Subtract from the sender. Add to the receiver. Vyper’s explicit syntax keeps the movement of value easy to follow.
# Two balances. One transfer.
self.balanceOf[sender] -= amount
self.balanceOf[receiver] += amount↳ No class inheritance. No hidden modifiers.
A uint8 holds 0–255. Go past that limit and standard arithmetic reverts, instead of silently wrapping back to zero.
@external
@pure
def add(a: uint8, b: uint8) -> uint8:
return a + b255 + 1 → REVERT The overflow never becomes a balance.
Eight iterations, declared up front. Bounded loops and no recursion make execution limits easier to inspect.
total: uint256 = 0
for i: uint256 in range(8):
total += i8 ITERATIONS MAX Bounded work doesn’t mean a fixed gas price.
The ERC-20 ledger and Uniswap v4 callbacks live in the same contract. The pool uses one address for both.
ETHEREUM · WRITTEN IN VYPERLaunch caps expire automatically. The deployer and PoolManager are exempt from the wallet cap; deployer-to-pool liquidity funding is exempt from the transfer cap. Swaps remain capped during the launch window.
Wallet transfers and other pools aren’t taxed by this hook. ETH accumulates in the combined coin/hook contract; anyone can trigger a claim, but only the original coin deployer receives it.
Partial fills of specified ETH amounts revert to prevent overcharging. A language helps with security; it doesn’t replace testing or an independent audit.
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