ATC (ABAP Test Cockpit)ATC
What it is
SAP's static-analysis framework that runs check variants over your code. The `ABAP_CLOUD_DEVELOPMENT_DEFAULT` variant is the authoritative gate for cloud/Clean-Core readiness — it flags every unreleased dependency and disallowed construct.
Why it matters for Clean Core
ATC is the single source of truth for 'how clean is my core?'. A migration is, concretely, the work of driving the ATC cloud-readiness findings to zero. No other tool is the official gate.
Common pitfall
Mistaking a passing local syntax check (or abaplint) for an ATC pass. abaplint is a great fast pre-check, but only ATC with the cloud variant on the target system is authoritative for released-API findings.