---
last_verified: 2026-03-16
pattern:
  id: architecture-principles
  name: "Architecture Principles (ECAL)"
  category: governance
---

description: >
  Formalized decision-making principles aligned with Oracle's ECAL framework.
  The skill selects applicable principles based on the workload profile and
  presents them in the proposal as the governance framework for the architecture.

principles:

  design:
    - id: "D-01"
      name: "Operational Simplicity"
      principle: "Keep architecture simple. If still complex, simplify again."
      rationale: "Complex solutions tend to be inflexible, non-agile, and operationally fragile."
      applies_when: "always"

    - id: "D-02"
      name: "Application First (SaaS > PaaS > IaaS)"
      principle: "Always consider application services first, platform services second, infrastructure services as last resort."
      rationale: "Higher-level services reduce operational burden and accelerate delivery."
      applies_when: "always"

    - id: "D-03"
      name: "Use-Case Fit"
      principle: "Map workloads into applicable use-cases. Architectural simplicity and operational success come from re-use."
      rationale: "Custom architectures are expensive to build and maintain. Reference architectures exist for a reason."
      applies_when: "always"

    - id: "D-04"
      name: "Hybrid-Ready"
      principle: "Solution should run in hybrid mode, accounting for network bandwidth and latency."
      rationale: "Most enterprise migrations have a hybrid phase. Architecture must work during transition."
      applies_when: "on-prem exists or migration is phased"

    - id: "D-05"
      name: "HA for Business Continuity"
      principle: "Architect for availability, prepare for disaster, leverage cloud's built-in resilience."
      rationale: "HA is cheaper to build in from day 1 than to retrofit."
      applies_when: "always"

    - id: "D-06"
      name: "Compliance by Design"
      principle: "Consider required compliance requirements and existing policies from the initial design phase."
      rationale: "Retrofitting compliance is orders of magnitude more expensive than designing for it."
      applies_when: "compliance requirements identified (PCI, HIPAA, banking, GDPR)"

  deployment:
    - id: "P-01"
      name: "Automation First"
      principle: "Strive to automate production processes from the beginning — infrastructure as code, seeded features."
      rationale: "Manual processes don't scale, are error-prone, and create key-person dependencies."
      applies_when: "always"

    - id: "P-02"
      name: "Environment Separation"
      principle: "Production always separated from test and dev. Clear lifecycle policy."
      rationale: "Prevents accidental data exposure and configuration drift."
      applies_when: "always"

    - id: "P-03"
      name: "API-Centric Integration"
      principle: "Prefer integration via REST APIs over lower-level network protocols."
      rationale: "APIs are versionable, documentable, and testable. Direct DB links are fragile."
      applies_when: "integration points exist"

    - id: "P-04"
      name: "Data Security at Rest and In Transit"
      principle: "Encrypt data at rest (TDE) and in transit (SQL*Net encryption). Key management from day 1."
      rationale: "Encryption is a baseline, not an option. Key management complexity grows with scale."
      applies_when: "always"

    - id: "P-05"
      name: "Unified Identity Management"
      principle: "All users managed in central identity system. SSO. Federation where applicable."
      rationale: "Distributed identity is a security liability."
      applies_when: "always"

  service:
    - id: "S-01"
      name: "Cloud Monitoring & Management"
      principle: "Map management and monitoring requirements explicitly. Use cloud-native tools first."
      rationale: "Observability gaps become operational crises during incidents."
      applies_when: "always"

    - id: "S-02"
      name: "Issue & Incident Management"
      principle: "Design for service. Adopt incident management with clear ownership, governance, and SLAs."
      rationale: "Without defined escalation paths, incidents become crises."
      applies_when: "always"

    - id: "S-03"
      name: "Solution Lifecycle"
      principle: "Map governance for cloud solution lifecycle. Apply ITIL/ITSM frameworks. Readiness for continuous change."
      rationale: "Cloud evolves constantly. The architecture must evolve with it."
      applies_when: "always"

    - id: "S-04"
      name: "Cloud Onboarding"
      principle: "Setup PoC environment first. Early Customer Success Management involvement."
      rationale: "Hands-on validation before commitment reduces risk and builds confidence."
      applies_when: "customer is new to OCI"
