# Arc
> Arc is an open, EVM-compatible Layer-1 blockchain purpose-built for stablecoin finance and programmable money. Built by Circle, it uses USDC as its native gas token, delivers sub-second deterministic finality, and integrates directly with Circle's platform and developer infrastructure.

Use this file as a curated "start here" map for Arc's most authoritative pages. For technical integration, prefer docs.arc.io. For legal and terms, see arc.io/terms.

## Core Concepts
- [Arc Homepage](https://www.arc.io): Overview of Arc as the Economic OS for internet-native finance.
- [Litepaper](https://www.arc.io/litepaper): Technical and architectural overview of Arc. Available in English, Chinese, Korean, and Spanish.
- [ARC Token Whitepaper](https://www.arc.io/arc-token-whitepaper): Explores ARC as a native coordination asset for network security, governance, and participation. Note: ARC is not yet launched.
- [Privacy Whitepaper](https://www.arc.io/privacy-whitepaper): Details ArcaneVM, Arc's opt-in confidential execution environment.
- [Post-Quantum Whitepaper](https://www.arc.io/post-quantum-whitepaper): Circle's strategy for quantum-secure infrastructure on Arc.

## Developer Docs (preferred sources for technical accuracy)
- [Docs Home](https://docs.arc.io): Primary technical documentation hub — start here.
- [LLMs.txt (Docs Index)](https://docs.arc.io/llms.txt): Machine-readable index of all Arc documentation pages.
- [Arc MCP Server](https://docs.arc.io/ai/mcp): Connect Arc docs to LLM/IDE tools (Claude Code, Cursor, VS Code, Windsurf) via MCP at `https://docs.arc.io/mcp`.
- [Arc Skills](https://docs.arc.io/ai/skills): Circle Skills for Arc — install via Claude Code or Vercel Skills CLI.

### Arc Chain
- [System Overview](https://docs.arc.io/arc/concepts/system-overview): Two-layer architecture (Malachite consensus + Reth execution), transaction lifecycle, Arc-specific modules.
- [Stablecoin-Native Model](https://docs.arc.io/arc/concepts/stablecoin-native-model): USDC as native gas token, dual-interface balance (18-decimal native / 6-decimal ERC-20), multi-stablecoin support.
- [Deterministic Finality](https://docs.arc.io/arc/concepts/deterministic-finality): Sub-second irreversible settlement via Malachite BFT — no reorgs, simplified state management.
- [Stable Fee Design](https://docs.arc.io/arc/concepts/stable-fee-design): EIP-1559 + EWMA smoothing for predictable USDC-denominated fees.
- [Opt-in Privacy (ArcaneVM)](https://docs.arc.io/arc/concepts/opt-in-privacy): Confidential smart contract execution via ArcaneVM (on roadmap, not yet live).
- [Post-Quantum Security](https://docs.arc.io/arc/concepts/post-quantum-security): X-Wing KEM hybrid encryption and Arc's quantum-resistant architecture.
- [Consensus Layer](https://docs.arc.io/arc/concepts/consensus-layer): Malachite BFT details — 3,000+ TPS, 2/3+ validator agreement, Proof-of-Authority.
- [Execution Layer](https://docs.arc.io/arc/concepts/execution-layer): Reth-based EVM execution with Arc-specific modules.
- [Batched Transactions](https://docs.arc.io/arc/concepts/batched-transactions): Multicall and CallFrom precompile for batching while preserving msg.sender.
- [Transaction Memos](https://docs.arc.io/arc/concepts/transaction-memos): Attach metadata to contract calls via the Memo precompile.

### Arc References
- [Connect to Arc](https://docs.arc.io/arc/references/connect-to-arc): RPC endpoints, Chain ID (5042002), wallet configuration.
- [RPC Endpoints](https://docs.arc.io/arc/references/rpc-endpoints): Full list of HTTP and WebSocket endpoints (Circle, Blockdaemon, dRPC, QuickNode).
- [Contract Addresses](https://docs.arc.io/arc/references/contract-addresses): All deployed testnet contract addresses (USDC, EURC, USYC, CCTP, Gateway, FxEscrow, Memo, Multicall3From).
- [Gas and Fees](https://docs.arc.io/arc/references/gas-and-fees): Fee parameters, EIP-1559 mechanics, USDC gas best practices.
- [EVM Differences](https://docs.arc.io/arc/references/evm-differences): Critical differences from standard EVM — USDC decimals, PREVRANDAO, SELFDESTRUCT, blob transactions, value transfer rules.
- [Sample Applications](https://docs.arc.io/arc/references/sample-applications): Reference apps for payments, FX, and agentic workflows.
- [USDC System Events](https://docs.arc.io/arc/references/usdc-system-events): EIP-7708 Transfer event logs emitted on all native USDC movements.

