Miden ⇄ EVM Epoch Integration Example

Reference dapp showing how to use @epoch-protocol/epoch-intents-sdk to move value between Epoch testnet EVM chains and Miden devnet or testnet via Epoch intents.

Two flows:

• Cross-chain — Miden → EVM. Lock a Miden note, receive tokens on the selected EVM testnet chain.
• Withdraw — EVM → Miden. Pay ERC-20 on a connected EVM testnet chain, receive a Miden note.

Supported testnet chains

Network	Chain ID
Ethereum Sepolia	11155111
Base Sepolia	84532
Optimism Sepolia	11155420
Miden (virtual)	999999999

Testnet tokens (USDC, DAI, USDT, etc.) share the same contract addresses across all EVM testnet chains. See Supported Chains & Tokens.

Stack

• React 19 + Vite + TypeScript + Tailwind v4
• EVM: wagmi + RainbowKit + viem
• Miden: @miden-sdk/miden-sdk, @miden-sdk/miden-wallet-adapter-react
• Intents: @epoch-protocol/epoch-intents-sdk against the Epoch testnet allocator

Run Locally

1. Install + start:

   pnpm i
   pnpm run dev

2. Open http://localhost:5173.

Wallets

• EVM: any RainbowKit-supported wallet (MetaMask etc.) on an Epoch testnet EVM chain. Pays gas + provides tokens for withdraw deposits.
• Miden: Miden wallet adapter. Required for Withdraw and for creating P2IDE notes in Cross-chain.

Test Funds

• Miden testnet tokens: claim from a configured testnet faucet in a testnet Miden wallet.
• EVM testnet tokens: ping Epoch team with your Ethereum address; team will send testnet USDC.

Key Files

Path	Purpose
src/services/epoch-bridge.ts	Epoch SDK wrapper (intent build / submit / poll)
src/hooks/useEpochIntent.ts	Miden→EVM intent submission flow
src/hooks/useWithdrawIntent.ts	EVM→Miden withdraw flow
src/hooks/useMidenWalletAdapter.ts	Miden wallet connect/state
src/hooks/useMidenP2IDNoteFactory.ts	Wallet-submitted P2IDE collateral-note creation
src/hooks/useIntentFlowStatus.ts	Intent lifecycle polling
src/constants/chains.ts	Testnet EVM chains + Miden virtual chain id (999999999)
src/config/wagmi.ts	wagmi/RainbowKit config

Notes

• MIDEN_DESTINATION_CHAIN_ID = 999999999 is the virtual chain id used as tokenOut.chainId when Miden is the intent output. Do not set this to a real EVM chain id.
• The app uses Miden testnet and the Epoch testnet allocator by default. Set VITE_MIDEN_RPC_URL only to override the Miden RPC URL.
• Build: pnpm build (tsc -b && vite build). Lint: pnpm lint.