Doing the books

Three everyday jobs

Each clip below is the real app, about three seconds long.

Send an invoice

Choose a customer, add the lines, post it.

Prices can include GST or have it added
Save it as a draft, or put it in the books now

A line typed in, with the totals working as you go.

Code the bank statement

Drop in a CSV from your bank. ByteBook suggests an account for each line, and you confirm it.

Enter the closing balance and it checks the books against the statement
Lines are skipped if you import the same file twice

One line coded. The waiting count drops.

Work out GST

Pick a period. The return fills in from your transactions.

Every box traces back to the entries behind it
Save a snapshot before you file, so it can be checked later

A different period, worked out from the ledger.

Proving the books

Four things a spreadsheet cannot do

Run the assurance checks

Sixteen procedures run on the real entries every time you open the page. Each one reports what it found and gives you a working paper.

Ledger integrity, double entry
Bank, debtors, creditors, GST reconciliation
Manual journals, duplicate payments, cut-off, documents, expenses
Sealed packs, access, and a recalculation of the reports
Whether anything is missing from the record, and who entered, voided and worked out of hours

Exceptions first, then what is fine.

Check the record has not changed

Every entry carries a fingerprint that includes the one before it. Change an old number and the chain shows it.

Voiding a mistake does not break the chain. Editing the original does
Verify the whole chain, or click one entry to read it

Nineteen entries, verified link by link.

Seal a period

Seal a month or a GST period. The fingerprint covers every entry and figure inside it.

Verify it later to prove the period has not moved
Backdating an entry into a sealed period fails the check

Sealed, with a fingerprint you can quote.

Hand it to somebody who checks it themselves

Each time the record is verified, ByteBook writes down what it said: how many entries, the last fingerprint, and the root of the whole ledger. Keep the receipt.

A receipt is two dozen lines you can email to your accountant. Paste it back in later and ByteBook says whether the books still match it
Export the whole record with a script that recomputes it: Python 3.8, nothing else installed, no internet, no ByteBook
A read-only key lets an auditor's own tools read the same figures, and every read is written to an access log

The audit bundle page: what the folder holds, the three commands an auditor runs, and the read-only API — The record, a script that checks it, and a key to read it with.

For training

A real business to practise on, already trading

Twelve of them ship with the application. Open one and the books are months old: invoices sent and chased, a bank statement coded, GST filed, one or two mistakes that somebody had to fix. Each has a paragraph on what it teaches and four things to try. Nothing you do in one can touch a client's records.

Choosing a business, and what each one is for.

Business	GST	Return	What it practises
Bright Cuts hairdressing	No	—	Books with no GST anywhere
Kōwhai Advisory consulting	Yes	Monthly, payments	A late payer, and GST that follows the money
Tasman Builders construction	Yes	2-monthly, invoice	Stage payments on one contract
Harbour Cafe hospitality	Yes	Monthly	Daily takings banked in a lump, and a deposit that covers more than one day
Loom & Light online retail	Yes	2-monthly	Refunds that reverse a sale
Marine Parade Rentals property	Yes	2-monthly	Rent that carries no GST, and repairs you cannot claim it on
Whirinaki Contracting horticulture	Yes	6-monthly	A long return period
Foundry Labs software	No	—	Costs only, no revenue yet
Marine Parade Dental health	Yes	Monthly	Passwords and four roles
Ngata Plumbing trades	Yes	2-monthly	A busy bank statement
Pacific Trading wholesale	Yes	6-monthly	Imports, and a balance date that is not 31 March
Precision Engineering engineering	Yes	2-monthly	Amounts that break careless rounding

Your books stay yours

A practice business is a separate set of books kept beside your own. Choosing one opens it; Back to my books opens yours again, and a line across the top of every page says which one you are looking at. Work you do is kept until you start over.

Built by running them

Each practice business is produced by driving the real application through a year of that trade and then checking the books from the raw rows. One command does it for all twelve, which is also how the program is tested.

Four roles

Owner, general manager, accountant, auditor. The last two can read everything and change nothing. Adding a role needs the owner's password.

And your own books, from a file

Open a bytebook.db — a backup from another machine, or a set of books somebody sent you — as its own business, leaving everything else where it is.

Teaching

Built to be taught.

ByteBook is a teaching tool as much as a bookkeeping app. The books are real, the mistakes are real, and every rule behind the work is named.

A year of books to start from

Twelve New Zealand businesses, each months into trading. Students open one and start where the work already is.

A handbook that shows its sources

Twenty-three chapters, from invoices and GST to assurance and working papers. Every citation is checked against the standard it came from.

The software process, on screen

Invoices, bank statements, GST returns, reports, roles and the audit trail: the same screens a bookkeeper works in.

Open to New Zealand universities, educators and small businesses

We welcome universities and small businesses that want to use ByteBook for teaching and training. If you teach accounting information systems, or the accounting software process, we are open to licensing ByteBook for your course.

Tell us what you want to teach and we will help you get started.

Get in touch about teaching Read the handbook

Standards

Every rule behind the handbook is named

So you can check it yourself.

117standards held, each with a file fingerprint

71references in the handbook, all checked against the publisher's text

3IAASB Handbook volumes

23chapters

Where they come from

New Zealand's accounting and auditing standards, published free by the External Reporting Board, and the IAASB Handbook, published free by IFAC.

What we publish

References, and short quotes with the paragraph named. Not the standards themselves — they stay with their publishers, and the link goes to them.

All 71 references and their sources →

The handbook

Read it here

Twenty-three chapters. Turn the page, or open it on its own.

Chapter Open the full handbook →

Use the arrows to turn the page. Every citation opens the standard, the paragraph and the document it was checked against. The whole book on one page prints to a clean PDF.

Install

Choose your computer

The same books, reports and audit trail. The macOS build is signed and notarized; the first Windows build is an unsigned beta.

macOS

Apple Silicon, macOS 12 or newer. Drag ByteBook into Applications. Signed with ByteMind's Apple Developer ID and notarized by Apple.

Download for macOS 35 MB · no administrator password

Windows Beta

Windows 10 version 1903 or newer, or Windows 11, on a 64-bit PC. Microsoft .NET Framework 4.8 is included with those versions. The installer adds Microsoft's Edge WebView2 Runtime if the PC does not already have it, and ByteBook falls back to your browser if the runtime cannot be installed. Per-user installer; no administrator rights, service or firewall change.

Download for Windows Unsigned beta · SmartScreen may ask you to confirm · Check the SHA-256

About the Windows beta. There is no Windows code-signing certificate yet, so Microsoft SmartScreen may show “Windows protected your PC”. Choose More info → Run anyway only if the SHA-256 published with the installer matches the file you downloaded. Your books live in %APPDATA%\ByteBook, separately from the application.

Who it is for

Accounting and audit firms training staff on a business that behaves like a real one.
Small businesses that want their books on their own computer.
Universities and educators teaching accounting information systems or the accounting software process. Teaching with ByteBook.

What it does not do

It works out GST from what you code. It does not decide whether a supply is taxable.
It prepares tax working papers. It does not file them.
It reports what is in the books. It does not draw the conclusion.

One SQLite file holds the books. The app listens on 127.0.0.1 only, keys stay in the macOS Keychain or a protected local file on Windows, and the optional assistant is off by default.

Bookkeeping for New Zealand businesses