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Moov's mission is to give developers an easy way to create and integrate bank processing into their own software products. Our open source projects are each focused on solving a single responsibility in financial services and designed around performance, scalability, and ease of use.

ACH implements a reader, writer, and validator for Automated Clearing House (ACH) files following the Nacha standards. ACH is the primary method of electronic money movement throughout the United States. The HTTP server is available in a Docker image and the Go package github.com/moov-io/ach is available.

If you're looking for an event driven ACH engine for uploading/downloading files and operations we have built moov-io/achgateway and run it in production. Our article How and When to use the Moov ACH Library will help to generate ACH files for upload to your ODFI.

• Project status
• Usage
  • As an API
    • Docker (Config)
    • Google Cloud (Config)
    • HTTP API (Config)
    • Data persistence
  • As a Go module
  • As a command line tool
  • As an in-browser parser
• OpenAPI SDKs
• Learn about ACH
• FAQ
• Getting help
• Supported and tested platforms
• Contributing
• Related projects

Moov ACH is actively used in multiple production environments. Please star the project if you are interested in its progress. The project supports generating and parsing all Standard Entry Class (SEC) codes and validating files according to the Nacha standards. If you have layers above ACH to simplify tasks, perform business operations, or found bugs we would appreciate an issue or pull request. Thanks!

The ACH project implements an HTTP server and Go library for creating and modifying ACH files. There are client libraries available for both Go and Node/JavaScript. We also have an extensive list of examples of the reader and writer applied to various ACH transaction types.

We publish a public Docker image moov/ach from Docker Hub or use this repository. No configuration is required to serve on :8080 and metrics at :9090/metrics in Prometheus format. We also have Docker images for OpenShift published as quay.io/moov/ach.

Pull & start the Docker image:

docker pull moov/ach:latest
docker run -p 8080:8080 -p 9090:9090 moov/ach:latest

List files stored in-memory:

curl localhost:8080/files

{"files":[],"error":null}

Create a file on the HTTP server:

curl -X POST --data-binary "@./test/testdata/ppd-debit.ach" http://localhost:8080/files/create

{"id":"<YOUR-UNIQUE-FILE-ID>","error":null}

Read the ACH file (in JSON form):

curl http://localhost:8080/files/<YOUR-UNIQUE-FILE-ID>

{"file":{"id":"<YOUR-UNIQUE-FILE-ID>","fileHeader":{"id":"","immediateDestination":"231380104","immediateOrigin":"121042882", ...

To get started in a hosted environment you can deploy this project to the Google Cloud Platform.

From your Google Cloud dashboard create a new project and call it:

moov-ach-demo

Click the button below to deploy this project to Google Cloud.

Note: If you get an error about the image being marked as "Do Not Trust" follow the below steps.

$ cloudshell_open --repo_url "https://github.com/moov-io/ach" --page "shell" --git_branch "master"
Error: You launched this custom Cloud Shell image as "Do not trust".
In this mode, your credentials are not available and this experience
cannot deploy to Cloud Run. Start over and "Trust" the image.
Error: aborting due to untrusted cloud shell environment

cloudshell_open --repo_url "https://github.com/moov-io/ach" --page "shell" --git_branch "master"

go run ./cmd/serverr

In the cloud shell you should be prompted with:

Choose a project to deploy this application:

Using the arrow keys select:

moov-ach-demo

You'll then be prompted to choose a region, use the arrow keys to select the region closest to you and hit enter.

Choose a region to deploy this application:

Upon a successful build you will be given a URL where the API has been deployed:

https://YOUR-ACH-APP-URL.a.run.app

From the cloud shell you need to cd into the ach folder:

cd ach

Now you can list files stored in-memory:

curl https://YOUR-ACH-APP-URL.a.run.app/files

You should get this response:

{"files":[],"error":null}

Create a file on the server:

curl -X POST --data-binary "@./test/testdata/ppd-debit.ach" https://YOUR-ACH-APP-URL.a.run.app/files/create

You should get this response:

{"id":"<YOUR-UNIQUE-FILE-ID>","error":null}

Finally, read the contents of the file you've just posted:

curl https://YOUR-ACH-APP-URL.a.run.app/files/<YOUR-UNIQUE-FILE-ID>

You should get this response:

{"file":{"id":"<YOUR-UNIQUE-FILE-ID>","fileHeader":{"id":"...","immediateDestination":"231380104","immediateOrigin":"121042882", ...

The package github.com/moov-io/ach/server offers an HTTP and JSON API for creating and editing files. If you're using Go the ach.File type can be used, otherwise you can send properly formatted JSON. We have an example JSON file, but each SEC type will generate different JSON.

