Create a Delegated Signer for your Wallet

Give third parties the possibility to transact with your wallet. Always maintain control over what that key can do with tight permissions and being able to revoke them at any time.

Prerequisites

Ensure you have a wallet created.
API Key: Ensure you have an API key with the scopes: wallets:signatures.create and wallets:transactions.create.

Adding a delegated signer

React
Node.js
React Native
REST

import { useWallet } from '@crossmint/client-sdk-react-ui';

const { wallet } = useWallet();

const externalSigner = {
    type: "external-wallet",
    address: "0x1234567890123456789012345678901234567890"
}

await wallet.addDelegatedSigner({
    signer: externalSigner,
});

See the React SDK reference for more details.

import { CrossmintWallets, createCrossmint } from "@crossmint/wallets-sdk";

const crossmint = createCrossmint({
    apiKey: "<your-server-api-key>",
});

const crossmintWallets = CrossmintWallets.from(crossmint);

const wallet = await crossmintWallets.getWallet(
    "email:user@example.com:evm",
    { chain: "base-sepolia", signer: { type: "email" } }
);

const externalSigner = {
    type: "external-wallet",
    address: "0x1234567890123456789012345678901234567890"
}

await wallet.addDelegatedSigner({
    signer: externalSigner,
});

Parameters

signer

string | object

required

The locator of the signer to add.

import { useWallet } from '@crossmint/client-sdk-react-native-ui';

const { wallet } = useWallet();

const externalSigner = {
    type: "external-wallet",
    address: "0x1234567890123456789012345678901234567890"
}

await wallet.addDelegatedSigner({
    signer: externalSigner,
});

See the React Native SDK reference for more details.

Delegated signers must be approved by the wallet’s admin signer. The SDK handles this automatically, but with the REST API you must approve the transaction (if using Solana, Stellar) or signature (if using EVM) to complete it.

Create the delegated signer

Call the create delegated signer endpoint.

curl --request POST \
    --url https://staging.crossmint.com/api/2025-06-09/wallets/email:user@example.com:evm/signers \
    --header 'Content-Type: application/json' \
    --header 'X-API-KEY: <x-api-key>' \
    --data '{
        "chain": "base",
        "signer": "external-wallet:0x1234567890123456789012345678901234567890"
    }'

See the API reference for more details.

Sign the approval returned in the response

If you are using an api-key as the admin signer you can skip the following steps.

Sign the approval message field returned in the response inside transaction.approvals (for EVM) or signature.approvals (for Solana and Stellar) using the admin signer.

Approve the transaction or signature to create the delegated signer

EVM
Solana and Stellar

Call the approve signature endpoint using the signature from the previous step and the signature id returned in the call from Step 1.

curl --request POST \
    --url https://staging.crossmint.com/api/2025-06-09/wallets/email:user@example.com:evm/signatures/b984491a-5785-43c0-8811-45d46fe6e520/approvals \
    --header 'Content-Type: application/json' \
    --header 'X-API-KEY: <x-api-key>' \
    --data '{
        "approvals": [{
            "signer": "email:user@example.com",
            "signature": "0x1234567890abcdef..."
        }]
    }'

See the API reference for more details.

Call the approve transaction endpoint using the signature from the previous step and the transaction id returned in the call from Step 1.

curl --request POST \
    --url https://staging.crossmint.com/api/2025-06-09/wallets/email:user@example.com:solana/transactions/b984491a-5785-43c0-8811-45d46fe6e520/approvals \
    --header 'Content-Type: application/json' \
    --header 'X-API-KEY: <x-api-key>' \
    --data '{
        "approvals": [{
            "signer": "email:user@example.com",
            "signature": "5qY6wXw6zTn7..."
        }]
    }'

See the API reference for more details.

Getting all delegated signers

React
Node.js
React Native
REST

import { useWallet } from '@crossmint/client-sdk-react-ui';

const { wallet } = useWallet();

const signers = await wallet.delegatedSigners();

See the React SDK reference for more details.

import { CrossmintWallets, createCrossmint } from "@crossmint/wallets-sdk";

const crossmint = createCrossmint({
    apiKey: "<your-server-api-key>",
});

const crossmintWallets = CrossmintWallets.from(crossmint);

const wallet = await crossmintWallets.getWallet(
    "email:user@example.com:evm",
    { chain: "base-sepolia", signer: { type: "email" } }
);

const signers = await wallet.delegatedSigners();

Returns

signers

DelegatedSigner[]

The delegated signers.

Show properties

signer

string

The locator of the signer.

React Native

import { useWallet } from '@crossmint/client-sdk-react-native-ui';

const { wallet } = useWallet();

const signers = await wallet.delegatedSigners();

See the React Native SDK reference for more details.

curl --request GET \
    --url https://staging.crossmint.com/api/2025-06-09/wallets/email:user@example.com:evm \
    --header 'X-API-KEY: <x-api-key>'

See the API reference for more details.

Introduction

Quickstarts ⚡️

Concepts

Guides

API Reference

Delegated Signers

Prerequisites

Adding a delegated signer

Parameters

Getting all delegated signers

Returns

Introduction

Quickstarts ⚡️

Concepts

Guides

API Reference

​Prerequisites

​Adding a delegated signer

​Parameters

​Getting all delegated signers

​Returns

Prerequisites

Adding a delegated signer

Parameters

Getting all delegated signers

Returns