Platform · Accounting & tax systems

Accounting & tax system

Bookkeeping, accounting and tax preparation software where the books and the returns are read from one ledger, and every figure on a return can be traced back to the documents that produced it.

Request access How it works

DisciplineAccounting & tax

IssuePublic extract

AccessBy invitation

The problem

A wrong number becomes a wrong return.

Books and returns drift apart

Bookkeeping lives in one tool and tax preparation in another, and the figures are carried across by hand.

Rules without sources

Rates and thresholds are typed into code and never traced back to the law that set them, or updated when it changes.

Plausible is not correct

Each part checks itself against its own idea of correct, so two parts can each be consistent and still disagree.

Tests that cannot fail

A test that passes no matter what the code does protects nothing, and nobody finds out until a return is wrong.

Principles

Measured against the law, not against its own idea of correct.

P-1

One way to write to the books

Every entry goes through a single write path that checks it in order before anything is written: balanced, period open, accounts known, chained to the entry before it.

P-2

Money is exact

Amounts are exact decimals, never floating point. Every printed line is rounded where the form prints it, and a half-cent left between two figures is treated as a defect.

P-3

Every statutory figure names its source

A rate, bracket or threshold that changes by year is a table keyed by year, citing the publication and section it was read from. The primary documents themselves are kept with the code.

P-4

Tests proven able to fail

The production code is deliberately broken one defect at a time, and a named test must catch each break. Other tests scan the code for defect shapes that have happened before.

P-5

End to end, by crossings

Real documents run through the real interfaces all the way to the return, and figures produced by two independent engines are required to agree.

P-6

A wrong state cannot be expressed

Where the law has one right answer, the code is shaped so a wrong one cannot be represented: a refund and a balance due are two signs of one difference, so a return cannot show both.

How it works

Documents in, one ledger, returns out.

Invoices, bills, bank activity, payroll and owner contributions go into one double-entry ledger. The trial balance, the financial statements and the returns are read from it, so a figure on a return can be traced back to the documents that produced it.

FIG. 1Source documents reach the books through one write path that checks every entry before it is posted. Statements and returns are read from the ledger, not typed in, and figures from independent engines are required to agree.

Who it is for

Small businesses, the people who own them, and their accountants.

Owner of a single-member LLC

Books kept from invoices, bills and bank activity, the business schedules from those books, and the owner's own return with what is owed and any penalty for underpayment.

S corporation & shareholders

The corporate return compiled from the ledger, a shareholder register of stock blocks each with its own basis, K-1s that split by ownership, and shareholder basis tracking.

An accountant with several clients

Each client as its own company in one installation, a dashboard across all of them, roles and permissions, and period locks the ledger enforces.

What it covers

From the first invoice to the signed return.

S-1

Sell & get paid

Invoices that post when sent, payments and refunds, estimates converted to invoices, retainers, recurring billing, collections, and sales tax charged and remitted.

S-2

Buy & pay

Vendor bills, three-way matching of orders, receipts and bills, one controlled payment path with backup withholding, vendor credits, information returns and inventory at cost.

S-3

Bank & import

Bank feeds and statement files, categorization by rule, reconciliation, receipts booked as expenses, kept source documents, and recurring-spend detection.

S-4

Keep & close the books

Journal entries and reversals, financial statements by class, department and period, fiscal-year close, sealed periods, fixed assets, deferred revenue and subledger checks.

S-5

Payroll

Payroll runs with employer taxes and a per-employee register, quarterly and annual filings, wage statements, garnishments and multi-state rules.

S-6

Business returns

S corporation returns with shareholder K-1s and basis, corporate and partnership returns, supporting forms compiled from the books, and recorded tax payments.

S-7

The personal return

The owner's Form 1040 with the business on Schedule C and self-employment tax, filing status and dependents decided from recorded facts, credits, deductions and what is owed.

S-8

Planning & advice

Entity comparison and S-election, penalties and relief, exchanges and gains, formations and reorganizations, and estate and gift valuation, under the Internal Revenue Code.

S-9

Specialist standards

Leases, the income-tax provision, business combinations, foreign currency and group consolidation, under the relevant accounting standards.

S-10

Clients & migration

Several companies in one installation, invited staff and accountants with permissions, client triage, and migration from existing bookkeeping systems through the same ledger.

Connections

The same ideas, elsewhere in our work.

X-1

By invitation.

Every engagement begins with a conversation and is scoped before work begins. Software, not a tax-preparation service. Nothing on this page is tax advice.

Access

Accounting practices and businesses who want to work with it and shape it.

Subject: Access

Partnerships

Accountants, firms and platforms that serve many small businesses.

Subject: Partnership

Custom builds

Ledger, reporting and statutory engines for your own systems.

Subject: Build

Investment

Briefings and a demonstration, under confidentiality.

Subject: Funding

contact@carbonyl.org