End of last year we launched ABAP Cloud and the new ABAP extensibility guide for SAP S/4HANA: 

We are really impressed how many SAP S/4HANA customers have read the ABAP extensibility guide and directly started using ABAP Cloud and the 3-tier-extensibility model. We had intensive sessions with many of these ABAP Cloud early adopters and learned a lot about ABAP Cloud usage in real SAP S/4HANA systems. 

Now the time has come to share this collected learning with you.  

We provide an updated version of our ABAP extensibility guide. Additionally, we publish more detailed information about ABAP Cloud use cases and how to mitigate missing SAP APIs in SAP S/4HANA Cloud, private edition or on-premise.  

Here is your guide how to consume this comprehensive ABAP Cloud and ABAP extensibility rollout package:
The ABAP extensibility guide is the best starting point if you want to get an overview about ABAP extensibility and ABAP Cloud. The activity log on page 1 allows you to easily access the updated chapters in version 2 of this document.
For the other documents we recommend to start with the level 1 overview blogs and then get all the details in the level 2 documents. Finally the links and documents:

UPDATED VERSION OF THE ABAP EXTENSIBILITY GUIDE 

Main updates (see the activity log on page 1): 

• ABAP Cloud for analytics use cases. 
• Recommendations for business configuration apps (SAP Fiori apps versus SM30 based apps). 
• Setup and interplay of the tiers in the 3-tier-extensibility model. 
• ABAP Cloud governance: ABAP Test Cockpit (ATC) recommendations for the 3-tier extensibility model. 

Extend SAP S/4HANA in the cloud and on premise with ABAP based extensions – version 2.0  

ABAP CLOUD UPDATE 

• Level 1: The ABAP Cloud map – What are the main components of ABAP Cloud and how do they interact?
  ABAP Cloud – What does it comprise?    
• Level 2:  A comprehensive reference of technical ABAP Cloud development use cases including links to documentation and guidance when to use the classic ABAP or the ABAP Cloud development model:
  ABAP Cloud –    Technical use cases and recommended technologies   

3-TIER EXTENSIBILITY MODEL UPDATE (SAP S/4HANA CLOUD PRIVATE EDITION AND ON-PREMISE) 

• Level 1: How to mitigate missing released SAP APIs in SAP S/4HANA Cloud, private edition, and SAP S/4HANA:
  ABAP Cloud – How to mitigate missing released SAP APIs in SAP S/4HANA Cloud, private edition and SAP S/4HANA – The new ABAP Cloud API enablement guide | SAP Blogs  

• Level 2: The blog post above introduces the new ABAP Cloud API enablement guide:
  ABAP Cloud API Enablement Guidelines for SAP S/4HANA Cloud, private edition, and SAP S/4HANA 

• Level 2: ATC variant and ATC process recommendation for the 3-tier extensibility model:
  How the ABAP Test Cockpit supports you to adopt ABAP Cloud | SAP Blogs 

This is a big step forward to sharpen the ABAP Cloud story line.  

We will continue our ABAP Cloud collaboration projects with customers and partners and we plan to regularly share these new learnings via new ABAP Cloud updates.

In addition, you can always use our ABAP Cloud FAQ or the community to get your ABAP Cloud questions answered.