EVM

EVM chains like Ethereum, Polygon, Base etc support the following signature kinds:

• Transaction: unsigned transaction.

• Message: an arbitrary message.

• Eip712: typed structured data defined in EIP-712.

Transaction

Signs an unsigned transaction.

Field	Description	Type - Optional
blockchainKind	Evm	String
kind	Transaction	String
transaction	The unsigned hex encoded transaction as shown below.	String

{
  "blockchainKind": "Evm",
  "kind": "Transaction",
  "message": "0x02e783aa36a71503850d40e49def82520894e5a2ebc128e262ab1e3bd02bffbe16911adfbffb0180c0"
}

Typescript Example with EthersJs

First install the Ethers JS. You can find the full documentation here: https://docs.ethers.org/v6/

Here a code sample to generate a signature via the Dfns TypeScript SDK:

import { parseUnits, Transaction } from 'ethers'

const walletId = 'wa-6lbfv-9esgj-88s80c0qsih0a393'

const transaction = Transaction.from({
  to: '0xa238b6008Bc2FBd9E386A5d4784511980cE504Cd',
  value: '1',
  gasLimit: '21000',
  maxPriorityFeePerGas: parseUnits('5', 'gwei'),
  maxFeePerGas: parseUnits('20', 'gwei'),
  nonce: 3,
  type: 2,
  chainId: 11155111,
})

const res = await dfnsClient.wallets.generateSignature({
  walletId,
  body: { kind: 'Transaction', transaction: transaction.unsignedSerialized },
})

Message

Signs an arbitrary hex encoded message.

Field	Description	Type - Optional
blockchainKind	Evm	String
kind	Message	String
message	An arbitrary hex encoded message.	String

{
  "blockchainKind": "Evm",
  "kind": "Message",
  "message": "0x49206c6f76652044666e73"
}

EIP-712 TypedData

Signs a typed structured data defined in EIP-712.

Field	Description	Type - Optional
blockchainKind	Evm	String
kind	Eip712	String
types	Type definitions.	Map<String, TypedDataField[]>
domain	Domain separator.	Eip712Domain
message	Structured message to sign.	Object

TypedDataField

Field	Description	Type - Optional
name	Field name.	String
type	Field type.	String

Eip712Domain

Field	Description	Type - Optional
name	Name of the signing domain.	String
version	Current major version of the signing domain.	String
chainId	Chain ID.	Integer
verifyingContract	The address of the contract that will verify the signature.	String
salt	32-byte value as a last-resort domain separator.	String

{
  "blockchainKind": "Evm",
  "kind": "Eip712",
  "types": {
    "Person": [
      { "name": "name", "type": "string" },
      { "name": "wallet", "type": "address" }
    ],
    "Mail": [
      { "name": "from", "type": "Person" },
      { "name": "to", "type": "Person" },
      { "name": "contents", "type": "string" }
    ]
  },
  "domain": {
    "name": "Ether Mail",
    "version": "1",
    "chainId": 1,
    "verifyingContract": "0x1b352de7a926ebd1bf52194dab487c2cb0793a9b",
    "salt": "0xf2d857f4a3edcb9b78b4d503bfe733db1e3f6cdc2b7971ee739626c97e86a558"
  },
  "message": {
    "from": {
      "name": "Chris",
      "wallet": "0x00e3495cf6af59008f22ffaf32d4c92ac33dac47"
    },
    "to": {
      "name": "Bob",
      "wallet": "0xcc0ee1a1c5e788b61916c8f1c96c960f9a9d3db7"
    },
    "contents": "Hello, Bob!"
  }
}