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type: index, dev, reference
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# Application Security development documentation
Development guides that are specific to the stages that work on Application Security features are listed here.
Please go to [Application Security](../../user/application_security/index.md) if you are looking for documentation on how to use those features.
## Namespaces
Application Security code in the Rails monolith is organized into the following namespaces, which generally follows
the feature categories in the [Secure](https://about.gitlab.com/stages-devops-lifecycle/secure/) and [Protect](https://about.gitlab.com/stages-devops-lifecycle/protect/) stages.