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r14-examples

Runnable Rust demos for Root14's ZK privacy features on Stellar.

Repo structure​

PathWhat it doesNetwork
private-payments/Two-party shielded payment: keygen → deposit → Groth16 transfer → balanceOffline
zktls/TLS oracle → Poseidon commitment → testnet deposit → private ZK transferStellar testnet

Prerequisites​

  • Rust 1.75+ with cargo
  • ~2 GB RAM (Groth16 trusted setup is memory-intensive)
  • For zktls only: a configured wallet at ~/.r14/wallet.json — run r14_keygen then r14_config_set for stellar_secret, core_contract_id, and transfer_contract_id

Quick start​

git clone https://github.com/abhirupinspace/r14-example.git
cd r14-example

Private payments​

Full two-party payment flow with Groth16 proof generation (offline — no testnet required):

cargo run -p private-payments

Sample output:

=== 1. User A: Keygen ===
user_a owner_hash: 0x0077a584480a34...

=== 2. User B: Keygen ===
user_b owner_hash: 0x00a1c3f920b8e7...

=== 3. User A: Deposit 1000 ===
deposited 1000, commitment=0x41813dee706b4b...

=== 4. User A: Transfer 300 to User B ===
generating Groth16 proof...
proof:     a=0x1a2b3c4d5e6f7a8b...
nullifier: 0x42d39245306fdd...

=== 5. Final Balances ===
user_a:
  original note (1000): spent
  change note (700):    commitment=0x48f69c81b79b...
  balance: 700
user_b:
  received note (300):  commitment=0x3e8a7b6c5d4e...
  balance: 300

What happens under the hood:

  1. Generates BLS12-381 secret keys and Poseidon owner hashes for two users
  2. Creates a UTXO-style shielded note (value hidden behind a Poseidon commitment)
  3. Builds a Merkle membership path and generates a Groth16 proof that the sender owns the note, it exists in the tree, and output values balance
  4. The proof reveals nothing about amounts, sender, or recipient

zkTLS​

End-to-end flow: TLS oracle → Poseidon commitment → Stellar testnet deposit → private ZK transfer with Groth16 proof.

Prerequisites: a configured wallet at ~/.r14/wallet.json (run r14_keygen + r14_config_set first).

cargo run -p zktls

Sample output:

=== 0. Load Wallet ===
owner_hash: 0x0077a584480a34...
rpc:        https://soroban-testnet.stellar.org
indexer:    http://localhost:3000

=== 1. TLS Oracle: Fetch Private Data ===
source:     api.examplebank.com/balance
field:      account_balance_usd
session:    tls13_aead_aes256gcm_sha384_0x7f3a
value:      [REDACTED — known only to prover]

=== 2. Poseidon Commitment ===
commitment: 0x2f8a1b3c4d5e6f7a8b9c0d1e2f3a4b5c...
blinding:   [SECRET]
(commit = Poseidon(value, blinding) — hiding + binding)

=== 3. Deposit 15000 on Stellar Testnet ===
commitment: 0x41813dee706b4b...
tx:         success
deposited 15000 as shielded note

=== 4. Balance Check ===
total: 15000
  note 15000 | on_chain=true | tag=1

=== 5. Private Transfer (Groth16 ZK Proof) ===
bob owner:  0x00a1c3f920b8e7...
amount:     5000
generating Groth16 proof...
nullifier:  0x42d39245306fdd...
recipient:  0x3e8a7b6c5d4e...
change:     0x48f69c81b79b...
tx:         success

=== 6. Final Balance ===
total: 10000
  note 10000 | on_chain=true | tag=1

What it demonstrates:

  1. Loads wallet config and connects to Stellar testnet
  2. A TLS oracle fetches private data (bank balance)
  3. The prover commits to the value with Poseidon(value, blinding) — hiding and binding
  4. The committed value is deposited as a real shielded note on Stellar testnet
  5. A Groth16 ZK proof privately transfers part of the balance to a second user
  6. Balance updates reflect the transfer — value never revealed on-chain

Running tests​

Both examples include unit tests:

cargo test --workspace

Next steps​