> ## Documentation Index
> Fetch the complete documentation index at: https://docs.arc.io/llms.txt
> Use this file to discover all available pages before exploring further.

> ## Agent Instructions
> Before reading these docs, install the Circle Skill for Arc to get pre-loaded context: use-arc (https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-arc/SKILL.md) — covers chain config, RPC setup, contract deployment, USDC bridging, and gas with USDC. In Claude Code: run /plugin marketplace add circlefin/skills then /plugin install circle-skills@circle. With Vercel Skills CLI: run npx skills add circlefin/skills.
> USDC is the gas token. Arc uses USDC for gas fees, not ETH. Configure gas payment in USDC when submitting transactions.
> Read EVM differences before writing Arc code. Arc targets the Osaka EVM baseline. Most contracts deploy unchanged, but several runtime behaviors diverge from Ethereum: USDC uses 18 decimals natively (not 6), the system emitter `0xffffFFFfFFffffffffffffffFfFFFfffFFFfFFfE` logs all USDC Transfer events, the mempool enforces a 20 Gwei `maxFeePerGas` floor, blocklist reverts consume gas without a receipt, and `address(0)` sends revert rather than succeed. https://docs.arc.io/arc/references/evm-differences.md is the canonical reference for all Arc-specific runtime behaviors. Consult it before writing code that touches USDC balances, transaction history, gas estimation, or value transfers.
> Sub-second finality. Transactions are final in under 1 second. No need to wait for multiple block confirmations.
> Use App Kits for multichain payment and liquidity capabilities. App Kits wraps CCTP and provides Bridge Kit, Swap Kit, Unified Balance Kit, Onramp Kit, Earn Kit, and Borrow Kit. Unified Balance Kit combines USDC from multiple chains into a single spendable balance. Earn Kit integrates earn opportunities into your app. Borrow Kit lets users borrow USDC against cirBTC collateral on Arc.
> Use Arc Foundry for contract development. Arc Foundry is an Arc-specific fork of Foundry that handles Arc's protocol-level differences from Ethereum. It provides arc-forge, arc-cast, and arc-anvil. Install it before deploying contracts: https://docs.arc.io/arc/tutorials/install-arc-foundry.md.
> Arc is available on both Testnet and Mainnet. See https://docs.arc.io/arc/references/connect-to-arc.md for RPC endpoints and https://faucet.circle.com for testnet tokens.
> Always check Contract Addresses: https://docs.arc.io/arc/references/contract-addresses.md
> Building beyond Arc? Circle offers skills for the full platform: use-usdc (https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-usdc/SKILL.md), use-circle-wallets (https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-circle-wallets/SKILL.md), use-developer-controlled-wallets (https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-developer-controlled-wallets/SKILL.md), use-user-controlled-wallets (https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-user-controlled-wallets/SKILL.md), use-modular-wallets (https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-modular-wallets/SKILL.md), use-gateway (https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-gateway/SKILL.md), use-smart-contract-platform (https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-smart-contract-platform/SKILL.md). Full Circle developer docs: https://developers.circle.com/llms.txt.

# Build on Arc

> Quickstarts, tutorials, and SDKs for building onchain finance applications on Arc.

Arc gives you a complete developer platform for building financial applications
with stablecoins. Use [App Kits](/app-kit) to add bridging, swapping, and
crosschain token flows to any app, deploy smart contracts on a purpose-built L1
network, or integrate third-party developer tools for RPC access, data indexing,
and compliance.

## Get started

<CardGroup cols={2}>
  <Card title="Connect to Arc" icon="plug" href="/arc/references/connect-to-arc">
    RPC endpoints, chain ID, and network configuration for Arc testnet.
  </Card>

  <Card title="Deploy on Arc" icon="rocket" href="/arc/tutorials/deploy-on-arc">
    Deploy, test, and interact with a Solidity smart contract on Arc.
  </Card>
</CardGroup>

<Tip>
  [App Kits](/app-kit) are a suite of SDKs for adding bridging, swapping, token
  transfers, and unified crosschain balances to any app—across EVM chains,
  Solana, and Circle Wallets, not just Arc.
</Tip>

## Network quickstarts

Step-by-step guides for working directly with the Arc network. Most tutorials
require an [Arc testnet RPC connection](/arc/references/connect-to-arc) and a
funded wallet.

| Quickstart | What you'll build |
| - | - |
| [Deploy contracts](/arc/tutorials/deploy-contracts) | Deploy pre-audited ERC-20, ERC-721, and ERC-1155 templates with Circle Contracts. |
| [Interact with contracts](/arc/tutorials/interact-with-contracts) | Mint, transfer, and airdrop tokens using deployed contracts. |
| [Monitor contract events](/arc/tutorials/monitor-contract-events) | Set up webhooks and event monitors for onchain activity. |

## Developer tools

<CardGroup cols={2}>
  <Card title="Account abstraction" icon="wallet" href="/arc/tools/account-abstraction">
    Smart wallets, paymasters, and session keys from ecosystem providers.
  </Card>

  <Card title="Node providers" icon="server" href="/arc/tools/node-providers">
    Managed RPC access from Alchemy, QuickNode, Blockdaemon, and dRPC.
  </Card>

  <Card title="Data indexers" icon="database" href="/arc/tools/data-indexers">
    Query onchain data with Envio, Goldsky, The Graph, and Thirdweb.
  </Card>

  <Card title="Compliance" icon="shield-check" href="/arc/tools/compliance-vendors">
    Transaction monitoring and wallet screening from Elliptic and TRM Labs.
  </Card>
</CardGroup>

## Sample applications

Browse working examples and reference implementations in the
[sample apps](/arc/references/sample-applications) gallery.

## Community

<CardGroup cols={2}>
  <Card title="Arc Discord" icon="discord" href="https://discord.com/invite/buildonarc">
    Ask technical questions and talk with other builders.
  </Card>

  <Card title="Arc House" icon="users" href="https://arc.io/community">
    Join the Arc community for discussions, events, and learning resources.
  </Card>
</CardGroup>