# How to use a DFNS signer with permissionless.js

[Dfns](https://www.dfns.co/) is an MPC/TSS Wallet-as-a-Service API/SDK provider. Dfns aims to optimize the balance of security and UX by deploying key shares into a decentralized network on the backend while enabling wallet access via biometric open standards on the frontend like Webauthn. Reach out [here](https://www.dfns.co/) to set up a sandbox environment to get started.

## Setup

To use Dfns with permissionless.js, first create an application that integrates with Dfns.

* Refer to the [Dfns documentation site](https://docs.dfns.co/d/) for instructions on setting up an application with the Dfns.

## Integration

Integrating permissionless.js with Dfns is straightforward after setting up the project. Dfns provides an Externally Owned Account (EOA) wallet to use as a signer with permissionless.js accounts.

### Set up Dfns

After following the Dfns documentation, you will have access to a `dfnsWallet` object as shown below:

```typescript
import { DfnsWallet } from "@dfns/lib-viem"
import { DfnsApiClient } from "@dfns/sdk"
import { AsymmetricKeySigner } from "@dfns/sdk-keysigner"
import { AccountSource, createWalletClient, http } from "viem"
import { toAccount } from "viem/accounts"

const initDfnsWallet = (walletId: string) => {
	const signer = new AsymmetricKeySigner({
		privateKey: DFNS_PRIVATE_KEY,
		credId: DFNS_CRED_ID,
		appOrigin: DFNS_APP_ORIGIN,
	})

	const dfnsClient = new DfnsApiClient({
		appId: DFNS_APP_ID,
		authToken: DFNS_AUTH_TOKEN,
		baseUrl: DFNS_API_URL,
		signer,
	})

	return DfnsWallet.init({
		walletId,
		dfnsClient,
		maxRetries: 10,
	})
}

const sepoliaWallet = await initDfnsWallet(SEPOLIA_WALLET_ID)
const account = toAccount(sepoliaWallet as AccountSource)
const smartAccountOwner = createWalletClient({
	account,
	transport: http("https://sepolia.rpc.thirdweb.com"),
})
```

