Class TransactionBuilder

A high-level builder for constructing Cardano transactions.

This class provides a fluent interface to incrementally add inputs, outputs, certificates, metadata, and other components to a transaction. It encapsulates the complexities of transaction assembly, fee calculation, and balancing.

Properties

ptr

ptr: number

Methods

addCertificate

addCertificate(
params: { certificate: Certificate; redeemer?: PlutusData },
): TransactionBuilder
Adds a certificate to the transaction.

Certificates are used to perform various on-chain actions like staking, delegation, or registering entities like stake pools and DReps.
Parameters
- params: { certificate: Certificate; redeemer?: PlutusData }
  The parameters for the function.
  - certificate: Certificate
    The certificate object to add to the transaction.
  - Optionalredeemer?: PlutusData
    Optional. The redeemer data required if the certificate action is controlled by a Plutus script.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:1353

addDatum

addDatum(datum: PlutusData): TransactionBuilder
Adds a Plutus datum to the transaction's witness set.

This allows the datum to be referenced by its hash from a transaction output, satisfying a script's requirement without including the full datum directly in the output itself.
Parameters
- datum: PlutusData
  The PlutusData object to add to the transaction witnesses.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:854

addInput

addInput(
params: { datum?: PlutusData; redeemer?: PlutusData; utxo: UTxO },
): TransactionBuilder
Adds an input to the transaction to be spent.

Optionally, a redeemer and datum can be provided. These are typically required when spending a UTxO that is locked at a Plutus script address.
Parameters
- params: { datum?: PlutusData; redeemer?: PlutusData; utxo: UTxO }
  The parameters for the function.
  - Optionaldatum?: PlutusData
    Optional. The datum that was locking the script output.
  - Optionalredeemer?: PlutusData
    Optional. The redeemer to use for unlocking the script.
  - utxo: UTxO
    The Unspent Transaction Output (UTxO) to be spent.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:680

addOutput

addOutput(output: TxOut): TransactionBuilder
Adds a transaction output to send a specific value to an address.
Parameters
- output: TxOut
  The transaction output to add.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:725

addReferenceInput

addReferenceInput(utxo: UTxO): TransactionBuilder
Adds a reference input to the transaction.

Reference inputs allow Plutus scripts to inspect the data, datum, and script of a UTxO without actually spending it. This is useful for looking up on-chain information.
Parameters
- utxo: UTxO
  The UTxO to be used as a reference input.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:484

addScript

addScript(script: Script): TransactionBuilder
Adds a script to the transaction's witness set.

This is necessary when using a script that is not already available on-chain via a reference input, such as a minting policy or a native script for a required signer.
Parameters
- script: Script
  The script object (Plutus or Native) to add.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:1393

addSigner

addSigner(pkh: string): TransactionBuilder
Adds a required signer to the transaction.
Parameters
- pkh: string
  The public key hash (PKH) of the required signer as a hex string.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:834

build

build(): Promise<string>
Finalizes the transaction by performing coin selection, balancing, and fee calculation. This is the final step in the building process.

Returns Promise<string>
string - The built transaction as a CBOR hex string.

Throws
If the transaction build fails due to insufficient funds, invalid inputs, or other errors.
- Defined in txBuilder/TransactionBuilder.ts:1854

delegateStake

delegateStake(
    params: {
        poolId: string;
        redeemer?: PlutusData;
        rewardAddress: string | RewardAddress;
    },
): TransactionBuilder
Adds a stake delegation certificate to the transaction.

This delegates the staking power of a reward address to a specified stake pool. An optional redeemer can be provided for script-controlled stake credentials.
Parameters
- params: { poolId: string; redeemer?: PlutusData; rewardAddress: string | RewardAddress }
  The parameters for the function.
  - poolId: string
    The bech32-encoded ID of the stake pool to delegate to.
  - Optionalredeemer?: PlutusData
    Optional. The redeemer for a script-controlled stake credential.
  - rewardAddress: string | RewardAddress
    The bech32-encoded stake address to delegate from.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:1030

delegateVotingPower

delegateVotingPower(
    params: {
        drepId: string;
        redeemer?: PlutusData;
        rewardAddress: string | RewardAddress;
    },
): TransactionBuilder
Adds a voting delegation certificate to the transaction.

