Making a Deposit

Deposits move USDC from your wallet into the Lateo privacy pool. A Groth16 ZK proof is generated and verified on-chain atomically.

Via Dashboard (Freighter)

Connect Freighter wallet on testnet
Click Deposit and enter an amount
Freighter prompts you to sign the transact() call
The pool contract atomically:
- Verifies the Groth16 proof
- Transfers USDC from your wallet to the pool
- Inserts a commitment into the Merkle tree
Your balance updates after on-chain confirmation

Via API (two-step)

Step 1: Prepare


curl -X POST http://localhost:3002/api/deposit/prepare \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer <jwt>" \
  -d '{"amount": "1.0000000", "publicKey": "GABC..."}'

Response:


{
  "prepareId": "uuid-...",
  "transactionXDR": "AAAA..."
}

The proxy generates a ZK proof, builds the unsigned transact() XDR, and simulates it.

Step 2: Sign and submit

Sign transactionXDR with Freighter or any Stellar wallet, then:


curl -X POST http://localhost:3002/api/deposit/submit \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer <jwt>" \
  -d '{"prepareId": "uuid-...", "signedTransactionXDR": "AAAA..."}'

Response:


{
  "status": "confirmed",
  "txHash": "819901e4...",
  "amount": "1.0000000",
  "zkProof": { "generated": true, "onChain": true }
}

Via MCP (localhost agents)


lateo_deposit(amount: "1")

The proxy generates the ZK proof and the operator signs transact() on behalf of the agent. No Freighter needed.

What happens on-chain

The transact() function on the pool contract executes atomically:

Calls the Groth16 Verifier contract to check the proof (BN254 pairing)
Verifies the Merkle root matches one of the stored roots
Verifies ASP membership (association set compliance)
Transfers USDC from sender to pool via SAC
Inserts two output commitments into the Merkle tree
Marks input nullifiers as spent

If any step fails, the entire transaction reverts. No USDC moves.