add aur package to doc

Author: NikolasK-source

docs/index.md

@@ -134,10 +134,16 @@ By additionally enabling the option ```--bash```, the output is created as a bas
 
 ## Install
 
+### Using the Arch User Repository (recommended for Arch based Linux distributions)
+The application is available as [stdin-to-modbus-shm](https://aur.archlinux.org/packages/stdin-to-modbus-shm) in the [Arch User Repository](https://aur.archlinux.org/).
+See the [Arch Wiki](https://wiki.archlinux.org/title/Arch_User_Repository) for information about how to install AUR packages.
+
+
 ### Using the Modbus Collection Flapak Package: Shared Memory Modbus (recommended)
 [SHM-Modbus](https://nikolask-source.github.io/SHM_Modbus/) is a collection of the shared memory modbus tools.
 It is available as flatpak and published on flathub as ```network.koesling.shm-modbs```.
 
+
 ### Using the Standalone Flatpak package
 The flatpak package can be installed via the .flatpak file.
 This can be downloaded from the GitHub [projects release page](https://github.com/NikolasK-source/stdin_to_modbus_shm/releases):