Foundation of gasless meta-transactions.
Related terms
ERC-4337 (account abstraction)
Ethereum standard for smart-contract wallets without a consensus-layer change.
Oracle (blockchain)
A service that feeds real-world data - a price, a match result, the weather - into a smart contract, which otherwise can't see outside its own chain.
Paymaster
ERC-4337 contract that pays gas for UserOps.
Reentrancy
A smart-contract bug where an external call lets an attacker re-enter your function before its state updates - the flaw behind the 2016 DAO hack.
The bench this belongs to
BlockchainSolidity on Ethereum, Polygon, Base and Arbitrum. Anchor programs on Solana. Written with tests first, because a redeploy is not a hotfix once value is on the line.
