About the author
Added an About the author page and a byline on every page. Fixed the desktop header, where the Reference menu overlapped the Search button at common screen widths.
Site framework and design system
Built the site framework: navigation, search, light and dark themes, the fact and citation system, glossary tooltips and diagram components. First pages: Payment rails (introduction), Core banking system architecture and Messaging and streaming.
Complete first edition
Added High-volume systems, Build versus buy (with a decision scorer), Limitations and known problems, Regulators and mandates, the RBIReserve Bank of India. India's central bank. It regulates banks and payment systems, runs RTGS and NEFT, and holds the accounts in which banks settle with one another. ecosystem with a relationship map and eleven institution pages, and glossary search. Every fact on the site is now verified against an opened source.
Architecture section
Published all nine architecture topics: core banking, payments, API-first and open banking, event-driven design, data, legacy modernisation, security, multi-data-centre and disaster recovery, and hybrid cloud. Each has diagrams, trade-offs, failure modes and design-review questions. Added what RBIReserve Bank of India. India's central bank. It regulates banks and payment systems, runs RTGS and NEFT, and holds the accounts in which banks settle with one another.’s 2023 IT governance Direction actually requires for disaster recovery: banks define their own recovery targets, aim for near-zero data loss on critical systems and run half-yearly drills.
Fact ledger and corrections
Built the sourced fact ledger. Corrected the cheque clearing section: RBIReserve Bank of India. India's central bank. It regulates banks and payment systems, runs RTGS and NEFT, and holds the accounts in which banks settle with one another. postponed Phase 2 of continuous clearing on 24 December 2025 and changed the session hours. Updated the UPIUnified Payments Interface. NPCI's real-time system for paying from a bank account with a UPI ID, QR code or phone number, through apps on a phone. headline figure to August 2026.
Technologies section
Published all twelve technology topics, from core banking platforms and databases to machine learning and payment-specific technology, each with a landscape table, guidance on choosing, trade-offs, pitfalls and design-review questions. Added RBIReserve Bank of India. India's central bank. It regulates banks and payment systems, runs RTGS and NEFT, and holds the accounts in which banks settle with one another.’s 2025 rules for authenticating digital payments, and noted that RBI’s guidance on AI and model risk is still in draft.
Home, Core systems and Payment rails
Published the full Payment rails and Core systems pages and rebuilt the home page. New: a gross-versus-net settlement example, a step-by-step UPIUnified Payments Interface. NPCI's real-time system for paying from a bank account with a UPI ID, QR code or phone number, through apps on a phone. explainer, UPI limits, the rules for fixing failed payments, card tokenisation, Account Aggregators and a guide to which rail suits which job.