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

# Account models

> Classic G-addresses vs. passkey smart-contract accounts - when to use each.

Buckspay separates *who signs* (`BuckspaySigner`) from *what account signs* (`AccountAdapter`).
They are **orthogonal**: you can pair any signer with any account type. The two account models
ship in v1.

## Comparison

|                       | Classic                                       | Passkey / contract                        |
| --------------------- | --------------------------------------------- | ----------------------------------------- |
| User prerequisite     | A Stellar wallet (Freighter / xBull / LOBSTR) | A device with WebAuthn support            |
| Address               | `G...` account                                | `C...` contract account                   |
| Materialization       | Sponsored onboarding (account + trustline)    | Sponsored OZ Smart Account deploy         |
| Signature verified by | The network (Ed25519)                         | The contract's `__check_auth` (secp256r1) |
| Best for              | Existing Stellar users                        | New users and passwordless onboarding     |

## Classic account (`G...`)

For users who already have a Stellar wallet (Freighter, xBull, LOBSTR). Calling `connect()`
resolves the `G...` address and runs sponsored onboarding - it creates the account and adds the
USDC trustline - if either is missing.

The network verifies the user's signature via standard Ed25519 authentication. No contract is
involved.

The `classicAccount()` adapter is imported from `@buckspay/accounts/classic`; the matching
signer is `walletsKit` from `@buckspay/signers/wallets-kit`.

```ts theme={null}
// Recipe A - classic wallet account (G...), for users who already have a Stellar wallet.
import { createBuckspayClient, createRpcSimContext, type BuckspayConfig } from "@buckspay/core";
import { classicAccount } from "@buckspay/accounts/classic";
import { walletsKit } from "@buckspay/signers/wallets-kit";
import { buckspayFacilitator } from "@buckspay/relayer/buckspay-facilitator";

export const classicConfig: BuckspayConfig = {
  network: "testnet",
  account: classicAccount(),
  signer: walletsKit({ network: "testnet" }),
  relayer: buckspayFacilitator({ url: "/api/gasless", network: "testnet" }),
  gas: { mode: "sponsored" }
};

// connect() resolves the G... address and runs sponsored onboarding (account + USDC trustline) if missing.
export const classicClient = createBuckspayClient(
  classicConfig,
  createRpcSimContext("https://soroban-testnet.stellar.org")
);
```

## Passkey / contract account (`C...`)

The hero flow for new users. `connect()` creates a WebAuthn credential, derives the
deterministic `C...` address, and deploys the OpenZeppelin Smart Account **sponsored** by the
facilitator. The user only taps an authenticator prompt - no seed phrase, no XLM balance
required.

Signing happens in the device authenticator (secp256r1). The contract's `__check_auth`
verifies the signature on-chain. See [Gasless on Stellar](/concepts/gasless-on-stellar) for
the mechanics.

The `ozContractAccount()` adapter is imported from `@buckspay/accounts/oz-contract`;
`sponsorAddress` is the facilitator's public sponsor `G...` address, needed to derive the `C...`
address offline.

```ts theme={null}
// Recipe B - passkey smart account (C...), the hero flow. Browser only (uses window).
import { createBuckspayClient, createRpcSimContext, type BuckspayConfig } from "@buckspay/core";
import { ozContractAccount } from "@buckspay/accounts/oz-contract";
import { passkey } from "@buckspay/signers/passkey";
import { buckspayFacilitator } from "@buckspay/relayer/buckspay-facilitator";

// Public facilitator sponsor/deployer G-address (derives the deterministic C-address).
const SPONSOR_G: string = "GA5ZSEJYB37JRC5AVCIA5MOP4RHTM335X2KGX3IHOJAPP5RE34K4KZVN";

export const passkeyConfig: BuckspayConfig = {
  network: "testnet",
  account: ozContractAccount({ network: "testnet", sponsorAddress: SPONSOR_G }),
  // create()s a passkey, derives the C-address, deploys the OZ Smart Account sponsored.
  signer: passkey({ rpId: window.location.hostname, rpName: "buckspay" }),
  relayer: buckspayFacilitator({ url: "/api/gasless", network: "testnet" }),
  gas: { mode: "sponsored" }
};

export const passkeyClient = createBuckspayClient(
  passkeyConfig,
  createRpcSimContext("https://soroban-testnet.stellar.org")
);
```

## The `AccountAdapter` seam

`AccountAdapter` is the interface both models implement. OZ Smart Accounts is the only
contract implementation in v1, but the interface is open - you can wire in any conforming
adapter without changing the rest of the client.

## Next

<CardGroup cols={2}>
  <Card title="Prepare -> Sign -> Send" href="/concepts/prepare-sign-send">
    The three-phase flow every Buckspay payment follows.
  </Card>

  <Card title="Gasless on Stellar" href="/concepts/gasless-on-stellar">
    The native Stellar mechanisms behind sponsored and contract accounts.
  </Card>
</CardGroup>