# Service Integration

`TxBuilder` can be integrated with services to streamline transaction building.

### Evaluator

{% hint style="success" %}
Integration is completed
{% endhint %}

The evaluator service provided helps perform redeemer execution unit optimization, returning an error message in case of an invalid transaction.

### Fetcher

{% hint style="info" %}
Integration is not live yet
{% endhint %}

The fetcher service helps with auto-completing missing information in transaction building by fetching information from the blockchain. Affected APIs are `tx_in`, `tx_in_collateral`, `spending_tx_in_reference`.

### Submitter

{% hint style="info" %}
Integration is not live yet
{% endhint %}

The submitter service provides alias function(s) for handy transaction submission.