swaitsandClaude Opus 5.5
c9810ea0a3
Three spec decisions from Stephen (2026-10-13), raised by the spec-blind test writers, each test-first: - A payment dated before its invoice or bill is refused (PaymentBeforeDocument); a real prepayment is a deposit. Test: a_payment_never_predates_its_document. Replay is unaffected (it goes through replay_invoice_payment / replay_bill_payment). - Aging as of a date shows only documents issued by then, less only the payments made by then. The ledger now records each document's payment entries (live and on replay), and aging counts those dated by as_of. Test: aging_as_of_a_date_sees_only_what_existed_then; the A/R and A/P conservation properties' aging oracles updated to the confirmed rule (they had assumed aging ignored dates). - A schedule through a mid-month date prorates that month by days; the code was right and its doc wrong. The spec-blind test that disagreed is rewritten to the confirmed spec and no longer ignored. Also found while wiring payments: a payment to an unknown cash account created the payment's draft and then failed, leaving it behind; the cash account is now checked before anything is created. The unreviewed golden van_schedule.json is gone: every row was first checked against an independent hand computation (all 61 matched), then replaced by van_schedule_is_the_hand_computed_one, which asserts that computation directly (548.39, 59 x 1,000.00, 451.61; total 60,000.00). Tests: 452. No spec-disagreements left ignored. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01GWVo7x3UHw5kwCUaWxiejX
Specification sources
wanderbooks' rules come from documents, not from anyone's memory. This
directory holds the authorities the engine's specs cite (docs/spec/rules.md
is the rule catalog), and every spec block in the code carries a SOURCE:
line pointing into it.
The authority stack
There is no single "bible" of US bookkeeping. Authority is layered, and the layers differ in what they cover and in whether we may copy them:
| Layer | What it governs | Copyright | Here |
|---|---|---|---|
| Pacioli (1494), Geijsbeek translation (1914) | The mechanics of double entry: debits equal credits, the trial balance, one money, writing only forward, correcting by opposite entry, closing into capital. No modern standard restates these; they predate every regulator. | Public domain | Vendored verbatim: sources/pacioli-1494.md |
| IRS: Internal Revenue Code, Treasury Regulations, publications, form instructions | Records and supporting documents, retention, accounting periods and methods, information returns (1099), capitalization (de minimis, 12-month rule), partners' capital, payroll taxes, rounding on returns | Public domain (17 U.S.C. §105; IRS.gov's content policy) | Vendored verbatim: sources/irs-*.md, sources/us-public-domain-status.md |
| FASB Accounting Standards Codification (ASC) | Authoritative US GAAP: cash flows (ASC 230), revenue and principal vs agent (ASC 606), foreign currency (ASC 830), credit losses and aging (ASC 326), property and depreciation (ASC 360) | © Financial Accounting Foundation | Cited by paragraph with short quotes only (in rules.md) |
| FASB Concepts Statement No. 8, Chapter 4 (2021) | Definitions of the five elements (it replaced Concepts Statement 6) | © Financial Accounting Foundation; non-authoritative | Cited with short quotes only |
| Textbooks (OpenStax Principles of Accounting, Vol. 1) | Conventions no standard states: normal balances, closing-entry mechanics, straight-line depreciation arithmetic | CC BY-NC-SA 4.0 (incompatible with this repo's license) | Cited with short quotes and attribution only |
| Convention or decision | Where no authority speaks: aging bucket edges, cent rounding among members, closed-period locks | — | Stated as CONVENTION or DECISION, with who decided and when |
How to read a SOURCE line
SOURCE: Pacioli ch. 36 (sources/pacioli-1494.md); IRS Pub. 583 (sources/irs-records.md)
SOURCE: ASC 830-20-30-1 (cited, rules.md B-3)
SOURCE: DECISION (Stephen, 2026-10-13)
SOURCE: CONVENTION (QuickBooks aging); nearest authority ASC 326-20-55-38 (illustrative)
A rule whose only source is CONVENTION or DECISION is a candidate for a human to confirm or overturn; nothing else is.
Rules added later never lock out older books
When a rule is tightened (a check added to a command), books written
before it must still open. Journal replay and the SQLite cross-check read
history through the engine's replay_* commands, which skip checks added
later; new commands go through the checked ones. Pinned by
books_written_under_older_rules_still_open (ledger-store).
Vendoring rules
- Public-domain texts are copied verbatim (whitespace normalized), each with its URL, retrieval date, and the SHA-256 of the retrieved file, so anyone can check the excerpt against the original.
- Copyrighted sources are cited by paragraph, quoted briefly, never copied.
- When an authority changes (the IRS revises a publication; a statute is amended), add the new text beside the old with its effective date. Rules that depend on dates (1099 thresholds) must say which text applies when.
- Rules that change with the law are registered in
crates/ledger-core/src/rules.rswith the years they are known for and a review date. Past what it knows, the engine refuses rather than guesses; from the review date, the MCP digest and the viewer flag the rule. Whoever updates one (human or agent) vendors the new official text here, extends the rule, and sends the change upstream: a pull request at https://github.com/swaits/wanderbooks (best), or an issue.
Open: sources we could not verify
Read on 2026-10-13 through Deloitte's free DART roadmaps, which reproduce ASC text: ASC 230-10-45-16 and -28, 326-20-55-37/38, 606-10-25-23, 45-2, 55-37/38, 830-20-30-1. Not yet verified (the ASC's free basic view needs a login): ASC 360-10-35-4 (depreciation), 340-10 (prepaids), 230-10-45-10, 606-10-55-37B, 210 (balance sheet). Until someone with a FASB basic-view account reads them, the rules that would cite them cite the textbook and say so.