> For the complete documentation index, see [llms.txt](https://note.levelcode.org/software-engineering-notes/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://note.levelcode.org/software-engineering-notes/readme/5-layers/8-infrastructure-layer.md).

# Infrastructure Layer

### Persistence Layer

* Provides implementation of repositories

### Messaging Layer

* Sends and receives message to or from other systems
* Provides implementation for messaging services required by the system

### External Layer

* Provides implementation for other external system