SRC20 Workflow

Read metadata, check balance, approve, and transfer with SRC20

End-to-end example using the SRC20 token standard — Seismic's privacy-preserving ERC20.

import os
from eth_abi import decode
from seismic_web3 import PrivateKey, SEISMIC_TESTNET, SRC20_ABI

pk = PrivateKey.from_hex_str(os.environ["PRIVATE_KEY"])
w3 = SEISMIC_TESTNET.wallet_client(pk)

token = w3.seismic.contract("0xYourTokenAddress", SRC20_ABI)

# 1) Read token metadata (transparent reads — no auth needed)
name = decode(["string"], bytes(token.tread.name()))[0]
symbol = decode(["string"], bytes(token.tread.symbol()))[0]
decimals = decode(["uint8"], bytes(token.tread.decimals()))[0]
print(name, symbol, decimals)

# 2) Read your balance (signed read — proves identity)
balance = decode(["uint256"], bytes(token.read.balanceOf()))[0]
print("balance", balance)

# 3) Approve and transfer (shielded writes)
approve_tx = token.write.approve("0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266", 500)
w3.eth.wait_for_transaction_receipt(approve_tx)

transfer_tx = token.write.transfer("0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266", 100)
receipt = w3.eth.wait_for_transaction_receipt(transfer_tx)
print("transfer status", receipt["status"])

Notes

• balanceOf() takes no arguments — it uses msg.sender, so you must use .read (signed read), not .tread

• approve and transfer amounts use shielded types (suint256) — encrypted in the transaction calldata

• Transparent metadata like name(), symbol(), and decimals() can use .tread since they don't depend on the caller

See Also

• SRC20 Documentation — Full token standard reference

• Signed Reads — Why .read is needed for balanceOf()

• Shielded Write — How .write encrypts calldata