flowchart LR
    U[Authenticated user] --> F[React and TypeScript interface]
    F --> A[FastAPI boundary]
    A --> P[Authorization and subscription policies]
    P --> S[Python domain services]
    S --> D[(PostgreSQL company data)]
    S --> C[Deterministic calculations and documents]
    T[Pytest, Vitest, audits, and Gitleaks] --> A
    G[Production configuration gates] --> A