This delegates the voting power of a stake address to a specified DRep (Decentralized Representative) for on-chain governance.
Parameters
- params: { drepId: string; redeemer?: PlutusData; rewardAddress: string | RewardAddress }
  The parameters for the function.
  - drepId: string
    The bech32-encoded ID of the DRep to delegate to. The DRep ID can be in CIP-129 format or CIP-105 format.
  - Optionalredeemer?: PlutusData
    Optional. The redeemer for a script-controlled stake credential.
  - rewardAddress: string | RewardAddress
    The bech32-encoded stake address to delegate from.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:1081

deregisterDRep

deregisterDRep(
params: { drepId: string; redeemer?: PlutusData },
): TransactionBuilder
Adds a DRep deregistration certificate to the transaction.

This action retires the DRep, making them ineligible for future governance proposals. An optional redeemer can be provided for script-controlled DRep credentials.
Parameters
- params: { drepId: string; redeemer?: PlutusData }
  The parameters for the function.
  - drepId: string
    The bech32-encoded ID of the DRep to deregister. This can be in either CIP-105 or CIP-129 format.
  - Optionalredeemer?: PlutusData
    Optional. The redeemer for a script-controlled DRep credential.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:1261

deregisterStakeAddress

deregisterStakeAddress(
params: { redeemer?: PlutusData; rewardAddress: string | RewardAddress },
): TransactionBuilder
Adds a stake deregistration certificate to the transaction.

This action retires the stake address and initiates the refund of the key deposit. An optional redeemer can be provided for script-controlled stake credentials.
Parameters
- params: { redeemer?: PlutusData; rewardAddress: string | RewardAddress }
  The parameters for the function.
  - Optionalredeemer?: PlutusData
    Optional. The redeemer for a script-controlled stake credential.
  - rewardAddress: string | RewardAddress
    The stake address to deregister, as a bech32 string or a RewardAddress object.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:984

expiresAfter

expiresAfter(date: Date): TransactionBuilder
Sets the transaction's expiration to a specific, absolute date and time.

This function marks the transaction as invalid if it is not included in a block before the specified date.
Parameters
- date: Date
  The absolute date and time after which the transaction will be invalid.
Returns TransactionBuilder
The builder instance for chaining.
Example
```
// Set the transaction to expire on New Year's Day, 2026.
const expiryDate = new Date('2026-01-01T00:00:00Z');
txBuilder.expiresAfter(expiryDate);
```
- Defined in txBuilder/TransactionBuilder.ts:409

expiresIn

expiresIn(seconds: number): TransactionBuilder
Sets the transaction to be valid for a specific duration from now.

This is a convenience method that calculates a future expiration date and sets it. The transaction will be marked as invalid if it is not included in a block within the specified duration.
Parameters
- seconds: number
  The number of seconds from now that the transaction should remain valid.
Returns TransactionBuilder
The builder instance for chaining.
Example
```
// Set the transaction to expire in 3 minutes (180 seconds) from now.
txBuilder.setValidFor(180);
```
- Defined in txBuilder/TransactionBuilder.ts:385

getRefCount

getRefCount(): number
Retrieves the current reference count of the native object. This is primarily for debugging and diagnostic purposes.

Returns number
The reference count.
- Defined in txBuilder/TransactionBuilder.ts:1891

lockLovelace

lockLovelace(
    params: {
        amount: number | bigint;
        datum?: Datum;
        scriptAddress: string | Address;
    },
): TransactionBuilder
Adds a transaction output to lock a specific amount of lovelace at a script address.

This is used to send funds to a smart contract, where the funds are locked until the script conditions are met. A datum must be provided to be attached to the script output.
Parameters
- params: { amount: number | bigint; datum?: Datum; scriptAddress: string | Address }
  The parameters for the function.
  - amount: number | bigint
    The amount of lovelace to lock.
  - Optionaldatum?: Datum
    The datum to attach to the output, which will be available to the script.
  - scriptAddress: string | Address
    The recipient script address as a bech32 string or an Address object.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:574

lockValue

lockValue(
params: { datum: Datum; scriptAddress: string | Address; value: Value },
): TransactionBuilder
Adds a transaction output to lock a value (lovelace and/or other assets) at a script address.

