Build Transaction

curl -X POST https://api.dzap.io/v1/buildTx \
  -H "Content-Type: application/json" \
  -d '{
    "sender": "0x99BCEBf44433E901597D9fCb16E799a4847519f6",
    "refundee": "0x99BCEBf44433E901597D9fCb16E799a4847519f6",
    "fromChain": 42161,
    "gasless": false,
    "data": [
      {
        "amount": "1000000",
        "srcToken": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
        "destToken": "0x4200000000000000000000000000000000000006",
        "toChain": 8453,
        "protocol": "across",
        "recipient": "0x99BCEBf44433E901597D9fCb16E799a4847519f6",
        "slippage": 1
      }
    ]
  }'

const request = {
  sender: userAccount,
  refundee: userAccount,
  fromChain: 42161,
  gasless: false,
  data: [
    {
      amount: '1000000',
      srcToken: '0xaf88d065e77c8cC2239327C5EDb3A432268e5831',
      destToken: '0x4200000000000000000000000000000000000006',
      toChain: 8453,
      protocol: 'across',
      recipient: userAccount,
      slippage: 1,
    },
  ],
};

// Build only:
const buildResponse = await dzap.buildTradeTxn(request);

// Or build + sign + execute in one call:
const result = await dzap.trade({ request, signer });

{
  "status": "success",
  "txId": "0xabc123...",
  "chainId": 42161,
  "transaction": {
    "from": "0x99BCEBf44433E901597D9fCb16E799a4847519f6",
    "data": "0x...",
    "to": "0x1d46863e3592745008b5CbbAC12014F67329A9b8",
    "value": "0",
    "gasLimit": "350000"
  },
  "gasless": false,
  "private": false,
  "quotes": {
    "across": {
      "provider": "across",
      "destAmount": "300000000000000",
      "minDestAmount": "298500000000000",
      "duration": "90"
    }
  },
  "additionalInfo": {},
  "updatedQuotes": {}
}

POST

buildTx

curl -X POST https://api.dzap.io/v1/buildTx \
  -H "Content-Type: application/json" \
  -d '{
    "sender": "0x99BCEBf44433E901597D9fCb16E799a4847519f6",
    "refundee": "0x99BCEBf44433E901597D9fCb16E799a4847519f6",
    "fromChain": 42161,
    "gasless": false,
    "data": [
      {
        "amount": "1000000",
        "srcToken": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
        "destToken": "0x4200000000000000000000000000000000000006",
        "toChain": 8453,
        "protocol": "across",
        "recipient": "0x99BCEBf44433E901597D9fCb16E799a4847519f6",
        "slippage": 1
      }
    ]
  }'

const request = {
  sender: userAccount,
  refundee: userAccount,
  fromChain: 42161,
  gasless: false,
  data: [
    {
      amount: '1000000',
      srcToken: '0xaf88d065e77c8cC2239327C5EDb3A432268e5831',
      destToken: '0x4200000000000000000000000000000000000006',
      toChain: 8453,
      protocol: 'across',
      recipient: userAccount,
      slippage: 1,
    },
  ],
};

// Build only:
const buildResponse = await dzap.buildTradeTxn(request);

// Or build + sign + execute in one call:
const result = await dzap.trade({ request, signer });

{
  "status": "success",
  "txId": "0xabc123...",
  "chainId": 42161,
  "transaction": {
    "from": "0x99BCEBf44433E901597D9fCb16E799a4847519f6",
    "data": "0x...",
    "to": "0x1d46863e3592745008b5CbbAC12014F67329A9b8",
    "value": "0",
    "gasLimit": "350000"
  },
  "gasless": false,
  "private": false,
  "quotes": {
    "across": {
      "provider": "across",
      "destAmount": "300000000000000",
      "minDestAmount": "298500000000000",
      "duration": "90"
    }
  },
  "additionalInfo": {},
  "updatedQuotes": {}
}

Takes the route(s) you selected from /v1/quotes (via protocol) and returns transaction data ready to sign and submit.

Body

string

required

Wallet address sending the transaction.

string

required

Address to receive refunds.

integer

required

Source chain ID for every item in data.

boolean

required

false for standard execution; true for the gasless/intent flow.

object[]

required

Array of trade legs to build.

Show data item

string

required

Amount in the source token’s smallest unit.

string

required

Source token contract address.

integer

Source token decimals.

string

required

Destination token contract address.

integer

Destination token decimals.

integer

required

Destination chain ID.

string

required

Provider ID selected from the quote response (e.g. recommendedSource).

string

required

Address to receive the destination tokens.

number

required

Slippage tolerance, in percent.

object

Route-specific data echoed back from the quote.

string

Pre-signed permit data for the source token.

boolean

Request private/MEV-protected execution.

boolean

Skip gas estimation for a faster build.

boolean

Set true if Permit2 approval already exists for every token in data.

string

Required for Bitcoin-chain transactions only.

