# @multiplatform.one/gpg

Sign-In With GPG (SIWG) for the multiplatform.one connectkit modal — a
connection-free signer where the user signs a challenge in their terminal and
pastes the result back. Pulls in **no wagmi/viem**: it depends only on
`@multiplatform.one/connectkit`, so a GPG-only app can skip the wallet stack.

## Install

```bash
pnpm add @multiplatform.one/gpg @multiplatform.one/connectkit
```

Peers: `react`, `@tanstack/react-query`.

## What it owns

- **`GpgProvider`** — GPG auth state + challenge/nonce lifecycle
  (`GPG_NONCE_QUERY_KEY`)
- **`useGpg()`** — status, sign-in/sign-out actions (`GpgStatusState`)
- **`SignInWithGpg`** / `SignInWithGpgButton` (alias `GPGButton`) — drop-in
  sign-in surface and trigger button
- **`gpgScreen`**, `GpgScreenRegistrar`, `GpgBridge` — registers the GPG
  screen into the connectkit modal's screen registry

## What it must not do

- No blockchain wallets, no viem/wagmi — wallet signers live in
  `@multiplatform.one/web3`
- No modal shell of its own — it registers screens into
  `@multiplatform.one/connectkit`

## Usage

```tsx
import { ConnectKitProvider } from "@multiplatform.one/connectkit";
import { GpgBridge, GpgProvider, SignInWithGpgButton } from "@multiplatform.one/gpg";

export function App() {
  return (
    <GpgProvider getNonce={getNonce} onSign={onSign} buildMessage={buildMessage}>
      <ConnectKitProvider bridge={GpgBridge}>
        <SignInWithGpgButton />
      </ConnectKitProvider>
    </GpgProvider>
  );
}
```

`buildMessage` is the challenge the user signs; this package has no builder of
its own. Pass `buildWalletMessage("gpg", { nonce })` from
`@multiplatform.one/web3/message`, or use web3's `GpgProvider`, which defaults
to it. `GpgProvider` must wrap **outside** `ConnectKitProvider`. In an app that also
ships wallets, `@multiplatform.one/web3` mounts `GpgScreenRegistrar` alongside
its own screens instead of `GpgBridge`.

## License

Apache-2.0