Slowbooks Pro 2026
A personal bookkeeping application raised from the ashes of QuickBooks 2003 Pro.
Free, source-available, and complete: double-entry accounting, unlimited
invoicing, US payroll with tamper-evident tax forms, perpetual inventory,
bank feeds, analytics — with every record in local files you control. No
cloud, no account, no telemetry, no caps, no paid tiers. Multi-user
Server Edition is built into the same signed installer — no Docker
required (Docker remains an optional path for Linux servers).
Get started:
Windows installer ·
macOS DMG ·
Docker / Linux ·
slowbookspro.com ·
🐢 Support SlowBooks Pro
One free product, two shapes: your desktop — or the whole office from one PC.
The Story
I ran QuickBooks 2003 Pro for 14 years for side-business invoicing and
bookkeeping. Then the hard drive died. Intuit's activation servers have
been dead since ~2017, so the software can't be reinstalled. The license
I paid for is worthless.
So I built my own replacement, and transferred my data out of the old
.QBW file using IIF export/import. Early versions wore the grief openly —
the code was annotated with invented "decompilation" comments referencing
QBW32.EXE offsets and Btrieve table layouts as a tribute to software
that served me well until its maker decided it should stop working. The
codebase has since grown up; the last of those comments came out in
v2.14.0, and the fiction now lives only in this origin story. The
software never depended on it.
This is an independent, from-scratch reimplementation. No Intuit
source code or binaries were available, decompiled, or used.
Accessibility
SlowBooks Pro strives to conform to WCAG 2.1 AA: every form field has a
name a screen reader can say, AA contrast in both themes on every page and
dialog, real dialogs, announced notifications, and every generated PDF
tagged (PDF/UA-1) so tax forms read to a screen reader.
Details, known gaps and how to report a barrier:
docs/accessibility.md and
the accessibility page.
What's New
v2.31 — Split expenses, lines that move, and stock that comes back. An
expense splits across several accounts, each line with its own job, cost
code, class and billable mark, and the check stub lists every line (#599);
every line form moves a line up or down, drags it, and inserts one in the
middle (#604); Enter Bill shows the vendor's balance, last bills and
payments and notes beside the form (#601); a register entry takes
attachments (#600). A credit memo's lines take their own class and job
(#640), a return puts the cost back with the quantity, at the original
sale's cost when the memo names the invoice (#641), an item of your own can
carry a negative price as a discount (#639), and a sale past what is on hand
says so, or is refused by a setting (#642). The statements hide zero
balances on request (#625), each piece of a pay run posts to an account you
choose, with net pay able to wait in 2300 Payroll Liabilities (#620), the
job reports read a timestamp on the local day (#644), Cc and Bcc addresses
are read the way a mail program reads them (#611), the Windows installer
replaces the program file on a same-version reinstall (#643), and About
credits the artists from the community art repo (#635).
Patch releases and everything before 2.31 are in CHANGELOG.md.
Wait — it does that?
Cryptographically tamper-evident tax forms. Every W-2, W-3, 940, and
941 PDF carries a SHA-256 content hash and audit ID printed in the
footer. An auditor can recompute the hash and confirm the form hasn't
been edited since generation, against the local document_audits chain.
Not a watermark — a verification trail.
Bring-your-own-AI, including your own gateway. AI Insights runs
against any of eight providers (Anthropic Claude and xAI Grok first, then
Groq, Cloudflare Workers AI, OpenAI, Google Gemini, a Cloudflare Worker you
host yourself, or any OpenAI-compatible endpoint you name) — keys encrypted at rest with versioned, rotatable ciphertext.
And the whole app is agent-operable: every install serves a
self-documenting local REST API (734 operations in v2.31.1) — built for Claude
Code and Grok first, and any agentic CLI works; the
AI setup guide has the paste-prompt.
What stays on your machine is the company file and the API. A cloud-backed
CLI's model does not: what the agent reads from your books goes to its
provider under that provider's terms, and only a model you run locally, and
have checked makes no outbound calls, keeps all of it home. AI Insights has
the same shape — it sends the figures it is given to the provider you chose,
over public HTTPS only.
One-click reseller-permit verification. Per-state format validation
(WA/CA/TX), one click opens the state's official lookup, and the
who-and-when verification trail lands on the customer record.
Boots refuse to lie to you. Dev and debug containers run the
frontend↔backend wiring audit before uvicorn binds the port — drift
between the JS and the routes fails the boot instead of 404-ing
mid-feature. Release images gate on the same check in CI.
