Based on documentation from NACHA: https://www.nacha.org/system/files/resources/AAP201%20-%20ACH%20File%20Formatting.pdf

{
	"require" : {
		"nacha/file-generator" : "1.9.*"
	}
}

<?php
use Nacha\File;
use Nacha\Batch;
use Nacha\Record\DebitEntry;
use Nacha\Record\CcdEntry;

// Create the file and set the proper header info
$file = new File();
$file->setImmediateDestination('051000033')
	...
	->setReferenceCode('MYCODE');

// Create a batch and add some entries
$batch = new Batch();
$batch->getHeader()
	...
	->setOriginatingDFiId('01021234');

$batch->addDebitEntry((new DebitEntry)
	...
	->setTraceNumber('99936340', 1));

$file->addBatch($batch);

// completed file ready for output
$output = (string)$file;

For complete examples see test/Nacha/FileTest.php

$ ./vendor/bin/phpunit -c test/ci.xml

There is limited validation for field inputs. Strings that are too long will be truncated. Required/mandatory fields are currently not enforced.

Other missing elements:

• Addenda support added in v1.9+
• BOC, ARC, POP Entry records
• Corporate Trade Exchange Entries
• Point of Sale Entries
• Notification of Change Entry (COR)
• Return entries

Support for the above elements should be rather easy to implement, as the models were built with them in mind. Put in a pull request if you have an immediate need for one of the above features.