> ## Documentation Index
> Fetch the complete documentation index at: https://docs.envzero.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Terragrunt Module Detection

> Detect changed Terragrunt modules in pull requests and limit PR plan execution to only the modules affected by the changes using this env zero plugin.

If you use [Terragrunt run all](/guides/admin-guide/templates/terragrunt/#run-all-terragrunt-command-checkbox) with [PR Plan](/guides/admin-guide/environments/plan-on-pull-request) feature you can use this [plugin](https://github.com/env0/env0-terragrunt-modules-detection-plugin) for running plan only for changed modules in the PR by using this code:

```yaml theme={null}
version: 2
deploy:
  steps:
    terraformPlan:
      before:
        - name: Terragrunt Modules Detection
          use: https://github.com/env0/env0-terragrunt-modules-detection-plugin
```

This will detect which code was changed and based on that will decide which module to run based on the files that were changed as part of the Pull request.

For more information, check out the [Modules Detection Plugin Repository](https://github.com/env0/env0-terragrunt-modules-detection-plugin)

## Next steps

* [Terragrunt Integration](/guides/admin-guide/templates/terragrunt) - Configure Terragrunt templates with run-all support.
* [Running Plan on Pull Requests](/guides/admin-guide/environments/plan-on-pull-request) - Trigger plans automatically from pull requests.
* [Plugins Overview](/guides/integrations/plugins) - Understand how env zero plugins work and how to author your own.