David Philipson
Filter David's content
ERC-4337 dummy signatures and gas token transfers
Learn how to get preVerificationGas and verificationGasLimit fields during the user operation gas estimation process using a dummy signature and dummy paymasterAndData value.
How ERC-4337 gas estimation works
Learn how Alchemy engineers developed an ERC-4337 bundler in Rust that provides accurate user operation gas estimations, and explore suggested changes to the entry point contract to make the gas estimation process easier.
ERC-4337 gas estimation for L2s and signature aggregators
Learn how Alchemy's ERC-4337 Bundler handles gas estimation for gas fees that are not metered by the entry point contract including signature aggregators and layer 2 transactions including Optimism and Arbitrum.
How user operation fees are estimated and charged
Learn how bundlers are incentivized, how bundlers estimate user operation gas fees, and how senders estimate user op fees on Arbitrum and Optimism.
Account abstraction part 4: aggregate signatures
Explore ERC-4337's breakthrough with aggregate signatures. Streamline multiple user op validations using a single cryptographic signature, enhancing transaction efficiency.
Account abstraction part 2: sponsoring transactions using paymasters
Learn how paymasters, paymaster staking, and paymaster postOp methods enable the sponsoring of transactions according to Account Abstraction as detailed in ERC-4337.
Account abstraction part 3: wallet creation
Learn how to create and deploy smart contract wallets and counterfactual addresses with CREATE2, and about factories, which specialize in creating different kinds of wallet contracts.
You could have invented account abstraction: part 1
Learn how to create a smart contract wallet to protect your most valuable assets and how they rely on a bundler to call smart contract wallets on your behalf.