Arbitrum is a suite of Ethereum scaling solutions that enables high-throughput, low cost smart contracts while remaining trustlessly secure. Arbitrum has three modes: AnyTrust Channels, AnyTrust Sidechains, and Arbitrum Rollup. The following documentation describes how to use Arbitrum Rollup, which is currently live on testnet. Whether you're a developer that just wants to start building or you're curious into digging deeper into the internals of Arbitrum and how it works, this site is the right place for you.
How does Arbitrum work?
If you're looking to discover how Arbitrum works, the best place to begin is by the Rollups basics section, which gives a high level overview of Arbitrum's internals. From there, you can jump into more detailed explainers on various components of the system.
How Can I Start Building
If you want to get started using Arbitrum with no setup required, check out our public testnet running on top of Kovan.
How Can I Develop Locally
The very first step to start building with Arbitrum is installing Arbitrum and its dependencies. Next, you'll need to deploy an Arbitrum chain on an L1 blockchain. Arbitrum Rollup supports deployment both on a local testnet and on the Rinkeby Testnet. The following quickstart walks through deployment of an Arbitrum Rollup chain on the local testnet.
Note that Arbitrum chains support dynamic launching of contracts, so you don't need to setup an Arbitrum chain for each application you build, and indeed you may deploy your contracts on a testnet chain which you did not launch. The benefits of having multiple applications on the same Arbitrum Rollup chain is that they'll be able to interact synchronously, just as they would if they were launched directly on Ethereum.
Setup Local Geth and Rollup Blockchain
Now you'll deploy and run a demo dApp on Arbitrum. The dApp is based on a simple Pet Shop dApp that is used in a Truffle tutorial.
First clone the pet-shop demo dApp and install dependencies:
git clone https://github.com/OffchainLabs/demo-dapp-pet-shop cd demo-dapp-pet-shop yarn
Deploy contracts to Arbitrum :
truffle migrate --network arbitrum
Use the dApp
Once Metamask is installed, open it and select
Import Accountand enter one of the following pre-funded private keys
0x979f020f6f6f71577c09db93ba944c89945f10fade64cfc7eb26137d5816fb76 0xd26a199ae5b6bed1992439d1840f7cb400d0a55a0c9f796fa67d7c571fbb180e 0xaf5c2984cb1e2f668ae3fd5bbfe0471f68417efd012493538dcd42692299155b 0x9af1e691e3db692cc9cad4e87b6490e099eb291e3b434a0d3f014dfd2bb747cc 0x27e926925fb5903ee038c894d9880f74d3dd6518e23ab5e5651de93327c7dffa 0xe4b33c0bb790b88f2463facaf86ae7c17cbdab41187e69ddde8cc1c1fda7c9ab
Select local arbitrum network in Metamask
- Go back to Metamask or click the extension icon
Main Ethereum Networktop right hand side
Local Arbitrumas the network name
http://127.0.0.1:8547as the RPC url
- Press the save button
- Metamask should now have an Local Arbitrum account holding ETH
Launch the front-end
The browser will open to localhost:8080
In the popup window that appears, select
Adopt some pets
The pet shop dApp should now be running in your browser. Choose a pet or two and click the adopt button to adopt your new animal friend(s).
If you want to try another dApp run, deploy the solidity contracts and launch the frontend
git clone https://github.com/OffchainLabs/demo-dapp-election cd demo-dapp-election yarn truffle migrate --network arbitrum yarn start