Skip to main content
SELAT Router SDK supports three signer patterns. Pick the simplest one that matches your security model.

​
Private key signer

Use this when you need the fastest path to get started and the private key is acceptable in-process. 
import { RouterClient, createViemSigner } from "@selat-ai/router-client";

const signer = createViemSigner(process.env.X402_CLIENT_PRIVATE_KEY as `0x${string}`);

const client = new RouterClient({
  chain: "base",
  signer
});

​
Circle Agent Wallet signer

Use this when you want the signer to stay outside the SDK process and you already manage a Circle Agent Wallet. 
import { RouterClient, createCircleAgentWalletSigner } from "@selat-ai/router-client";

const signer = createCircleAgentWalletSigner({
  address: process.env.SELAT_SIGNER_ADDRESS as `0x${string}`,
  chain: "base"
});

const client = new RouterClient({
  chain: "base",
  signer
});
This is the recommended option for production when you want to keep keys out of the application runtime.

​
Remote signer

Use this when signing happens in a wallet service, HSM, or KMS. 
import { RouterClient, createRemoteSigner } from "@selat-ai/router-client";

const signer = createRemoteSigner(
  "0x1111111111111111111111111111111111111111",
  async ({ address, typedData }) => {
    const response = await fetch("https://signer.example.com/sign-typed-data", {
      method: "POST",
      headers: { "content-type": "application/json" },
      body: JSON.stringify({ address, typedData })
    });

    const data = await response.json() as { signature: `0x${string}` };
    return data.signature;
  }
);

​
Choosing a signer

  • Use a private key for the quickest prototype.
  • Use Circle Agent Wallets for production when the wallet should remain outside the SDK process.
  • Use a remote signer when your org already centralizes signing in a separate service.