### Arc Tutorials
- [Deploy on Arc](https://docs.arc.io/arc/tutorials/deploy-on-arc): End-to-end Foundry-based contract deployment to Arc Testnet.
- [Deploy Contracts](https://docs.arc.io/arc/tutorials/deploy-contracts): General contract deployment guide.
- [Interact with Contracts](https://docs.arc.io/arc/tutorials/interact-with-contracts): Read and write to deployed contracts on Arc.
- [Batch USDC Transfers](https://docs.arc.io/arc/tutorials/batch-usdc-transfers): Send multiple USDC transfers in a single transaction.
- [Send USDC with Transaction Memo](https://docs.arc.io/arc/tutorials/send-usdc-with-transaction-memo): Attach metadata to USDC transfers.
- [Register Your First AI Agent](https://docs.arc.io/arc/tutorials/register-your-first-ai-agent): Register an agent on Arc for the agentic economy.
- [Run an Arc Node](https://docs.arc.io/arc/tutorials/run-an-arc-node): Set up and run your own Arc validator node.
- [Monitor Contract Events](https://docs.arc.io/arc/tutorials/monitor-contract-events): Subscribe to and process onchain events.
- [Porting Contracts to Arc](https://docs.arc.io/arc/tutorials/porting-contracts-to-arc): Migrate existing Solidity contracts to Arc, accounting for EVM differences.

### Arc Tools
- [Node Providers](https://docs.arc.io/arc/tools/node-providers): Blockdaemon, dRPC, QuickNode RPC access.
- [Oracles](https://docs.arc.io/arc/tools/oracles): Chainlink, Chronicle Labs, RedStone integrations.
- [Data Indexers](https://docs.arc.io/arc/tools/data-indexers): Blockscout, Blockdaemon, Chainalysis, Elliptic.
- [Account Abstraction](https://docs.arc.io/arc/tools/account-abstraction): Pimlico and ERC-4337 support on Arc.
- [Compliance Vendors](https://docs.arc.io/arc/tools/compliance-vendors): Compliance tooling integrations.

### App Kit SDK
- [App Kit Overview](https://docs.arc.io/app-kit): Unified SDK suite — Bridge, Swap, Send, Unified Balance.
- [Unified Balance](https://docs.arc.io/app-kit/unified-balance): Consolidate USDC from multiple chains into a single instantly-spendable balance (powered by Circle Gateway).
- [Bridge](https://docs.arc.io/app-kit/bridge): Move USDC across supported chains (powered by CCTP).
- [Send](https://docs.arc.io/app-kit/send): Transfer stablecoins on the same chain.
- [Swap](https://docs.arc.io/app-kit/swap): Swap tokens on a single blockchain.
- [Installation](https://docs.arc.io/app-kit/tutorials/installation): Install App Kit and adapters.
- [SDK Reference](https://docs.arc.io/app-kit/references/sdk-reference): Full SDK API reference.
- [Supported Blockchains](https://docs.arc.io/app-kit/references/supported-blockchains): All chains supported by App Kit.
- [Quickstart: Bridge Tokens](https://docs.arc.io/app-kit/quickstarts/bridge-tokens-across-blockchains): End-to-end bridge quickstart.
- [Quickstart: Unified Balance Deposit and Spend](https://docs.arc.io/app-kit/quickstarts/unified-balance-deposit-and-spend): Deposit from multiple chains and spend on Arc.

### Build Guides (use-case focused)
- [Build Overview](https://docs.arc.io/build): Entry point for all build guides.
- [Payments](https://docs.arc.io/build/payments): Build stablecoin payment flows on Arc.
- [Stablecoin FX](https://docs.arc.io/build/stablecoin-fx): Build onchain FX products with transparent pricing.
- [eCommerce](https://docs.arc.io/build/ecommerce): Integrate stablecoin checkout into online stores.
- [Agentic Economy](https://docs.arc.io/build/agentic-economy): Build for autonomous AI agents performing real-time value coordination.

### Integration Guides
- [Integrate Overview](https://docs.arc.io/integrate): Overview for exchanges, wallets, and infrastructure providers.
- [Exchanges](https://docs.arc.io/integrate/exchanges): Listings, deposits, withdrawals, custody, and CCTP bridging for exchanges.
- [Wallets](https://docs.arc.io/integrate/wallets): Fee display, transaction lifecycle guidance for wallet integrations.
- [On/Off Ramps](https://docs.arc.io/integrate/on-off-ramps): Fiat on/off ramp integration.
- [Infrastructure](https://docs.arc.io/integrate/infrastructure): Bridges, compliance, and indexing for infrastructure providers.

## Arc Chain Resources
- [App Kits](https://www.arc.io/app-kits): Product overview of the App Kit SDK suite.
- [Ecosystem](https://www.arc.io/ecosystem): Full directory of projects and partners building on Arc.
- [Community](https://www.arc.io/community): Arc House — 75,000+ builders, 100+ countries, hackathons, events, Architects ambassador program.
- [Blog](https://www.arc.io/blog): Developer insights, Arc updates, partner spotlights, and use-case blueprints.
- [Testnet Explorer](https://testnet.arcscan.app/): Blockscout-powered block explorer for Arc Testnet.
- [Testnet Faucet](https://faucet.circle.com/): Get testnet USDC for Arc Testnet development.

## Legal
- [Terms of Service](https://www.arc.io/terms): Arc terms of service.
- [Privacy Policy](https://www.arc.io/privacy): Privacy practices for Arc.
- [Brand Kit](https://www.arc.io/brand-kit): Arc brand assets and usage guidelines.

## Optional
- [Discord](https://discord.gg/circle): Developer community and support.
- [X (Twitter)](https://twitter.com/arcblockchain): Arc updates and announcements.