Examples: Go | Ruby

• Create an ACH file for a payment and get the raw file

By design ACH does not persist (save) any data about the files, batches, or entry details created. The only storage occurs in memory of the process and upon restart ACH will have no files, batches, or data saved. Also, no in memory encryption of the data is performed.

This project uses Go Modules and Go v1.18 or newer. See Golang's install instructions for help in setting up Go. You can download the source code and we offer tagged and released versions as well. We highly recommend you use a tagged release for production.

# Pull down into the Go Module cache
$ go get -u github.com/moov-io/ach

# Show the documentation for the BatchHeader package
$ go doc github.com/moov-io/ach BatchHeader

The package github.com/moov-io/ach offers a Go-based ACH file reader and writer. To get started, check out a specific example:

On each release there's an achcli utility released. This tool can display ACH files in a human-readable format which is easier to read than their plaintext format. It also allows masking DFIAccountNumber values with the -mask flag.

Download the latest release for your computer

$ achcli test/testdata/ppd-debit.ach
Describing ACH file 'test/testdata/ppd-debit.ach'

  Origin     OriginName    Destination  DestinationName       FileCreationDate  FileCreationTime
  121042882  My Bank Name  231380104    Federal Reserve Bank  190624            0000

  BatchNumber  SECCode  ServiceClassCode  CompanyName      DiscretionaryData  Identification  EntryDescription  DescriptiveDate
  1            PPD      225 (Debits Only)  Name on Account                     121042882       REG.SALARY

    TransactionCode   RDFIIdentification  AccountNumber      Amount     Name                    TraceNumber      Category
    27 (Checking Debit)  23138010            12345678           100000000  Receiver Account Name   121042880000001

  ServiceClassCode  EntryAddendaCount  EntryHash  TotalDebits  TotalCredits  MACCode  ODFIIdentification  BatchNumber
  225 (Debits Only)  1                  23138010   100000000    0                      12104288            1

  BatchCount  BlockCount  EntryAddendaCount  TotalDebitAmount  TotalCreditAmount
  1           1           1                  100000000         0

Using our in-browser utility, you can instantly convert ACH files into JSON. Either paste in ACH file content directly or choose a file from your local machine. This tool is particularly useful if you're handling sensitive PII or want perform some quick tests, as operations are fully client-side with nothing stored in memory.

Below are some SDKs generated from the API documentation:

• Node SDK | GitHub

• TODO - OpenAPI Guide

• Official Nacha ACH Guide for Developers
• Intro to ACH
• Create an ACH File
• ACH File Structure
• Balanced Offset Files
• Merging Files

If you have ACH-specific questions, NACHA (National Automated Clearing House Association) has their complete specification for all file formats and message types.

• 64-bit Linux (Ubuntu, Debian), macOS, and Windows
• Raspberry Pi

Note: 32-bit platforms have known issues and are not supported.

Yes please! Please review our Contributing guide and Code of Conduct to get started! Check out our issues for first time contributors for something to help out with.

This project uses Go Modules and Go v1.18 or newer. See Golang's install instructions for help setting up Go. You can download the source code and we offer tagged and released versions as well. We highly recommend you use a tagged release for production.

To make a release of ach simply open a pull request with CHANGELOG.md and version.go updated with the next version number and details. You'll also need to push the tag (i.e. git push origin v1.0.0) to origin in order for CI to make the release.

We maintain a comprehensive suite of unit tests and recommend table-driven testing when a particular function warrants several very similar test cases. To run all test files in the current directory, use go test. Current overall coverage can be found on Codecov.

We currently run fuzzing over ACH in the form of a Github Action. Please report crashes examples to [email protected]. Thanks!

As part of Moov's initiative to offer open source fintech infrastructure, we have a large collection of active projects you may find useful:

• Moov Watchman offers search functions over numerous trade sanction lists from the United States and European Union.

• Moov Fed implements utility services for searching the United States Federal Reserve System such as ABA routing numbers, financial institution name lookup, and FedACH and Fedwire routing information.

• Moov Wire implements an interface to write files for the Fedwire Funds Service, a real-time gross settlement funds transfer system operated by the United States Federal Reserve Banks.

• Moov Image Cash Letter implements Image Cash Letter (ICL) files used for Check21, X.9 or check truncation files for exchange and remote deposit in the U.S.

• Moov Metro 2 provides a way to easily read, create, and validate Metro 2 format, which is used for consumer credit history reporting by the United States credit bureaus.

Apache License 2.0 - See LICENSE for details.