SRC20

Privacy-preserving ERC20 tokens with shielded balances

SRC20 is Seismic's privacy-preserving ERC20. Balances and transfer amounts use shielded types (suint256), so they're hidden from external observers. The SDK ships with SRC20_ABI built in.

from seismic_web3 import create_wallet_client, SRC20_ABI, PrivateKey

w3 = create_wallet_client("http://127.0.0.1:8545", private_key=PrivateKey(...))

token = w3.seismic.contract(address="0x...", abi=SRC20_ABI)

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Metadata

Token metadata isn't shielded, so you can use plain transparent reads:

name = token.tread.name()         # b"TestToken"
symbol = token.tread.symbol()     # b"TEST"
decimals = token.tread.decimals() # b'\x12' (18)

---

Balances

raw = token.read.balanceOf()
balance = int.from_bytes(raw, "big")

balanceOf() takes no arguments. The contract uses msg.sender internally, so you must use .read (a signed read) — not .tread. A plain eth_call zeros out the from field, which means the contract sees the zero address as the sender and returns its balance — which is almost certainly zero.

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Approvals

Approve a spender to transfer tokens on your behalf, then have them call transferFrom:

# Approve
tx_hash = token.write.approve("0xSpender...", 500)
w3.eth.wait_for_transaction_receipt(tx_hash)

# Check allowance — transparent read, no signed read needed
raw = token.tread.allowance("0xOwner...", "0xSpender...")
allowance = int.from_bytes(raw, "big")

---

Transfers

# Direct transfer
tx_hash = token.write.transfer("0xRecipient...", 100)
receipt = w3.eth.wait_for_transaction_receipt(tx_hash)

# Transfer on behalf of owner (called by the approved spender)
tx_hash = token.write.transferFrom("0xOwner...", "0xRecipient...", 100)