# Kryard — keys you never touch.

Kryard is wallet infrastructure for gasless, sponsored transactions: a
**Turnkey-wire-compatible signer** and a **managed EIP-7702 relay**. A user signs a
7702 authorization and a batch digest; Kryard signs, fronts gas, and broadcasts the
type-4 transaction. Users never hold gas — and can even pay it in any ERC-20 token.
Live on Sepolia.

## What it is — a drop-in Turnkey replacement

Kryard exposes the exact Turnkey API surface — same endpoint paths, activity
envelope, and X-Stamp auth — over a KMS-encrypted key store and an isolated signer.
Cutover is a single environment-variable swap, with zero client changes:

```sh
# Before
TURNKEY_BASE_URL=https://api.turnkey.com

# After — zero client changes
TURNKEY_BASE_URL=https://api.kryard.com
```

## What you get

- **Managed EIP-7702 relay.** A user signs a 7702 authorization plus a batch digest;
  Kryard signs, fronts gas, and broadcasts the type-4 transaction. Smart-wallet UX
  with no ERC-4337 bundler.
- **Pay gas in any token.** Users settle gas in any ERC-20. The on-chain
  `KryardDelegate` reimburses the relayer an exact, user-signed fee that can't be
  inflated.
- **Turnkey-wire-compatible.** A drop-in replacement for Turnkey's secp256k1 EVM
  signing — cutover is a single `TURNKEY_BASE_URL` swap.
- **Thin, dependency-light SDK.** `@kryard/sdk` — `signAuthorization` → sponsored
  `execute`. Built-in MIT X-Stamp signer, `viem` peer dependency, on npm and GitHub.

## Three security invariants

- **The API never decrypts keys.** Only the isolated signer can call KMS decrypt;
  envelope encryption with a verified encryption context.
- **Every operation is an immutable activity.** Activities are the unit of work,
  idempotency, and audit (SHA-256 of the canonical JSON body).
- **Signing is bound to activity + policy.** The signer refuses any payload that
  doesn't match the recorded policy decision.

## Start

- Install the CLI: `curl -fsSL https://kryard.com/install.sh | sh`
- Docs & quickstart: <https://docs.kryard.com/>
- SDK on npm: <https://www.npmjs.com/package/@kryard/sdk>
- Source: <https://github.com/Kryard>

## Common questions

- **Is it a Turnkey alternative?** Yes — wire-compatible; migrate with one env-var swap.
- **Does it need a 4337 bundler?** No — it uses a managed EIP-7702 relay.
- **Is it self-custodial?** Keys are KMS-encrypted and never leave the isolated
  signer; the relay only signs what the user authorized with their 7702 signature.
- **Which chains?** EVM; live on Sepolia and other testnets (Base, Arbitrum,
  Optimism, Polygon, BSC).