Response - non-gasless (`gasless: false`)

string

"success" when the build succeeds.

string

Unique build/transaction ID - use for status polling and broadcasting.

integer

Chain where the transaction is to be executed.

object

Chain-specific payload - shape depends on the chain type.

Show transaction (evm)

string

Hex-encoded calldata.

string

Contract to call.

string

Native value to send, in wei.

string

Show transaction (svm - Solana)

string

integer

Show transaction (btc - Bitcoin)

string

object[]

PSBT inputs.

object[]

PSBT outputs.

integer

Show transaction (btcln - Bitcoin Lightning)

string

"bolt11"

string

integer

Show transaction (HyperLiquid)

object[]

Array of { domain, types, primaryType, message } typed-data payloads to sign.

boolean

false.

boolean

Echoes whether private/MEV-protected execution was used.

object

Per-pair summary keyed by pair ID.

Show quotes[pairId]

string

object

Provider-specific extra data (shape varies).

string

@deprecated - top-level mirror of transaction.data for EVM chains.

string

@deprecated - top-level mirror of transaction.from.

string

@deprecated - top-level mirror of transaction.to.

string

@deprecated - top-level mirror of transaction.value.

string

@deprecated - top-level mirror of transaction.gasLimit.

object

{ blockhash, lastValidBlockHeight }, present for Solana transactions.

object

{ inputs, outputs, feeRate }, present for Bitcoin transactions.

object

{ paymentRequestType: "bolt11", paymentRequest, paymentExpiry }, present for Bitcoin Lightning.

object

Record<string, Record<string, unknown>>.

object

Record<string, string> - refreshed destination amounts keyed by pair ID.

Response - gasless (`gasless: true`)

string

"success".

string

Intent ID - pass to /v1/gasless/executeTx once signed.

object

Typed-data payload to sign.

Show transaction (bridge)

string

Absent for pure EIP-2612/bridge-only intents.

string

"bridge"

string

Show transaction (swap)

string

"swap"

string

object

Same shape as the non-gasless response above.

boolean

true.

boolean

false.

Examples

curl -X POST https://api.dzap.io/v1/buildTx \
  -H "Content-Type: application/json" \
  -d '{
    "sender": "0x99BCEBf44433E901597D9fCb16E799a4847519f6",
    "refundee": "0x99BCEBf44433E901597D9fCb16E799a4847519f6",
    "fromChain": 42161,
    "gasless": false,
    "data": [
      {
        "amount": "1000000",
        "srcToken": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
        "destToken": "0x4200000000000000000000000000000000000006",
        "toChain": 8453,
        "protocol": "across",
        "recipient": "0x99BCEBf44433E901597D9fCb16E799a4847519f6",
        "slippage": 1
      }
    ]
  }'

const request = {
  sender: userAccount,
  refundee: userAccount,
  fromChain: 42161,
  gasless: false,
  data: [
    {
      amount: '1000000',
      srcToken: '0xaf88d065e77c8cC2239327C5EDb3A432268e5831',
      destToken: '0x4200000000000000000000000000000000000006',
      toChain: 8453,
      protocol: 'across',
      recipient: userAccount,
      slippage: 1,
    },
  ],
};

// Build only:
const buildResponse = await dzap.buildTradeTxn(request);

// Or build + sign + execute in one call:
const result = await dzap.trade({ request, signer });

{
  "status": "success",
  "txId": "0xabc123...",
  "chainId": 42161,
  "transaction": {
    "from": "0x99BCEBf44433E901597D9fCb16E799a4847519f6",
    "data": "0x...",
    "to": "0x1d46863e3592745008b5CbbAC12014F67329A9b8",
    "value": "0",
    "gasLimit": "350000"
  },
  "gasless": false,
  "private": false,
  "quotes": {
    "across": {
      "provider": "across",
      "destAmount": "300000000000000",
      "minDestAmount": "298500000000000",
      "duration": "90"
    }
  },
  "additionalInfo": {},
  "updatedQuotes": {}
}

Use the txId to poll /v1/status once the transaction has been signed and sent.

Last modified on July 14, 2026

Quote Execute

Getting started

Fuse API

Trade API

Build Transaction

Body

Response - non-gasless (`gasless: false`)

Response - gasless (`gasless: true`)

Examples

​Body

​Response - non-gasless (gasless: false)

​Response - gasless (gasless: true)

​Examples

Body

Response - non-gasless (`gasless: false`)

Response - gasless (`gasless: true`)

Examples