Engineering secure, high-concurrency bundler nodes that aggregate user operations into standard Ethereum transaction blocks.
ERC-4337 bundlers operate as pseudo-miners, aggregating off-chain UserOperations into single on-chain transactions sent to the EntryPoint smart contract. WalletHSM secures the bundler's private keys and validates incoming UserOperations against strict state constraints, preventing malicious operations from draining bundler gas reserves.
WalletHSM validates storage access rules and gas limits during simulation, instantly dropping UserOperations that access prohibited global state or exceed pre-calculated computational thresholds.