This is used to send funds to a smart contract, where they are locked until the script conditions are met. A datum must be provided with the output.
Parameters
- params: { datum: Datum; scriptAddress: string | Address; value: Value }
  The parameters for the function.
  - datum: Datum
    The datum to attach to the output, which will be available to the script.
  - scriptAddress: string | Address
    The recipient script address as a bech32 string or an Address object.
  - value: Value
    The value object, containing the coins and/or other assets to lock.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:629

mintToken

mintToken(
    params: {
        amount: number | bigint;
        assetIdHex: string;
        redeemer?: PlutusData;
    },
): TransactionBuilder
Adds a token minting or burning operation to the transaction using a concatenated Asset ID.
Parameters
- params: { amount: number | bigint; assetIdHex: string; redeemer?: PlutusData }
  The parameters for the function.
  - amount: number | bigint
    The quantity to mint (positive integer) or burn (negative integer).
  - assetIdHex: string
    The hex-encoded Asset ID (concatenation of the policy ID and asset name).
  - Optionalredeemer?: PlutusData
    Optional. The redeemer required if the minting policy is a Plutus script.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:770

padSignerCount

padSignerCount(count: number): TransactionBuilder
Pads the transaction with space for a specified number of additional signers.

This is used for fee calculation purposes to ensure the final transaction fee is sufficient to cover signatures that will be added after the transaction is built (e.g., by co-signers). This method does not add any actual required signers to the transaction witnesses.
Parameters
- count: number
  The number of additional signer "slots" to account for in the fee calculation.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:823

proposeCommitteeUpdate

proposeCommitteeUpdate(
    params: {
        anchor: Anchor;
        governanceActionId?: GovernanceActionId;
        membersToBeAdded: CommitteeMembers;
        membersToBeRemoved: CredentialSet;
        newQuorum: UnitInterval;
        rewardAddress: string | RewardAddress;
    },
): TransactionBuilder
Adds a proposal to update the constitutional committee to the transaction.

This governance action can add new members, remove existing members, and change the required quorum for committee votes.
Parameters
- params: {
      anchor: Anchor;
      governanceActionId?: GovernanceActionId;
      membersToBeAdded: CommitteeMembers;
      membersToBeRemoved: CredentialSet;
      newQuorum: UnitInterval;
      rewardAddress: string | RewardAddress;
  }
  The parameters for the function.
  - anchor: Anchor
    The anchor containing the URL and hash of off-chain metadata for the proposal.
  - OptionalgovernanceActionId?: GovernanceActionId
    Optional. The ID of the most recent hard fork initiation action. Can be undefined if this is the first proposal of this type on the network.
  - membersToBeAdded: CommitteeMembers
    An array of CommitteeMember objects (credential and epoch) for new members.
  - membersToBeRemoved: CredentialSet
    An array of Credential objects for committee members to be removed.
  - newQuorum: UnitInterval
    The new quorum for the committee, as a unit interval (e.g., { numerator: 1n, denominator: 2n }).
  - rewardAddress: string | RewardAddress
    The reward address where the governance action deposit will be refunded.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:1673

proposeHardfork

proposeHardfork(
    params: {
        anchor: Anchor;
        governanceActionId?: GovernanceActionId;
        rewardAddress: string | RewardAddress;
        version: ProtocolVersion;
    },
): TransactionBuilder
Adds a hard fork initiation proposal to the transaction.

This governance action is used to propose an upgrade to a new major protocol version.
Parameters
- params: {
      anchor: Anchor;
      governanceActionId?: GovernanceActionId;
      rewardAddress: string | RewardAddress;
      version: ProtocolVersion;
  }
  The parameters for the function.
  - anchor: Anchor
    The anchor containing the URL and hash of off-chain metadata for the proposal.
  - OptionalgovernanceActionId?: GovernanceActionId
    Optional. The ID of the most recent hard fork initiation action. Can be undefined if this is the first proposal of this type on the network.
  - rewardAddress: string | RewardAddress
    The reward address where the governance action deposit will be refunded.
  - version: ProtocolVersion
    The protocol version to upgrade to.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:1494

proposeInfoAction

proposeInfoAction(
params: { anchor: Anchor; rewardAddress: string | RewardAddress },
): TransactionBuilder
Adds an informational governance action proposal to the transaction.

