# Using Helmfile

Atmos natively supports opinionated workflows for [Helmfile](https://github.com/helmfile/helmfile). Helmfile provides a declarative specification for deploying helm charts.

For a complete list of supported commands, please see the Atmos [helmfile](/cli/commands/helmfile/usage) documentation.

## Stack Configuration

The schema for configuring Helmfile components in Atmos stacks:

```yaml
components:
  helmfile:
    # the slug of the component
    nginx-ingress:

      # configuration specific to atmos
      metadata:
        type: real
        component: nginx-ingress

      # Settings for integrations
      settings: {}

      # Variables passed to Helmfile
      vars:
        installed: true
        namespace: ingress
        chart_version: "4.0.0"

      # Environment variables
      env:
        HELM_DEBUG: "true"
```

### Attributes

- **`vars` (optional)**

  Variables passed to Helmfile. These are deep-merged and made available to your Helmfile configuration.

  **Example:**
  ```yaml
  vars:
    installed: true
    namespace: ingress
    replica_count: 3
  ```
- **`metadata` (optional)**

  The `metadata` section extends functionality of the component. See [Common Component Attributes](/stacks/components#metadata-attributes) for details.

  **Example:**
  ```yaml
  metadata:
    type: real
    component: nginx-ingress
    inherits:
      - ingress-defaults
  ```
- **`settings` (optional)**

  Free-form map for integration configuration.
- **`env` (optional)**

  Environment variables to set when running Helmfile commands.

  **Example:**
  ```yaml
  env:
    HELM_DEBUG: "true"
    KUBECONFIG: "/path/to/kubeconfig"
  ```

## Example: Provision Helmfile Component

To provision a helmfile component using the `atmos` CLI, run the following commands in the container shell:

```shell
atmos helmfile diff nginx-ingress --stack=ue2-dev
atmos helmfile apply nginx-ingress --stack=ue2-dev
```

where:

- `nginx-ingress` is the helmfile component to provision (from the `components/helmfile` folder)
- `--stack=ue2-dev` is the stack to provision the component into

Short versions of the command-line arguments can be used:

```shell
atmos helmfile diff nginx-ingress -s ue2-dev
atmos helmfile apply nginx-ingress -s ue2-dev
```

## Example: Helmfile Diff

To execute `diff` and `apply` in one step, use `helmfile deploy` command:

```shell
atmos helmfile deploy nginx-ingress -s ue2-dev
```