Sources & editorial notes

Scope and audience

This book covers payments and fintech risk engineering with a U.S. focus and global context. It connects payment mechanics, fraud, underwriting, credit, AML, sanctions, compliance, data, models, and operations. Read it in order for the full system, or use the chapter list and search for a specific subject.

The examples explain engineering choices. They are not production policies, legal advice, or an institution-specific compliance program. Legal duties depend on the entity, product, activity, jurisdiction, and facts. Network rules and provider behavior can also differ. Chapters identify those boundaries where they affect the design.

How sources are used

Chapter sources link to regulators, standards bodies, official technical documentation, and provider documentation. Provider examples explain a particular implementation; they are not universal rail rules. Older examination material is read with current rules and agency updates. The original source library was checked on September 17, 2026. The September 18 expansion rechecked key technical and consumer-rule references and added the SciPy reference for binomial intervals.

The edition includes FinCEN’s 2026 beneficial-owner relief, the September 2, 2026 statement on SAR confidentiality and customer communication, Nacha’s 2026 Phase 2 monitoring changes, and the revised federal model-risk guidance in SR 26-2. These dates describe the source edition, not a guarantee that future requirements will remain unchanged.

Original cases and illustrations

Lantern, its customers, and all case records are fictional. Amounts, rates, thresholds, service targets, and stress assumptions are teaching examples unless a passage explicitly identifies an authoritative rule. The 8,000 illustrations include flows, records, ownership graphs, loss curves, confusion matrices, cash ladders, and control failure modes. The 600 worked cases each contain 12 figures and accessible data tables. Analytical forms and some reference data repeat where the same principle applies. They are original vector images, with readable text versions on small screens.

Explanations and diagrams were authored with AI assistance. Automated checks verify structure, links within the book, image coverage, and selected calculations. They do not establish legal accuracy or constitute independent human subject-matter review. No independent human review is claimed.

Corrections and maintenance

Review a correction together with its chapter text, diagrams, glossary terms, source references, and relevant calculations. Record the changed source and effective date. A rule update can affect customer messages, data requirements, and operations as well as the rule itself.

Privacy

The textbook has no accounts, assessments, tracking profile, or analytics integration. Search runs in your browser. The color preference is stored locally. A hosting provider may process ordinary request data when the site is hosted.

Design attribution

The reading interface follows the existing ca-re book and its adaptation of Rubix Documents. The original MIT license is preserved. The interface uses Next.js, shadcn/ui, and Radix. No affiliation with a regulator, payment network, or source publisher is implied.