This type of action has no direct on-chain effect but serves to record information or a statement on the blockchain, retrievable via its metadata anchor.
Parameters
- params: { anchor: Anchor; rewardAddress: string | RewardAddress }
  The parameters for the function.
  - anchor: Anchor
    The anchor containing the URL and hash of the off-chain information.
  - rewardAddress: string | RewardAddress
    The reward address where the governance action deposit will be refunded.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:1818

proposeNewConstitution

proposeNewConstitution(
    params: {
        anchor: Anchor;
        constitution: Constitution;
        governanceActionId?: GovernanceActionId;
        rewardAddress: string | RewardAddress;
    },
): TransactionBuilder
Adds a new constitution proposal to the transaction.

This governance action proposes to replace the current on-chain constitution with a new one.
Parameters
- params: {
      anchor: Anchor;
      constitution: Constitution;
      governanceActionId?: GovernanceActionId;
      rewardAddress: string | RewardAddress;
  }
  The parameters for the function.
  - anchor: Anchor
    The anchor containing the URL and hash of off-chain metadata for this specific proposal.
  - constitution: Constitution
    The new constitution being proposed, which includes its own anchor and an optional script hash.
  - OptionalgovernanceActionId?: GovernanceActionId
    Optional. The ID of the most recent hard fork initiation action. Can be undefined if this is the first proposal of this type on the network.
  - rewardAddress: string | RewardAddress
    The reward address where the governance action deposit will be refunded.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:1755

proposeNoConfidence

proposeNoConfidence(
    params: {
        anchor: Anchor;
        governanceActionId?: GovernanceActionId;
        rewardAddress: string | RewardAddress;
    },
): TransactionBuilder
Adds a "no confidence" proposal to the transaction.

This governance action is used to express a lack of confidence in the current constitutional committee.
Parameters
- params: {
      anchor: Anchor;
      governanceActionId?: GovernanceActionId;
      rewardAddress: string | RewardAddress;
  }
  The parameters for the function.
  - anchor: Anchor
    The anchor containing the URL and hash of off-chain metadata for the proposal.
  - OptionalgovernanceActionId?: GovernanceActionId
    Optional. The ID of the most recent hard fork initiation action. Can be undefined if this is the first proposal of this type on the network.
  - rewardAddress: string | RewardAddress
    The reward address where the governance action deposit will be refunded.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:1618

proposeParameterChange

proposeParameterChange(
    params: {
        anchor: Anchor;
        governanceActionId?: GovernanceActionId;
        policyHash: string;
        protocolParamUpdate: Partial<ProtocolParameters>;
        rewardAddress: string | RewardAddress;
    },
): TransactionBuilder
Adds a protocol parameter change proposal to the transaction.

This governance action is used to propose modifications to the network's protocol parameters.
Parameters
- params: {
      anchor: Anchor;
      governanceActionId?: GovernanceActionId;
      policyHash: string;
      protocolParamUpdate: Partial<ProtocolParameters>;
      rewardAddress: string | RewardAddress;
  }
  The parameters for the function.
  - anchor: Anchor
    The anchor containing the URL and hash of off-chain metadata for the proposal.
  - OptionalgovernanceActionId?: GovernanceActionId
    Optional. The ID of the most recent parameter change action. Can be undefined if this is the first proposal of this type on the network.
  - policyHash: string
    The hex-encoded hash of the governance action policy script (guardrails script).
  - protocolParamUpdate: Partial<ProtocolParameters>
    An object containing the specific protocol parameters to be updated.
  - rewardAddress: string | RewardAddress
    The reward address where the governance action deposit will be refunded.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:1424

proposeTreasuryWithdrawals

proposeTreasuryWithdrawals(
    params: {
        anchor: Anchor;
        policyHash?: string;
        rewardAddress: string | RewardAddress;
        withdrawals: Withdrawals;
    },
): TransactionBuilder
Adds a treasury withdrawals proposal to the transaction.

