Hello,

Reusable themes, patterns and templates should be kept in the foundation layer.

As they can be used for multiple applications.

For better understanding of 3 layer architecture refer to the link provided below.

https://success.outsystems.com/documentation/best_practices/architecture/designing_the_architecture_of_your_outsystems_applications/the_architecture_canvas/?_gl=1*19rgh71*_ga*NzAzMzEwNTU0LjE2NTg2NDI1NDc.*_ga_ZD4DTMHWR2*MTY5NDg4OTAyMy4xODUuMS4xNjk0ODg5MTgxLjU2LjAuMA..

Thanks 

Anees

Hello Minh,

Themes, Patterns and Templates should be always considered as Foundation Modules. Simply because they are agnostic to be business and are high reusable between apps.

For more information, check this documentation.

Kind regards,

Rui Barradas

Hi Minh Quang Nguyen

The Theme, Patterns, and Templates are placed and included in the foundation layers. but always remember that you must use the relevant naming convention. because OutSystems use the naming to place it in the specific layers.

Hope this will help you.