specular

Specular Client

Running a local network

This guide will demonstrate how to set up a rollup network containing L2 sequencer nodes, running over a Hardhat L1 node---all on your local machine. After the 3 nodes are running, you can use MetaMask to send custom transactions to the sequencer, and see how transactions are executed on the L2 network, sequenced to the L1 network, and confirmed. In this example, all nodes operate honestly (no challenges are issued).

Build

Install all dependencies and build the modified L2 Geth node

cd SPECULAR_REPO
pnpm install

cd SPECULAR_REPO/clients/geth/specular
make install

Generate the genesis file

cd SPECULAR_REPO/config/sbin
./create_genesis.sh

L2 setup

cd SPECULAR_REPO/clients/geth/specular/sbin
./import_accounts.sh && ./init.sh

L1 local dev node installation

See here for more details.

Start nodes

# Terminal #1: start L1 node
pnpm install
cd contracts
npx hardhat node

# Terminal #2: start sequencer
cd SPECULAR_REPO/clients/geth/specular/sbin
./start_sequencer.sh

Make sure there are logs for Sequencer started and Validator started in the respective consoles. In the first terminal where L1 node is running, you can see the sequencer staked on the Rollup contract.

Restarts

Currently, the sequencer must start in a clean environment; i.e. you need to clean and reinitialize both L1 and L2 on every start.

To restart the L1 node, use Ctrl-C to stop the current running one and run npx hardhat node again.

To reinitialize L2 node, under sbin directory, run ./clean.sh && ./init.sh.

Do not forget to reset MetaMask account if you have sent some transactions on L2 (see below for more details).

Transact using MetaMask

Configuration

1. Go to data/keys, import the sequencer key to MetaMask. Both accounts are pre-funded with 10 ETH each on L2 network, and you can use them to send transactions. Note: on L2, these two accounts are just normal accounts; not to be confused with the sequencer roles on L1 (the addresses are just being reused).
2. In Settings -> Networks, create a new network called L2 which connects to the sequencer. The sequencer node should be running while creating the network. Enter http://localhost:4011 for RPC URL, 13527 for Chain ID, ETH for currency symbol (we haven't changed the symbol yet).

Transact

Remember to reset the account after every clean start of the network. Select the appropriate account, go to Setting -> Advanced, and click Reset Account. This ensures the account nonce cache in MetaMask is cleared.

Now, you can use the pre-funded account to send transactions.

After an L2 transaction, in the Hardhat node console, observe the resultant transactions occuring on L1:

• sequencer calls appendTxBatch to sequence transaction
• sequencer calls createAssertion to create disputable assertion
• sequencer calls confirmFirstUnresolvedAssertion to confirm the assertion after every stakers staked on the assertion

Make sure that sequencer node is started before sending any transaction to L2.

Scenario Parameters

L1: Hardhat, chain ID 31337, http/ws on port 8545.

L2: Chain ID 13527. Sequencer: http on port 4011, ws on port 4012; Validator: http on port 4018, ws on port 4019.

License

The Golang binding of Specular L2 contracts (files under bindings directory) is licensed under the Apache License 2.0, see LICENSE for details.

The Specular client binary (files under cmd directory) is directly modified from of the go-ethereum binary. It is licensed under the GNU General Public License v3.0 in accordance with the original license, see COPYING for details. Major modifications are marked with <specular modifications>.

Files under internal directory are directly copied from the go-ethereum library, which is originally licensed under the GNU Lesser General Public License v3.0, see COPYING for details.

The Specular proof module (files under proof directory) is licensed under the Apache License 2.0, see LICENSE for details.

The Specular rollup module (files under rollup directory) is licensed under the GNU Lesser General Public License v3.0, see COPYING.LESSER for details.