This governance action proposes the withdrawal of funds from the treasury to be distributed to a set of specified reward accounts.
Parameters
- params: {
      anchor: Anchor;
      policyHash?: string;
      rewardAddress: string | RewardAddress;
      withdrawals: Withdrawals;
  }
  The parameters for the function.
  - anchor: Anchor
    The anchor containing the URL and hash of off-chain metadata for the proposal.
  - OptionalpolicyHash?: string
    Optional. The hex-encoded hash of the governance action policy script (guardrails script).
  - rewardAddress: string | RewardAddress
    The reward address where the governance action deposit will be refunded.
  - withdrawals: Withdrawals
    A map where keys are the Bech32-encoded reward addresses of the recipients and values are the corresponding lovelace amounts to be withdrawn.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:1553

registerDRep

registerDRep(
params: { anchor: Anchor; drepId: string; redeemer?: PlutusData },
): TransactionBuilder
Adds a DRep registration certificate to the transaction.
Parameters
- params: { anchor: Anchor; drepId: string; redeemer?: PlutusData }
  The parameters for the function.
  - anchor: Anchor
    An object containing the URL and hash of the DRep's metadata.
  - drepId: string
    The bech32-encoded ID of the DRep to delegate to. The DRep ID can be in CIP-129 format or CIP-105 format.
  - Optionalredeemer?: PlutusData
    Optional. The redeemer for a script-controlled DRep credential.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:1136

registerStakeAddress

registerStakeAddress(
params: { redeemer?: PlutusData; rewardAddress: string | RewardAddress },
): TransactionBuilder
Adds a stake registration certificate to the transaction.

This allows the specified stake address to start participating in staking and receiving rewards. An optional redeemer can be provided for script-controlled stake credentials.
Parameters
- params: { redeemer?: PlutusData; rewardAddress: string | RewardAddress }
  The parameters for the function.
  - Optionalredeemer?: PlutusData
    Optional. The redeemer for a script-controlled stake credential.
  - rewardAddress: string | RewardAddress
    The stake address to register, as a bech32 string or a RewardAddress object.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:939

sendLovelace

sendLovelace(
params: { address: string | Address; amount: number | bigint },
): TransactionBuilder
Adds a transaction output to send a specific amount of lovelace to an address.
Parameters
- params: { address: string | Address; amount: number | bigint }
  The parameters for the function.
  - address: string | Address
    The recipient's address as a bech32 string or an Address object.
  - amount: number | bigint
    The amount of lovelace to send.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:543

sendValue

sendValue(
params: { address: string | Address; value: Value },
): TransactionBuilder
Adds a transaction output to send a value (lovelace and/or other assets) to an address.
Parameters
- params: { address: string | Address; value: Value }
  The parameters for the function.
  - address: string | Address
    The recipient's address as a bech32 string or an Address object.
  - value: Value
    The value object, containing the coins and/or other assets to send.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:509

setChangeAddress

setChangeAddress(address: string | Address): TransactionBuilder
Sets the change address for the transaction. This is where any remaining funds from inputs will be sent after covering outputs and fees.
Parameters
- address: string | Address
  The change address as a bech32 string or an Address object.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:243

setCoinSelector

setCoinSelector(coinSelector: CoinSelector): TransactionBuilder
Sets a custom coin selection strategy for the transaction.

The coin selector determines how UTxOs are chosen to cover the transaction's required value. If this method is not called, the builder will use a default coin selection strategy ('largest-first').
Parameters
- coinSelector: CoinSelector
  The coin selection strategy to use.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:177

setCollateralChangeAddress

setCollateralChangeAddress(address: string | Address): TransactionBuilder
Sets the collateral change address for the transaction.

This address specifies where any remaining balance from collateral inputs will be sent. Collateral is required for transactions involving Plutus scripts.
Parameters
- address: string | Address
  The collateral return address as a bech32 string or an Address object.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:258

setCollateralUtxos

setCollateralUtxos(utxos: UTxO[]): TransactionBuilder
Sets a specific list of UTXOs to be used for collateral.

Collateral is required for transactions involving Plutus scripts. If this method is not called, the builder will attempt to select collateral from the general UTXO set provided via the setUtxos method.
Parameters
- utxos: UTxO[]
  An array of UTxOs to be designated for collateral.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:336

setDonation

setDonation(donation: number | bigint): TransactionBuilder
Sets the donation amount for the transaction being built.

Donations are a Conway-era feature that contribute a specific amount to the treasury.
Parameters
- donation: number | bigint
  The donation amount in lovelace.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:302

setInvalidAfter

setInvalidAfter(slot: number | bigint): TransactionBuilder
Sets the transaction's expiration, also known as Time To Live (TTL).

