Preinstalls

important

These are deployed at fixed addresses right from the chain’s genesis, but they are developed by third parties. So, do your own research.

Why? Certain widely used contracts (like Safe, Multicall3 or create2Deployer) are “preinstalled” for convenience. Developers don’t need to redeploy them. The thing is that OP team is not directly responsible for their code.

Safe and SafeL2: both are multi-sig wallets that support confirmations via signed messages (ERC191). The main difference is that SafeL2 emits events, and Safe don’t.
MultiSend and MultiSendCallOnly: batch multiple transactions into a single one, handy for complex operations. CallOnly variant restricts the batched ops to CALL instructions (no delegatecall, etc.)
SafeSingletonFactory: Used by Safe-related contracts for deterministic deployment, referencing Arachnid’s approach. Includes chain ID in the pre-signed tx to avoid cross-chain replay issues.
Multicall3: it would be use for aggregating read calls in one RPC request (gasless for read-only) or executing multiple state changes in a single transaction.
Create2Deployer: it is a wrapper for CREATE2deployments → so you can predict the contract address ahead of time. It also includes a special function to deploy the ERC1820 implementer.
CreateX: it extends the CREATE2/CREATE3 logic with extra salt protection.
Arachnid’s Deterministic Deployment Proxy: Another approach to cross-chain deterministic deployments. Uses a one-time-use “deployer account” so the address is always the same across any chain.
Permit2: Next-gen token approval system (meta-transactions), simplifying token approvals across dApps.
ERC-4337 EntryPoint / SenderCreator (v0.6.0 & v0.7.0): Core contracts for ERC-4337’s account abstraction, verifying and executing batches of UserOperations. The SenderCreator is used to deploy new smart accounts in a neutral context.