Deterministic Contract Factory

This repository contains a factory contract which can be deployed to any chain on a deterministic address (i.e the same address in every chain). This factory contract in turn leverages CREATE2 to deploy contracts at deterministic locations.

Rationale

Why would you use such a contract ?

The main idea behind this concept is that you can deploy the factory on top of any network at a deterministic address and then use it to deploy other contracts in the same fashion. This can be useful, for example, to deploy "network level contracts" (i.e singleton contracts) on any network on the same addresses, this way you can reduce the amount of setup needed for your applications by assuming the contracts are always present at the same addresses.

For example: I can deploy my dapp that relies on N singleton contracts on top of any network and assume those singleton contracts are going to be deployed on the same addresses everytime, allowing me to skip the steps in which I deploy the contracts, get the addresses in which they have been deployed and then configure the rest of my components to point to those addresses.

With enough thought you could even deploy your entire dapp and not only the singleton contracts into the same addresses on every network. Yay !!

How does it work ?

To make this possible we leverage two things:

Keyless Deployment Method:

In Ethereum to create a valid transaction, your first have to sign it using a private key. When we think about a transaction, something like this might come to mind:
```
    Transaction: {
        from: '',
        to: '',
        value: 0,
        data: '',
        ...
    }
```
But in reality the from field is not set explicitly by the sender, instead it's computed from the signature of the transaction via a function called ecrecover. Since only the owner of that address can generate signatures that return that address only they can authorize the network to spend funds from their account.

So the question is, what would happen if instead of signing the transaction the normal way, we filled the signature with some seemingly random values? It turns out that 50% of the time ecrecover returns a valid public key (and subsequently a valid address). With this in mind, we can build a transaction that can spend funds from a seemingly random addres all we need to do is fund it with enough ETH and we are good to go.

As such, and taking into account how the address of a contract is computed with CREATE (address = hash(sender, nonce)) we craft the factory deployment transaction and signatures and we are able to deploy the factory at a deterministic address in every network - because the private key for that address is unknown, and we can prove that it's unknown by choosing the values in the signature in some predictable fashion thus proving to anyone that the address will only be usable for that transaction.

Caveats:

We have to make sure that the crafted transaction can always be executed, as such we need to choose a pretty high gas price and send enough ETH to our "one-use address" so its able to execute it. As such, the cost of deployment will be pretty high but on the positive side we only need to deploy once per network.
CREATE2:

It's an opcode introduced in the Constantinople hard fork which provides an alternative to the original CREATE. The main difference is that the address of the deployed contract is computed by the formula address = hash(creator address, salt, contract creation code) Since none of these values depend on the state of the creator (remember that CREATE depends on the nonce) this means that we can guarantee that the contract will be deployed at the same address independently of the state of the sender.

Caveats:

Since the address of the contract now depends on the contract creation code we have to make sure its deterministic to be able to get the same address everytime. For example, an ownable contract creation code will change depending on who the owner is set to be. To get around this issue, we can use initializers instead of contructors.

What you need

Deployment Transaction

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

Generated Keyless Address (Factory Deployer)

0x1107Dd08bBeE561a2b571D0be982959503120c1e