Standards and sources

Most of what Lopifi implements came from somewhere else. This page lists the standards behind the rules, what we take from each, and which claims are our opinion.

If you want to check whether a rule is real, the source is one click away. A model answering a question about money formatting finds the primary source sitting next to our restatementCloseRestatementRevising previously issued statements to correct an error material to them ("Big R") — comparatives are relabeled Restated and the error disclosed of it.

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Currency and number formatting#

Source	What we take
ISO 4217	Currency codes and minor-unit exponents. JPY 0, USD 2, KWD 3. Every Money value carries an ISO 4217 code, so there is no untyped amount in the system.
Unicode CLDR	Locale formatting: separators, symbol position, accounting parentheses. We reach it through Intl.NumberFormat and don't reimplement it.
ECMA-402	The Intl API itself, including currencySign: "accounting" and currencyDisplay: "narrowSymbol", which do most of the work in formatting money.
Unicode U+2212	The minus sign. U+002D, the hyphen, is a different width and breaks a column of deltas.
ISO 8601	Dates on the wire. Displayed dates are localised; transmitted dates never are.

Accounting#

Component behavior follows these standards. The components are not a compliance product, and none of this is accounting advice.

Source	Where it shows up
FASB Accounting Standards Codification	The US GAAPFoundationsUS GAAPGenerally accepted accounting principles in the United States — for nongovernmental entities, the FASB Accounting Standards Codification; for SEC registrants, also the SEC's rules and interpretive releases frame behind statement semantics and schedules.
ASC 606Revenue recognitionASC 606Topic 606, Revenue from Contracts with Customers — five steps: identify the contract, identify the performance obligations, determine the transaction price, allocate it, recognize revenue as each obligation is satisfied / IFRS 15	Revenue recognitionRevenue recognitionRevenue recognitionDeciding when, and how much, revenue is recorded — under US GAAP, when (or as) control of a promised good or service transfers to the customer, at the consideration the entity expects to be entitled to, deferred revenueFoundationsDeferred revenueConsideration received, or unconditionally due, before the goods or services are transferred — a liability until the performance obligation is satisfied. ASC 606 calls it a contract liability and the revenue waterfall.
ASC 842Fixed assets & leasesASC 842Topic 842, Leases — puts nearly every lessee lease longer than twelve months on the balance sheet as a right-of-use asset and a lease liability, classified as operating or finance / IFRS 16	The lease liabilityFixed assets & leasesLease liabilityThe present value of the lease payments not yet paid, discounted at the rate implicit in the lease or, if not determinable, the incremental borrowing rate unwind and ROU amortizationFoundationsAmortizationSpreading the cost of a finite-lived intangible, a prepaid or a debt discount over the periods it serves behind LeaseSchedule and the lease tool.
ASC 830 / IAS 21	Functional versus presentation currencyStatementsPresentation currencyThe currency the statements are shown in. ASC 830 calls it the reporting currency; IAS 21 the presentation currency — we use the latter, translation versus remeasurementStatementsRemeasurementRestating foreign-currency monetary balances, or books kept in a currency other than the functional one, into the functional currency — differences go to the P&L, and CTA — see multi-entity and FX.
COSO internal control framework	Segregation of dutiesControlsSegregation of dutiesSplitting authorization, recording, custody of assets and reconciliation across different people, so no one person can both commit and conceal an error or fraud — at minimum, preparer ≠ approver, approval and evidence, in controls and audit.
ISO 20022	Payment message vocabulary, where our payment states have to map onto a rail.

Interface#

Source	What we hold ourselves to
WCAG 2.2 AA	Contrast, focus visibility, target size, and the rule that no state is signaled by color alone. Financial value colors are checked at grayscale as well as atStatementsAs atThe point-in-time label for a balance sheet ratio.
WAI-ARIA Authoring Practices	Grid, listbox, dialog and disclosure behavior — including correct aria-rowcount under virtualization, which most data grids get wrong.
prefers-reduced-motion	Honored throughout, and testable live from the switch in the showcase header.
OpenType tnum and case	Tabular figures and case-shifted punctuation, on every numeral. See aligning numbers.

Where we are opinionated rather than compliant#

These rules are ours. They're arguments, and no standard backs them:

• Never animating a value a reader might take as the truth. The reasoning is in motion principles.
• Debit and credit as two columns, with no single-column variant. Double-entry doesn't mandate a presentation. We treat the two-column form as a control and don't ship the compact version.
• Three sizes and three weights per component, one accent per view. A house rule, written down so people can argue with it.
• The words we refuse. The lexicon names one term per concept and lists the synonyms we don't use. No standard goes that far.

Any number this site quotes about a third party, such as an API rate limit, a page size or a vendor's minor version, is marked as volatile. Check it against the vendor's own documentation before you rely on it.