Payment Integrations

Executive Summary

Payment Integrations defines the architecture context for payment providers. Payment providers process external payment activity while Billing owns Algosure billing, entitlement, subscription, invoice, and payment-state interpretation.

Why This Exists

Payment integrations are high-impact and require strong security, idempotency, audit, error handling, retry, and provider authority boundaries.

Owner

The owner is the Chief Product Officer and Enterprise Architect.

Business Value

Payment integrations enable subscription billing, invoice payment, entitlement activation, refund handling, and commercial operations.

Payment Integration Flow

sequenceDiagram
    participant Billing as Billing Domain
    participant Gateway as Integration Gateway
    participant Provider as Payment Provider
    participant Events as Event Layer
    participant Audit as Audit Data

    Billing->>Gateway: Request payment provider interaction
    Gateway->>Provider: Execute approved payment action
    Provider-->>Gateway: Return payment result or status
    Gateway-->>Billing: Return normalized payment observation
    Billing->>Events: Publish billing-owned event
    Gateway->>Audit: Record provider interaction

Payment Responsibilities

Area	Owner
Payment processing, settlement, refunds, disputes, provider availability	Payment provider.
Plans, subscriptions, invoices, payment state, entitlements, limits, renewals	Billing Domain.
Provider connectivity, credentials, retries, callbacks, normalized results	Integration Gateway.
High-impact commercial approval policy	Billing, Administration, and security governance.

Payment Integration Rules

Rule	Requirement
Provider controls settlement	Algosure records payment state but does not control external settlement.
Billing owns accepted payment facts	Payment observations become Algosure facts only after Billing accepts them.
Idempotency is mandatory	Payment commands, callbacks, retries, refunds, and state updates require idempotency design.
Audit is mandatory	Payment interactions require tenant, organization, actor, correlation, provider, result, and failure audit.
Secrets are protected	Provider credentials and webhook secrets remain in approved secrets management.
Errors are explicit	Failed, pending, disputed, refunded, and unknown states must be distinguished.

Non-Implementation Boundary

This document does not select payment providers, define payment APIs, webhook signatures, event names, settlement rules, or refund workflows.