BTP (SAP Business Technology Platform)

Enforces secure, portable, multi-tenant-aware BTP architecture — no hard-coded credentials, no monolithic subaccount designs, no skipped security configurations.

Content Routing

Iron Laws

1. ALWAYS CONSIDER MULTI-TENANCY FROM DAY ONE. Retrofitting multi-tenancy is 3-5x the effort of designing it in. Every BTP solution must document its tenancy model (single vs. multi) before architecture is approved.
2. NEVER HARD-CODE CREDENTIALS. No passwords, client secrets, or connection strings in code, config files, or environment variables set manually. All credentials live in the Credential Store, Destination Service, or Secret Store (Kyma). Hard-coded credentials will be rotated, and your app will break at 2am.
3. ALWAYS USE THE DESTINATION SERVICE FOR BACKEND CONNECTIVITY. Direct URL construction bypasses certificate management, load balancing, and the principal propagation chain. Destination Service is mandatory for all S/4HANA, on-prem, and external system calls.
4. NEVER SKIP XSUAA SCOPE CHECKS. An application that doesn't enforce scopes grants every authenticated user admin-level access. Define roles, role collections, and scopes in xs-security.json before the first protected endpoint is written.
5. NEVER DEPLOY TO PRODUCTION WITHOUT A SEPARATE SUBACCOUNT. Dev / Test / Prod are separate subaccounts, not separate spaces in the same subaccount. Shared subaccounts share entitlements, quotas, and blast radius.

Rationalization Table

Red Flags

• "I'll add the security config later..." → XSUAA scopes are an architecture decision. Define them now.
• "The credentials are just for the PoC..." → PoCs become production. Hard-code once, regret forever.
• "We can use the same subaccount for dev and prod..." → Iron Law 5 violation. Separate subaccounts are non-negotiable.
• "Let me just call the S/4HANA URL directly..." → Iron Law 3 violation. Use the Destination Service.
• "Multi-tenancy isn't needed for this project..." → Document that decision explicitly and get sign-off; don't assume it.

<HARD-GATE> Before any BTP solution design or code: (1) Confirm subaccount landscape (dev/test/prod separation). (2) Confirm runtime choice (CF or Kyma) with documented rationale. (3) Confirm tenancy model. (4) Confirm all credentials will go through Destination Service or Credential Store. No architecture diagram or code until these four decisions are documented. </HARD-GATE>

Subaccount Architecture

Hierarchy: Global Account → Directories (optional grouping) → Subaccounts → Spaces (CF) / Namespaces (Kyma)

Recommended Landscape:

• dev subaccount — developer sandbox, liberal quotas
• test / staging subaccount — integration testing, mirrors prod entitlements
• prod subaccount — production, restricted access, alerting enabled

Entitlement management: Assign service plans per subaccount. Never share entitlements across landscapes by co-locating in one subaccount.

Runtime Decision: CF vs Kyma

CAP Patterns

• `cds.requires` — declare service dependencies, never hard-code in handlers
• `@restrict` annotations — declarative authorization; supplement with req.user.is() in handlers
• Hybrid testing: cds bind --to <cloud-service> for local dev against real BTP services
• CAP + HANA: Use @sap/hana-client via cds add hana; never write raw HANA SQL in handlers
• Multitenancy: Use @sap/cds-mtxs extension; implement onSubscribe and onUnsubscribe handlers

Security Patterns (XSUAA)

Key xs-security.json elements:

xsappname, tenant-mode (dedicated|shared), scopes, role-templates, role-collections

• Principal propagation: Set forwardAuthToken: true in destination for user context forwarding to S/4HANA
• Service-to-service: Use grant-as-authority-to-apps in scopes; bind both apps to same XSUAA instance
• Token exchange: Use TokenExchange grant type for on-behalf-of flows

HANA Cloud Patterns

Key BTP Services Reference

Verification

This skill is complete ONLY when ALL of the following are true:

• [ ] Subaccount landscape documented (dev/test/prod as separate subaccounts)
• [ ] Runtime choice (CF vs Kyma) documented with rationale
• [ ] Tenancy model documented and signed off
• [ ] Zero hard-coded credentials in code or mta.yaml — all via Destination Service or Credential Store
• [ ] xs-security.json scopes defined and reviewed
• [ ] Deployed app responds correctly to authentication + authorization checks (scope enforcement verified)

Evidence required: Architecture diagram showing subaccount structure; xs-security.json with defined scopes; deployment log showing successful bind to XSUAA and Destination Service.

Next Skill

After BTP solution design, invoke: abap-cloud (if ABAP extension) or integration-suite (if integration required) For security review, invoke: security-grc

Related Skills

• abap-cloud — ABAP development on BTP ABAP Environment
• integration-suite — API and integration patterns
• security-grc — Security and authorization review