sdk";

// 1. Member: make an identity, send only the leaf to the gate admin.
const me = createIdentity();             // keep me.secret private
const leaf = leafOf(me);

// 2. Rebuild the gate's tree from its MemberAdded logs (index order)
//    and compare tree.root with the contract's currentRoot(gateId).
const tree = new MemberTree(leaves);
const i = tree.indexOf(leaf);

// 3. Prove for a recipient. The scope binds the nullifier to this gate.
const scope = scopeOf(99901, GATE, gateId);
const files = { wasm: "eligibility.wasm", zkey: "eligibility.zkey" };
const p = await proveEligibility(snarkjs, files, me, tree.path(i), scope, recipient);

// 4. Send claimEligibility(gateId, recipient, p.root, p.nullifier, proofCalldata(p.proof))
//    from any address, or hand toBundle(p, 99901, GATE, gateId) to a checker.

Threshold proof

import { createAttribute, commitmentOf, exportAttribute,
  importAttribute, proveThreshold } from "@zksium/sdk";

// Attester: asks the holder for their leaf (never their secret)
const attr = createAttribute(250n, holderLeaf); // value + salt + holder
const c = commitmentOf(attr);            // publish: attest(c)
const handout = exportAttribute(attr);   // give privately to the holder

// Holder (only the identity behind holderLeaf can prove)
const a = importAttribute(handout);
const p = await proveThreshold(snarkjs, files, a, me, 100n, recipient);
// claimThreshold(gateId, recipient, p.commitment, proofCalldata(p.proof))

Check a bundle on Elysium

curl -s https://zksium.xyz/api/verify \
  -H 'content-type: application/json' \
  --data @zksium-proof.json
# {"valid":true,"block":5527811,"readAt":...}

Runs the generated verifier on Elysium's precompiles (eth_call + state override). 30 checks per 10 minutes per network.