This function marks the transaction as invalid if it is not included in a block before the specified time.
Parameters
- slot: number | bigint
  The absolute slot number after which this transaction will be invalid.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:362

setInvalidBefore

setInvalidBefore(slot: number | bigint): TransactionBuilder
Sets the transaction's validity start time using an absolute slot number.

This function marks the transaction as invalid if it is included in a block created before the specified slot.
Parameters
- slot: number | bigint
  The absolute slot number before which this transaction is invalid.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:429

setMetadata

setMetadata(
params: { metadata: string | object; tag: number | bigint },
): TransactionBuilder
Attaches metadata to the transaction under a specific label (tag).
Parameters
- params: { metadata: string | object; tag: number | bigint }
  The parameters for the function.
  - metadata: string | object
    The metadata content. Can be a plain object, or a pre-serialized JSON string.
  - tag: number | bigint
    A unique integer label for this piece of metadata.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:744

setMinimumFee

setMinimumFee(fee: number | bigint): TransactionBuilder
Sets a minimum transaction fee.

This function allows you to specify a minimum fee for the transaction in lovelace. The final fee calculated by the builder during the build process will be at least this amount.
Parameters
- fee: number | bigint
  The minimum fee amount in lovelace.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:285

setNetworkId

setNetworkId(networkId: NetworkId): TransactionBuilder
Sets the network ID for the transaction.

This specifies the target network (e.g., Mainnet or a Testnet) for which the transaction is intended.
Parameters
- networkId: NetworkId
  The network ID to assign to the transaction.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:231

setTxEvaluator

setTxEvaluator(txEvaluator: TxEvaluator): TransactionBuilder
Sets a custom transaction evaluator.

The evaluator is responsible for calculating the execution units (memory and steps) required for any Plutus scripts in the transaction. If this method is not called, the builder will use a default evaluator that relies on the configured provider.
Parameters
- txEvaluator: TxEvaluator
  The transaction evaluator to use.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:205

setUtxos

setUtxos(utxos: UTxO[]): TransactionBuilder
Sets the available UTXOs for the builder to use for coin selection.
Parameters
- utxos: UTxO[]
  An array of available UTxOs.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:315

updateDRep

updateDRep(
params: { anchor: Anchor; drepId: string; redeemer?: PlutusData },
): TransactionBuilder
Adds an update DRep certificate in the transaction.
Parameters
- params: { anchor: Anchor; drepId: string; redeemer?: PlutusData }
  The parameters for the function.
  - anchor: Anchor
    An object containing the URL and hash of the DRep's metadata.
  - drepId: string
    The bech32-encoded ID of the DRep to deregister. This can be in either CIP-105 or CIP-129 format.
  - Optionalredeemer?: PlutusData
    Optional redeemer data for script-based DReps.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:1198

validAfter

validAfter(seconds: number): TransactionBuilder
Sets the transaction to become valid only after a specified duration from now. This is a convenience method that calculates a future start date.
Parameters
- seconds: number
  The number of seconds from now to wait before the transaction becomes valid.
Returns TransactionBuilder
The builder instance for chaining.
Example
```
// Make the transaction valid only after 1 hour (3600 seconds) has passed.
txBuilder.validAfter(3600);
```
- Defined in txBuilder/TransactionBuilder.ts:468

validFromDate

validFromDate(date: Date): TransactionBuilder
Sets the transaction's validity start time to a specific, absolute date and time. The transaction will be invalid if processed before this date.
Parameters
- date: Date
  The absolute date and time from which the transaction will be valid.
Returns TransactionBuilder
The builder instance for chaining.
Example
```
// Make the transaction valid starting on New Year's Day, 2026.
const startDate = new Date('2026-01-01T00:00:00Z');
txBuilder.validFromDate(startDate);
```
- Defined in txBuilder/TransactionBuilder.ts:449

vote

vote(
    params: {
        actionId: string | GovernanceActionId;
        redeemer?: PlutusData;
        voter: Voter;
        votingProcedure: VotingProcedure;
    },
): TransactionBuilder
Adds a vote for a specific governance action to the transaction.