### Use with permissionless.js

:::code-group
```ts [SimpleAccount]
import { createSmartAccountClient } from "permissionless"
import { toSimpleSmartAccount } from "permissionless/accounts"
import { createPublicClient, http } from "viem"
import { sepolia } from "viem/chains"
import { createPimlicoClient } from "permissionless/clients/pimlico"
import { entryPoint07Address } from "viem/account-abstraction"

const publicClient = createPublicClient({
	chain: sepolia, // or whatever chain you are using
	transport: http(),
})

const pimlicoUrl = `https://api.pimlico.io/v2/sepolia/rpc?apikey=<PIMLICO_API_KEY>`

const pimlicoClient = createPimlicoClient({
	transport: http(pimlicoUrl),
	entryPoint: {
		address: entryPoint07Address,
		version: "0.7",
	},
})

const simpleSmartAccount = await toSimpleSmartAccount({
	owner: smartAccountOwner,
	client: publicClient,
	entryPoint: {
		address: entryPoint07Address,
		version: "0.7",
	},
})

const smartAccountClient = createSmartAccountClient({
	account: simpleSmartAccount,
	chain: sepolia,
	bundlerTransport: http(pimlicoUrl),
	paymaster: pimlicoClient,
	userOperation: {
		estimateFeesPerGas: async () => {
			return (await pimlicoClient.getUserOperationGasPrice()).fast
		},
	},
})
```

```ts [Safe Account]
import { createSmartAccountClient } from "permissionless"
import { toSafeSmartAccount } from "permissionless/accounts"
import { createPublicClient, http } from "viem"
import { sepolia } from "viem/chains"
import { createPimlicoClient } from "permissionless/clients/pimlico"
import { entryPoint07Address } from "viem/account-abstraction"

const publicClient = createPublicClient({
	chain: sepolia, // or whatever chain you are using
	transport: http(),
})

const pimlicoUrl = `https://api.pimlico.io/v2/sepolia/rpc?apikey=<PIMLICO_API_KEY>`

const pimlicoClient = createPimlicoClient({
	transport: http(pimlicoUrl),
	entryPoint: {
		address: entryPoint07Address,
		version: "0.7",
	},
})

const simpleSmartAccount = await toSafeSmartAccount({
	owners: [smartAccountOwner],
	client: publicClient,
	entryPoint: {
		address: entryPoint07Address,
		version: "0.7",
	},
	version: "1.4.1",
})

const smartAccountClient = createSmartAccountClient({
	account: simpleSmartAccount,
	chain: sepolia,
	bundlerTransport: http(pimlicoUrl),
	paymaster: pimlicoClient,
	userOperation: {
		estimateFeesPerGas: async () => {
			return (await pimlicoClient.getUserOperationGasPrice()).fast
		},
	},
})
```

```ts [Kernel Account]
import { createSmartAccountClient } from "permissionless"
import { createPublicClient, http } from "viem"
import { sepolia } from "viem/chains"
import { createPimlicoClient } from "permissionless/clients/pimlico"
import { entryPoint07Address } from "viem/account-abstraction"
import { toKernelSmartAccount } from "permissionless/accounts"

const publicClient = createPublicClient({
	chain: sepolia, // or whatever chain you are using
	transport: http(),
})

const pimlicoUrl = `https://api.pimlico.io/v2/sepolia/rpc?apikey=<PIMLICO_API_KEY>`

const pimlicoClient = createPimlicoClient({
	transport: http(pimlicoUrl),
	entryPoint: {
		address: entryPoint07Address,
		version: "0.7",
	},
})

const simpleSmartAccount = await toKernelSmartAccount({
	owners: [smartAccountOwner],
	client: publicClient,
	entryPoint: {
		address: entryPoint07Address,
		version: "0.7",
	},
})

const smartAccountClient = createSmartAccountClient({
	account: simpleSmartAccount,
	chain: sepolia,
	bundlerTransport: http(pimlicoUrl),
	paymaster: pimlicoClient,
	userOperation: {
		estimateFeesPerGas: async () => {
			return (await pimlicoClient.getUserOperationGasPrice()).fast
		},
	},
})
```

```ts [Biconomy Account]
import { createSmartAccountClient } from "permissionless"
import { toBiconomySmartAccount } from "permissionless/accounts"
import { createPublicClient, http } from "viem"
import { sepolia } from "viem/chains"
import { createPimlicoClient } from "permissionless/clients/pimlico"
import { entryPoint07Address } from "viem/account-abstraction"

const publicClient = createPublicClient({
	chain: sepolia, // or whatever chain you are using
	transport: http(),
})

const pimlicoUrl = `https://api.pimlico.io/v2/sepolia/rpc?apikey=<PIMLICO_API_KEY>`

const pimlicoClient = createPimlicoClient({
	transport: http(pimlicoUrl),
	entryPoint: {
		address: entryPoint07Address,
		version: "0.7",
	},
})

const simpleSmartAccount = await toBiconomySmartAccount({
	owners: [smartAccountOwner],
	client: publicClient,
})

const smartAccountClient = createSmartAccountClient({
	account: simpleSmartAccount,
	chain: sepolia,
	bundlerTransport: http(pimlicoUrl),
	paymaster: pimlicoClient,
	userOperation: {
		estimateFeesPerGas: async () => {
			return (await pimlicoClient.getUserOperationGasPrice()).fast
		},
	},
})
```

```ts [TrustWallet Account]
import { createSmartAccountClient } from "permissionless"
import { toTrustSmartAccount } from "permissionless/accounts"
import { createPublicClient, http } from "viem"
import { sepolia } from "viem/chains"
import { createPimlicoClient } from "permissionless/clients/pimlico"
import { entryPoint07Address } from "viem/account-abstraction"

const publicClient = createPublicClient({
	chain: sepolia, // or whatever chain you are using
	transport: http(),
})

const pimlicoUrl = `https://api.pimlico.io/v2/sepolia/rpc?apikey=<PIMLICO_API_KEY>`

const pimlicoClient = createPimlicoClient({
	transport: http(pimlicoUrl),
	entryPoint: {
		address: entryPoint07Address,
		version: "0.7",
	},
})

const simpleSmartAccount = await toTrustSmartAccount({
	owner: smartAccountOwner,
	client: publicClient,
})

const smartAccountClient = createSmartAccountClient({
	account: simpleSmartAccount,
	chain: sepolia,
	bundlerTransport: http(pimlicoUrl),
	paymaster: pimlicoClient,
	userOperation: {
		estimateFeesPerGas: async () => {
			return (await pimlicoClient.getUserOperationGasPrice()).fast
		},
	},
})
```
:::