---
title: Module Creation
sidebar_label: ZMK Module Creation
---

[ZMK modules](../features/modules.mdx) are the recommended method of adding content to ZMK, whenever it is possible. This page will guide you through creating a module for ZMK. Distinction is made between modules used for different purposes:

- Modules containing one or more keyboard-related definitions (boards, shields, interconnects, etc.)
- Modules containing behaviors & features
- Modules containing drivers
- Modules containing visual effects

ZMK comes with a Git repository called `zmk-modules` which tracks various different modules. This allows modules to be discovered and used by various tools and scripts. The below described creation process will guide you through the creation and addition of a module to `zmk-modules`. For a precise description of the requirements, see the `README.md` found in the `zmk-modules` repository.

## Template

ZMK has a template to make creating a module easier. Navigate to [the ZMK module template repository](./new-shield.mdx) and select "Use this template" followed by "Create a new repository" in the top right.

The rest of this page will go through the contents of the template step by step, guiding you through the configuration of the module.

## Zephyr Module File

This is the file that defines your module. Only when this file is configured correctly will your module function as expected.

### Name

First, you will need to name your module. ZMK has a naming convention that you should follow:

```
zmk-<type>-<description>
```

Valid options for type are:

| Type         | Description                                                                                                           |
| ------------ | --------------------------------------------------------------------------------------------------------------------- |
| `keyboards`  | The module contains definitions for one or multiple keyboards, be they boards or shields.                             |
| `components` | The module contains definitions for one or multiple components, such as boards for shields to use.                    |
| `behavior`   | The module contains a single behavior.                                                                                |
| `driver`     | The module contains a single driver.                                                                                  |
| `feature`    | The module contains a single feature which doesn't fall under the other categories.                                   |
| `vfx`        | The module contains definitions for one or multiple visual effects, such as display customisations or RGB animations. |

`<description>` is your choice of name to describe the module. See the names of other modules of your chosen type in the `zmk-modules` repository for examples.

Note that your _module name_ does not have to be the same as your _repository name_. For example, if you have named your module `zmk-keyboards-corne`, you may for your own organisational purposes want to name the repository e.g. `zmk-keyboards-corne-module`.

Your module name goes in the `zephyr/module.yml` file:

```yaml title="zephyr/module.yaml"
name: <your module name>
```

### Build Options

Next, you need to define the options to build your module. These also go into `zephyr/module.yml`, as children of the `build` property. Commonly used options are:

- The `depends` child property is used to specify a list of modules which the module depends on. The dependencies are referred to by their [module name](#module-name).
- The `cmake` child property is used to identify a folder containing a `CMakeLists.txt` used to build the module.
- The `kconfig` child property is used to identify the `Kconfig` used to build the module.
- `settings` is a child property containing additional child properties, two of which are particularly relevant:
  - `board_root` points to the parent directory of a `boards` directory, which contains additional board/shield definitions.
  - `dts_root` points to the parent directory of a `dts` directory, which contains additional devicetree bindings.

See the `zephyr/module.yml` found in the template for a usage example.

## Dependencies

If your module depends on other modules, then you should also define a [west manifest](https://docs.zephyrproject.org/3.5.0/develop/west/manifest.html) file. While the `zephyr/modules.yaml` file defines _which_ modules your module depends on, the west manifest file defines _where_ said modules are found. This then allows automatic tooling to fetch the modules when building firmware.

It is recommended that you place the manifest file at the root of your module, though you can place it elsewhere. Be sure to note in your `README.md` that your module uses dependencies, so that users import these correctly.

```yaml title="west.yml"
manifest:
  remotes:
    - name: remote-name
      url-base: https://github.com/remote-name
  projects:
    # Together with the above defined remote, this refers to a module located at
    # https://github.com/remote-name/repository-name
    - name: repository-name
      remote: remote-name
      # This points to a west manifest file in the remote module for further imports
      import: west.yml
```

See the [modules feature page](../features/modules.mdx) for additional information on using west manifest files.

## Informational Files

Make sure to include a `README.md` file and a `LICENSE` file in your repository. Only modules with MIT-compatible licenses can be added to `zmk-modules`.

## Predefined Files and Folders

The repository comes with a number of files and folders already positioned for you to edit. The below table describes which files are most likely kept and which are most likely deleted, based on your module's type. Note that these aren't hard rules, merely the most common use case. The only rule that needs to be followed is that unused files and folders should be deleted.

| ---------------- | `keyboards` | `components` | `behavior` | `driver` | `feature` | `vfx` |
| ---------------- | ----------- | ------------ | ---------- | -------- | --------- | ----- |
| `board/`         | ✅          | ✅           | ❌         | ❌       | ❌        | ✅    |
| `dts/`           | ✅          | ❌           | ✅         | ✅       | ✅        | ❌    |
| `CMakeLists.txt` | ❌          | ❌           | ✅         | ✅       | ✅        | ✅    |
| `Kconfig`        | ❌          | ❌           | ✅         | ✅       | ✅        | ✅    |
| `include/`       | ❌          | ❌           | ✅         | ✅       | ✅        | ❌    |
| `src/`           | ❌          | ❌           | ✅         | ✅       | ✅        | ❌    |
| `snippets/`      | ❌          | ❌           | ❌         | ❌       | ✅        | ❌    |

The below table reminds of the purpose of each of these files and folders, if you are not already familiar with them:
| File or Folder | Description |
| ---------------- | -------------------------------------------------------- |
| `board/` | This folder contains definitions for boards and shields. |
| `dts/` | This folder contains devicetree bindings and includes. |
| `CMakeLists.txt` | CMake file for the module |
| `Kconfig` | Kconfig file for the module |
| `include/` | Folder to put C header files into |
| `src/` | Folder for C source files|
| `snippets/` | Folder for [snippets](https://docs.zephyrproject.org/latest/build/snippets/index.html)|
