As you already knows, in October Microsoft will launch what is called “Dynamics 365 Business Central Release Wave 2” (platform 15) and some days ago the first public preview was available.
The main “revolution” of this new release is that all is AL only. You will never find CSIDE and C/AL support from now and also no more Windows Client.
Freddy Kristiansen as always has explained all in a great way in these two posts:
I want to add here only two things:
When you go to Extensions Management page in Dynamics 365 Business Central platform 15, you will find two Microsoft’s extensions:
The new extensions that you will create for Dynamics 365 Business Central must be “dependent” from these Microsoft’s apps. When you start a new extension project with Visual Studio Code, you need to add the following lines to your app.json file:
After adding those dependencies, you can download symbols and start working with your new extension:
This is the classical way of work when you develop an extension for the SaaS world (or what I think is the best practice also for the on-premise world).
If you target explicitly the on-premise world, Microsoft permits you to modify the base code (now it’s full AL) and Freddy has well explained how to “extract” the .al files on a local folder and start working on that for creating your new custom BaseApp.
Here I’m directly modifying the Codeunit 80 – Sales-Post:
Code customized AL solutions must be avoided as much more as possible. Giving full access (modifications rights) to the full AL base code is something that must not be intended as “the way to work”. You should go for a code customized AL extension ONLY if your business case cannot be solved in a different way.
Obviously, if you go for a code customized AL extension, you will need to merge objects also in the future (so, please avoid it).