---
title: Kryard FAQ — gasless transactions, EIP-7702 relay, Turnkey compatibility
description: Answers to common questions about Kryard — is it a Turnkey alternative, does it need a 4337 bundler, can users pay gas in any token, is it self-custodial, which chains are supported, and how to get started.
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    - type: application/ld+json
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          { "@type": "Question", "name": "What is Kryard?", "acceptedAnswer": { "@type": "Answer", "text": "Kryard is wallet infrastructure for gasless, sponsored transactions: a Turnkey-wire-compatible EVM signer and a managed EIP-7702 relay. A user signs a 7702 authorization and a batch digest, and Kryard signs, fronts gas, and broadcasts the type-4 transaction." } },
          { "@type": "Question", "name": "Is Kryard a Turnkey alternative?", "acceptedAnswer": { "@type": "Answer", "text": "Yes. Kryard exposes the exact Turnkey API surface — same endpoint paths, activity envelope, and X-Stamp auth. Migrating the signing side is a single TURNKEY_BASE_URL swap with zero client changes, and you additionally get a managed EIP-7702 relay and pay-gas-in-any-token." } },
          { "@type": "Question", "name": "Does Kryard need an ERC-4337 bundler?", "acceptedAnswer": { "@type": "Answer", "text": "No. Kryard uses a managed EIP-7702 relay: the user signs a 7702 authorization plus a batch digest and Kryard broadcasts a type-4 transaction. There is no bundler to run and no smart-contract wallet to deploy. Kryard also offers a 4337 verifying-paymaster lane for teams that want the UserOp model." } },
          { "@type": "Question", "name": "Can users pay gas in any token?", "acceptedAnswer": { "@type": "Answer", "text": "Yes. Users can settle gas in any ERC-20. The on-chain KryardDelegate reimburses the relayer an exact, user-signed fee that cannot be inflated." } },
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          { "@type": "Question", "name": "Does Kryard work with viem?", "acceptedAnswer": { "@type": "Answer", "text": "Yes. The @kryard/sdk has viem as a peer dependency and ships a built-in MIT X-Stamp signer, so no external signing SDK is required." } },
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---

# FAQ

## What is Kryard?

Kryard is wallet infrastructure for **gasless, sponsored transactions**: a
**Turnkey-wire-compatible EVM signer** and a **managed EIP-7702 relay**. A user signs
a 7702 authorization and a batch digest, and Kryard signs, fronts gas, and broadcasts
the type-4 transaction.

## Is Kryard a Turnkey alternative?

Yes. Kryard exposes the **exact Turnkey API surface** — same endpoint paths, activity
envelope, and `X-Stamp` auth. Migrating the signing side is a single
`TURNKEY_BASE_URL` swap with zero client changes, and you additionally get a managed
EIP-7702 relay and pay-gas-in-any-token. See [Kryard vs Turnkey](/compare/turnkey).

## Does Kryard need an ERC-4337 bundler?

No. Kryard uses a **managed EIP-7702 relay** — the user signs a 7702 authorization
plus a batch digest and Kryard broadcasts a **type-4** transaction. There's no
bundler to run and no smart-contract wallet to deploy. (Kryard also offers a 4337
verifying-paymaster lane for teams that want the UserOp model.) See
[7702 vs 4337](/concepts/7702-vs-4337).

## Can users pay gas in any token?

Yes. Users settle gas in **any ERC-20**. The on-chain `KryardDelegate` reimburses the
relayer an **exact, user-signed** fee that can't be inflated. See
[Pay gas in any token](/relay/erc20-gas).

## Is Kryard self-custodial and secure?

Keys are **KMS envelope-encrypted** and never leave an isolated signer; the API can
never decrypt them. Every sensitive operation is an **immutable, idempotent
activity**, and signing is **bound to the recorded policy decision**. The relay only
signs what the user authorized with their 7702 signature.

## Does Kryard work with viem?

Yes. `@kryard/sdk` has **viem** as a peer dependency and ships a **built-in MIT
X-Stamp signer**, so no external signing SDK is required.

## Which chains does Kryard support?

**EVM** chains. Kryard is live and proven end-to-end on **testnets** — Ethereum
Sepolia, Base Sepolia, Arbitrum Sepolia, Optimism Sepolia, Polygon Amoy, and BSC
testnet. Mainnet is gated behind a hardening milestone.

## How do I get started?

Install the SDK or the CLI, then follow the quickstart:

```bash
npm i @kryard/sdk viem
# or the CLI:
curl -fsSL https://kryard.com/install.sh | sh
```

Then: [Quickstart](/relay/quickstart).