Lesson 1 · Foundations · Both · 20 min
What a Core Banking System Really Is
CBS as system of record: products, customers, accounts, and the transactions that bind them.
Objectives
- ▸Define CBS responsibilities vs channels and middleware
- ▸Separate customer, account, and product concepts
- ▸Explain why posting integrity beats UI speed
- ▸Identify typical integration surfaces for fintechs
A Core Banking System (CBS) is the authoritative ledger for customer balances and bank books. Channels (mobile, branch, UPI) and fintech apps are clients. If the core and the app disagree, the core wins for legal balance—and partner banks will remind you of that.
- Customer / party master: who the bank knows.
- Products: savings, current, loan, term deposit templates.
- Accounts: instances of products with balances and status.
- Transactions: postings that change balances under rules.
Key terms
CBSSystem of recordProduct parameterEODMiddleware