---
title: Modules
sidebar_label: Modules
---

import Tabs from "@theme/Tabs";
import TabItem from "@theme/TabItem";

ZMK makes use of [Zephyr modules](https://docs.zephyrproject.org/3.5.0/develop/modules.html) to include additional source code or configuration files into its build. You can think of them as similar to plugins or themes. The most common uses of this feature are:

- Building firmware for a keyboard external to ZMK's tree
- Adding functionality to ZMK, such as a driver or a behavior

A common ZMK setup thus consists of the following separate components, commonly housed in their respective Git repositories:

- A single ZMK config maintained by the user, containing the `.conf` and `.keymap` files for one or multiple keyboards. This is also where files from ZMK or modules should be overridden/modified, if there is a need.
- Any number of ZMK modules, maintained by the module's owner. Some modules may contain multiple keyboards or functionalities. If all of your keyboards and functionalities are internal to ZMK's tree, then no modules are necessary.
- The ZMK firmware itself, maintained by its contributors.

:::note
The shift to using modules for keyboards is a relatively recent one, and not all designs may be properly configured to be used as a module. If this is the case for your keyboard, then we would strongly suggest asking your vendor or designer to rectify this.
:::

## Building With Modules

### GitHub Actions

When [using GitHub Actions to build ZMK](../user-setup.mdx), adding modules is as simple as modifying the `west.yml` found in your `zmk-config`'s `config` directory. The recommended way of doing so is:

1. Find the URL base (the parent URL) for the module and add it as an entry to the [remotes](https://docs.zephyrproject.org/3.5.0/develop/west/manifest.html#remotes).
2. Add the module as an entry to the [projects](https://docs.zephyrproject.org/3.5.0/develop/west/manifest.html#projects).
   Aside from the mandatory `name`, `remote`, and the commonly used `revision` properties, take note of the `import` property under `projects`. Some modules may have other modules as dependencies. This property allows the specifying of an additional west manifest file found in the tree of the module, which will automatically import all dependencies.

For more information on `west.yml`, see [West Manifests](https://docs.zephyrproject.org/3.5.0/develop/west/manifest.html).

#### Examples

<Tabs
defaultValue="zmk"
values={[
{label: 'Default', value: 'zmk'},
{label: 'Module A', value: 'ma'},
{label: 'Modules A + B', value: 'mab'},
]}>
<TabItem value="zmk">

```yaml
manifest:
  remotes:
    - name: zmkfirmware
      url-base: https://github.com/zmkfirmware
  projects:
    - name: zmk
      remote: zmkfirmware
      revision: main
      import: app/west.yml
  self:
    path: config
```

</TabItem>
<TabItem value="ma">

```yaml
manifest:
  remotes:
    - name: zmkfirmware
      url-base: https://github.com/zmkfirmware
    - name: module_a_base
      url-base: https://github.com/alice
  projects:
    - name: zmk
      remote: zmkfirmware
      revision: main
      import: app/west.yml
    - name: module_a
      remote: module_a_base
      revision: main
  self:
    path: config
```

</TabItem>
<TabItem value="mab">

```yaml
manifest:
  remotes:
    - name: zmkfirmware
      url-base: https://github.com/zmkfirmware
    - name: module_a_base
      url-base: https://github.com/alice
    - name: module_b_base
      url-base: https://github.com/bob
  projects:
    - name: zmk
      remote: zmkfirmware
      revision: main
      import: app/west.yml
    - name: module_a
      remote: module_a_base
      revision: main
    - name: module_b
      remote: module_b_base
      revision: main
      import: west.yml
  self:
    path: config
```

</TabItem>
</Tabs>

### Building Locally

To add a module to your build when building locally, you will need to clone/copy said module into your local file tree. You can then build using the module as described in [Building with External Modules](../development/local-toolchain/build-flash.mdx#building-with-external-modules).

## Beta Testing

You may find that there are some features which you desire for which there is a [Pull Request](https://github.com/zmkfirmware/zmk/pulls), but no module. If this is the case, you can still make use of the feature.

### Developer Repositories and Branches

For a developer to submit a pull request to ZMK, they must first clone the original ZMK repository. After they have a copy
of the source code, they may create a feature branch to work within. When they have finished, they will publish the feature
branch and create the pull request.

#### Finding the repository page from the Pull Request

![PR Repository](../assets/features/beta-testing/pr-repo-branch.png)

#### Finding the repository URL

![Repository URL](../assets/features/beta-testing/repo-url.png)

#### Finding the repository branch

![Repository URL](../assets/features/beta-testing/repo-branch.png)

## Testing Features

### GitHub Actions

When [using GitHub Actions to build ZMK](../user-setup.mdx), once you have obtained the correct URL, you'll need to modify the `west.yml` file similarly to [Building With Modules](#building-with-modules). Add the remote for the branch like in said section. The difference is that you will need to change the selected remote and revision (or branch) for the `zmk` project.

#### Example

<Tabs
defaultValue="zmk"
values={[
{label: 'Default', value: 'zmk'},
{label: 'Alternative', value: 'alt'},
]}>
<TabItem value="zmk">

```yaml
manifest:
  remotes:
    - name: zmkfirmware
      url-base: https://github.com/zmkfirmware
  projects:
    - name: zmk
      remote: zmkfirmware
      revision: main
      import: app/west.yml
  self:
    path: config
```

</TabItem>
<TabItem value="alt">

```yaml
manifest:
  remotes:
    - name: zmkfirmware
      url-base: https://github.com/zmkfirmware
    - name: forkedzmk
      url-base: https://github.com/forkedzmk
  projects:
    - name: zmk
      remote: forkedzmk
      revision: specificpr
      import: app/west.yml
  self:
    path: config
```

</TabItem>
</Tabs>

### Building Locally

When building from a pull request locally, you'll need to [perform the local user setup](../development/local-toolchain/setup/index.md), but using the repository of the pull request rather than the official ZMK repository. You can then [build and flash](../development/local-toolchain/build-flash.mdx) as usual.