This function allows a voter to submit their vote for a given governance action.
Parameters
- params: {
      actionId: string | GovernanceActionId;
      redeemer?: PlutusData;
      voter: Voter;
      votingProcedure: VotingProcedure;
  }
  The parameters for the function.
  - actionId: string | GovernanceActionId
    The ID of the governance action being voted on.
  - Optionalredeemer?: PlutusData
    Optional. Redeemer data required if the voter is script-controlled.
  - voter: Voter
    The voter participating in the governance action.
  - votingProcedure: VotingProcedure
    The voting procedure, including the vote choice.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:1297

withdrawRewards

withdrawRewards(
    params: {
        amount: number | bigint;
        redeemer?: PlutusData;
        rewardAddress: string | RewardAddress;
    },
): TransactionBuilder
Adds a withdrawal from a reward account to the transaction.

The amount specified must be the full available reward balance for the account. An optional redeemer can be provided for script-locked withdrawals.
Parameters
- params: {
      amount: number | bigint;
      redeemer?: PlutusData;
      rewardAddress: string | RewardAddress;
  }
  The parameters for the function.
  - amount: number | bigint
    The full amount of rewards to withdraw in lovelace.
  - Optionalredeemer?: PlutusData
    Optional. The redeemer for a script-locked withdrawal.
  - rewardAddress: string | RewardAddress
    The reward account address as a bech32 string or a RewardAddress object.
Returns TransactionBuilder
The builder instance for chaining.
- Defined in txBuilder/TransactionBuilder.ts:883

`Static`create

create(
config: { params: ProtocolParameters; slotConfig: SlotConfig },
): TransactionBuilder
Creates a new transaction builder instance.
Parameters
- config: { params: ProtocolParameters; slotConfig: SlotConfig }
  The configuration object for the builder.
  - params: ProtocolParameters
    The protocol parameters for the network.
  - slotConfig: SlotConfig
    The slot timing configuration for the network.
Returns TransactionBuilder
A new, configured TransactionBuilder instance.

Throws
If the native builder instance could not be created.
- Defined in txBuilder/TransactionBuilder.ts:134

Class TransactionBuilder

Index

Properties

Methods

Properties

ptr

Methods

addCertificate

Parameters

certificate: Certificate

Optionalredeemer?: PlutusData

Returns TransactionBuilder

addDatum

Parameters

Returns TransactionBuilder

addInput

Parameters

Optionaldatum?: PlutusData

Optionalredeemer?: PlutusData

utxo: UTxO

Returns TransactionBuilder

addOutput

Parameters

Returns TransactionBuilder

addReferenceInput

Parameters

Returns TransactionBuilder

addScript

Parameters

Returns TransactionBuilder

addSigner

Parameters

Returns TransactionBuilder

build

Returns Promise<string>

Throws

delegateStake

Parameters

poolId: string

Optionalredeemer?: PlutusData

rewardAddress: string | RewardAddress

Returns TransactionBuilder

delegateVotingPower

Parameters

drepId: string

Optionalredeemer?: PlutusData

rewardAddress: string | RewardAddress

Returns TransactionBuilder

deregisterDRep

Parameters

drepId: string

Optionalredeemer?: PlutusData

Returns TransactionBuilder

deregisterStakeAddress

Parameters

Optionalredeemer?: PlutusData

rewardAddress: string | RewardAddress

Returns TransactionBuilder

expiresAfter

Parameters

Returns TransactionBuilder

Example

expiresIn

Parameters

Returns TransactionBuilder

Example

getRefCount

Returns number

lockLovelace

Parameters

amount: number | bigint

Optionaldatum?: Datum

scriptAddress: string | Address

Returns TransactionBuilder

lockValue

Parameters

datum: Datum

scriptAddress: string | Address

value: Value

Returns TransactionBuilder

`Optional`redeemer?: PlutusData

`Optional`datum?: PlutusData

`Optional`redeemer?: PlutusData

`Optional`redeemer?: PlutusData

`Optional`redeemer?: PlutusData

`Optional`redeemer?: PlutusData

`Optional`redeemer?: PlutusData

`Optional`datum?: Datum

`Optional`redeemer?: PlutusData

`Optional`governanceActionId?: GovernanceActionId

`Optional`governanceActionId?: GovernanceActionId

`Optional`governanceActionId?: GovernanceActionId

`Optional`governanceActionId?: GovernanceActionId

`Optional`governanceActionId?: GovernanceActionId

`Optional`policyHash?: string

`Optional`redeemer?: PlutusData

`Optional`redeemer?: PlutusData