ABAP, DDIC, and the enhancement framework translated into X++ and Chain of Command
How the SAP ABAP development stack — the Repository, DDIC, transport requests, user exits, BAdIs, and enhancement points — maps to D365's X++ metadata model, extension-only development philosophy, Chain of Command, deployable packages, and Azure DevOps ALM; with honest comparisons of where the two platforms are genuinely similar and where they diverge.
What you will be able to do
Map SAP DDIC objects (domains, data elements, tables, structures) to their X++ equivalents
Explain why D365 prohibits overlayering and describe the Chain of Command pattern that replaces it
Translate a SAP BAdI implementation to a D365 Chain of Command extension
Describe the D365 ALM pipeline from development to production and compare it to SAP transports
Identify which SAP enhancement types are most directly analogous to D365 event handlers versus Chain of Command
Introduction
ABAP developers moving to D365 are in the fortunate position of being closer to the target than any other functional practitioner on the programme. Both SAP and D365 are metadata-driven platforms where the application layer and the data model are defined in the same repository.
The ABAP stack: DDIC, transport requests, and program types
SAP's ABAP Data Dictionary (DDIC), accessed via transaction SE11, is the metadata repository for every table, field, domain, and data element in the system. The layered structure is:
The SAP enhancement framework: exits, BAdIs, and enhancement points
SAP provides three generations of extensibility, each with different technical characteristics.
D365 development fundamentals: X++, extensions, and Chain of Command
X++ is D365's development language. It is object-oriented, similar in syntax to C# and Java, and compiles to .NET IL. Developers work in Visual Studio with the D365 developer tools extension.
ALM, environments, and deployment
D365 uses a cloud-first ALM model. Development environments are dev boxes — Azure VMs or local VMs running D365 in a single-user mode. Code is written and compiled locally, committed to a Git repository, and built by an Azure DevOps pipeline that produces a deployable package.
Security, reporting, and tooling
D365 security uses a three-tier hierarchy: roles → duties → privileges. A privilege is the lowest-level access grant, equivalent to a SAP authorisation object check result (allow/deny a specific operation on a specific object). Duties group privileges into job-function packages (equivalent to SAP composite roles).
Knowledge check
Summary
ABAP developers will find D365 development structurally familiar: metadata-driven, object-oriented, table-and-class-based, with formal transport/deployment lifecycle management. The decisive difference is the no-overlayering rule.