The patterns in this repository are domain-agnostic. The "ledger + settlement saga + strangler modernization" shape recurs across regulated, high-stakes industries. Only the nouns change.
| This repo's concept | Banking / Payments | Healthcare / Claims | Asset Management / Private Equity | Retail / Restaurant |
|---|---|---|---|---|
PaymentPosted (double-entry) |
Payment / card posting | Claim adjudication line | Trade / position movement | Settlement of order / payout |
| Settlement SAGA + compensation | Funds settlement across rails | Claim -> payer -> provider workflow | Trade lifecycle (match, clear, settle) | Order capture -> fulfillment -> refund |
| Compensating reversal | Payment reversal / chargeback | Claim adjustment / void | Trade bust / correction | Refund / void |
| Event-sourced audit log | Reg-mandated transaction history | HIPAA-auditable claim trail | SEC/audit trade reconstruction | Financial close / dispute evidence |
| Strangler Fig + ACL | Mainframe (COBOL/IMS) exit | Legacy claims platform exit | Legacy OMS/portfolio system exit | Legacy ERP / POS modernization |
| Transactional outbox CDC | Core banking -> data platform | EHR/claims -> analytics | Book of record -> risk/analytics | POS -> data lake |
| Canary + SLO auto-rollback | Zero-downtime core releases | Safe releases on PHI systems | Trading-hours-safe deploys | Peak-season-safe releases |
Every one of these industries is mid-migration off legacy systems-of-record. The hard part is never the new code; it is migrating a system-of-record safely, reversibly, and auditably while it stays online. This repo is a concrete, runnable demonstration of exactly that discipline.