What it does
Full catalog in docs/features.md. Highlights:
- Accounts receivable — invoices, estimates, payments with
multi-invoice allocation, credit memos, recurring schedules, batch
payments, Quick Entry for paper backlogs
- Accounts payable — purchase orders, bills, bill payments, vendor
credits, AP aging
- Double-entry core — auto + manual journals, closing-date
enforcement, automatic audit log, 50-account contractor chart
- Banking — the register is the ledger (entries post, feeds are a review queue, reconciliation over ledger lines), transfers, deposits, check printing,
OFX/QFX + Bank of America/Chase/PayPal CSV import with dedup, SimpleFIN and Mercury bank feeds,
shared auto-categorization rules
- Reports & tax — P&L (plain & by Class), Balance Sheet, Trial
Balance, agings, GL, Cash Flow, Sales Tax with pay-to-government flow,
Schedule C, printable PDF pack
- Payroll & HR — full US module with W-2/W-3/940/941, deductions,
garnishments, PTO, onboarding, and a token-accessed employee portal
(docs/payroll-hr-module.md)
- Inventory — perpetual ledger, weighted-average cost, automatic
COGS, reorder points
- Analytics + AI — 8 live metrics, 90-day cash forecast, optional
BYOK insights
- Server Edition — users, roles, attributed audit trail, serves the
office from one PC, built into the same signed installer
(docs/server-edition.md)
- Bank feeds — SimpleFIN: you hold the
bank credential, no middleman server
(docs/setup-bank-feeds.md);
Mercury connects directly with a read-only API token,
with optional signed webhooks for bank balance updates
- Jobs & job costing — Customer:Job on every form, cost codes and
types with burden, time posted at loaded rates, budget vs actual
- Receipt intake — scan a photo or PDF into a Bill, Expense or Sales
Receipt with the OCR built into macOS and Windows (Tesseract on Linux)
Both themes ship in the box — toggle from the topbar or Alt+D; the choice persists.
Server Edition: an edition is a state, not a SKU — add a second user and you've promoted yourself, free either way.
Quick Start
Windows — signed installer
Download SlowBooksPro-Setup-x64.exe
and double-click. Fully self-contained (64-bit Windows 10/11); a portable
.zip is on the releases page
— it needs the Microsoft Edge WebView2 runtime, 101 or later, which Windows 11
has and the installer sets up or updates; without it, or with an older one,
the app says so and offers to open in your browser instead.
Each company is one SQLite file under %LOCALAPPDATA%\SlowBooksPro —
upgrades and even uninstalls never touch your books.
Serve the office (Server Edition): on the host PC, run the bundled
serveredition-install.ps1 from an elevated PowerShell — firewall,
startup task, and machine-wide data location handled. Details in
docs/server-edition.md.
macOS — signed Apple Silicon app
Download SlowBooksPro-macos-arm64.dmg,
drag SlowBooks Pro to Applications, launch. Signed and notarized with
the project's Apple Developer ID on every release; macOS 15+, Apple
Silicon. Intel Macs: Docker.
Docker (Linux servers, Intel Mac)
Docker is optional — multi-user LAN serving on Windows is Server
Edition, built into the signed installer above (no containers involved).
Docker remains the path for Linux servers and Intel Macs:
git clone https://github.com/VonHoltenCodes/SlowBooks-Pro-2026.git
cd SlowBooks-Pro-2026
docker compose up
Open http://localhost:3001 — PostgreSQL, migrations, and seed data
are automatic. The image includes tesseract-ocr and poppler-utils so
receipt scanning works out of the box; native installs add them with
sudo apt install tesseract-ocr poppler-utils (optional — scanning
degrades gracefully when they're absent).
Native installs, demo data, troubleshooting: INSTALL.md.
Backups, restore, key rotation: docs/operations.md.
Production checklist: docs/release-checklist.md.
Documentation
| Doc | Covers |
|---|
| INSTALL.md | Install / first-run / upgrade (installer + DMG + Docker + native) |
| docs/server-edition.md | Serving the office: setup, users & roles, troubleshooting |
| packaging/macos/README.md | macOS maintainer build, signing, notarization runbook |
| docs/features.md | Full feature catalog + API endpoint reference |
| docs/development.md | Tech stack, project structure, contributor flow |
| docs/data-model.md | Database schema |
| docs/operations.md | Backups, restore, key rotation, monitoring |
| docs/payroll-hr-module.md | Payroll / HR module reference |
| docs/release-checklist.md | Production deployment checklist |
| docs/tls-proxy-setup.md | Real certs in front of Slowbooks (Caddy, nginx, Traefik) |
Tech Stack
Python + FastAPI on PostgreSQL (SQLite for tests and desktop companies,
one file each) with SQLAlchemy 2.0 and Alembic. Vanilla HTML/CSS/JS
single-page app — no framework, no build step. WeasyPrint + Jinja2 for
PDFs; self-hosted Chart.js (no CDN, LAN-deployable). Hosted-checkout
payments only — card data never touches the app. Port 3001.
The Windows and Apple Silicon desktop builds freeze the same codebase
with PyInstaller + pywebview. Both sign in CI on every release tag:
Windows via Azure Trusted Signing, macOS with the project's Apple
Developer ID — signed, notarized, and stapled on the runner (signing
credentials live only in repo secrets, never in the repo).
Full layout in docs/development.md.
License
Source-available. Free forever. Yours to self-host. Use it for
yourself or your business, modify it, redistribute it, keep your clients'
books on it. Don't sell it, offer it as a paid service, or build it into
one, in whole or in part. Tools and connectors that talk to it are
welcome, commercial or not. Illinois law. The full terms, version 2.0,
are in LICENSE; the app shows the short form once on first
launch and the Windows installer shows the whole thing. Contributions
come in under the Contributor Terms in CONTRIBUTING.md.
Acknowledgments
- 14 years of QuickBooks 2003 Pro (1 license, $199.95, 2003 dollars)
- Every small business owner who lost software they paid for when
activation servers died
Contributors
Maintainers by platform are in CONTRIBUTING.md. Everyone
who has contributed is credited in the CHANGELOG entry that
shipped their work and in the git history.
