Everything you need to run your purchase ledger.
Axiom is a purchase ledger and receipt archive for workshops, trade teams, and UK companies. This manual covers architecture, email routing, validation rules, mobile intake, and accounting exports.
1. Architecture & Data Sovereignty
Physical SQLite Isolation & The Zero-Trust Ledger
Unlike conventional SaaS accounting apps that pool thousands of companies into one massive multi-tenant database table, Axiom assigns every business a physically isolated SQLite database file (data/tenants/{company}/books.sqlite).
"A language model cannot be made incapable of misreading a figure, so nothing in the engine asks it to be right."
Vision models extract candidate strings, dates, and digits from PDFs. All mathematics, VAT splits, tax-point verifications, and sign balances are computed deterministically using integer pence arithmetic (Math.round(val * 100)). Floating-point calculation is strictly forbidden in the ledger.
Your confidential parts margins, trade tier discounts, and supplier pricing are protected under UK GDPR. Customer financial documents are never fed into commercial LLM training corpuses.
Original PDF invoices and camera scans are hashed with SHA-256 for tamper-evident retention. One click exports an HMRC-compliant audit package with original files preserved.
2. Inbound Email Vault Setup
Dedicated Inbound Routing & Fail-Closed Whitelist
Every company is assigned a dedicated virtual inbox handle. Suppliers email invoices directly to your address, or you can configure an automated forwarding rule in Gmail / Microsoft 365.
To prevent spam, unsolicited promotions, and phishing invoices from polluting your ledger, Axiom operates a strict fail-closed inbound policy. An incoming email is accepted only if:
- Owner Address: The sender matches the account owner's email address.
- Custom Domain Rules: The sender domain is explicitly whitelisted in Settings (e.g.
@boc.com,*@tegiwa.com,@supplier.co.uk). - Active Suppliers: The sender email matches any registered supplier's contact or accounts email in your Supplier Directory.
Unauthorized emails are rejected with HTTP 403 and logged under the Blocked tab in the Mailbox view with a direct 1-tap "+ Whitelist Sender" button.
3. The 14 Statutory Validation Rules
Deterministic UK Ledger Verification Engine
Every document is evaluated against 14 statutory checks. A blocker prohibits commitment to the ledger until resolved, while a warning alerts the reviewer to unusual characteristics (e.g. new supplier or foreign currency).
Only enterable commercial purchase documents (invoices, credit notes, receipts) enter the ledger. Non-binding quotes, proformas, statements, and delivery notes are blocked.
Checks the supplier trading name and company number against your own registered entities.
Verifies that net_pence + vat_pence === gross_pence exact to the penny.
Verifies if calculated VAT ratio matches standard UK rates: 20.0% Standard, 5.0% Reduced, or 0.0% Zero/Exempt.
Purchase invoices and receipts must have strictly positive values. Credit notes must have negative values throughout.
Sum of all extracted itemized lines (∑ item.net) must equal invoice net_pence within ±2p rounding tolerance.
Invoice date must be a valid ISO YYYY-MM-DD format, not set in the future, and within HMRC 7-year retention window.
Verifies (supplierKey, invoiceNumber) uniqueness across all non-rejected records in the database.
Checks if an invoice with identical supplier, date, and exact gross amount already exists under a revised reference.
Matches trading name against your registered supplier directory and alias records.
Evaluates the 9-digit or 12-digit UK VAT registration number against HMRC mathematical check digits.
Under UK tax law, Input VAT cannot be reclaimed without a valid supplier VAT registration number.
Checks if a supplier previously registered as non-VAT (vat_registered = 0) is suddenly charging VAT.
Identifies non-GBP currency codes (USD, EUR, JPY, CAD) and flags them for zero-rated UK VAT status.
4. Anomaly Detection & 1-Tap Repairs
Automatic Failure Patterns & Instant Repairs
When an invoice fails arithmetic balance, the engine runs three deterministic heuristics matching common supplier formatting quirks and presents instant 1-tap correction buttons:
detectSwap)Occurs when a supplier prints large "TOTAL" headers at the top of an invoice, causing OCR to capture the Gross total into the Net field.
detectShortNet)Occurs when a supplier prints goods subtotal (e.g. £128.34) and freight charge (e.g. £9.50) separately. Because freight is taxable at 20%, the true net is £137.84.
shortBy = (gross - vat) - net and appends a "Carriage / Delivery charge" line item.detectCompletion)Hardware merchants, trade counters, and retail receipts often print only a gross payable total without itemized VAT breakdown.
net = round(gross/1.2)) or 0% Non-VAT (net = gross, vat = 0).5. Review Queue & Strict Ledger Separation
1-Tap Verification & Safe Commit Boundary
To guarantee pristine financial hygiene, Axiom enforces a hard separation between unreviewed intake and the statutory purchase ledger:
Documents with status needs_review or rejected never appear in the Purchase Ledger, do not increment Supplier Directory spend/counts, and are excluded from CSV/ZIP export bundles.
Clicking Confirm & Next (or pressing Enter) atomically commits the document to the ledger, removes it from the queue, and seamlessly switches the inspector to the next pending invoice.
6. Mobile Floor Scanner & iOS App
Counter Receipts & Instant Shop Floor Intake
Workshop staff can snap counter delivery dockets, tyre receipts, and trade merchant slips directly on their phone by opening cloud.getaxiom.app in Safari or Chrome, or with the Axiom Scan iOS app.
Team members invited in Settings sign in on their phone with a 6-digit email code. No pairing codes or shared shop PINs are needed.
Supports instant photo capture, quick spend category tags, job reference notes, and multi-page receipt uploads directly from the phone camera.
7. Data Sovereignty, Exports & Account Closure
Zero Vendor Lock-in & 1-Click Vault Archive
Axiom believes your financial data belongs strictly to your business. You can export clean accounting files or download your entire physical SQLite database at any second.
Formatted with UK tax points (DD/MM/YYYY), correct nominal expense coding (e.g. 5000 Purchases, 5100 Carriage), and strict CWE-1236 CSV injection protection.
GET /api/export/archive)Generates a complete standalone archive containing:
books.sqlite: The raw, WAL-flushed SQLite 3 database file.purchase_ledger.csv: Complete reconciled purchase ledger.suppliers.csv: Complete directory of trade suppliers and VAT numbers.receipts/: All original high-resolution PDFs and scans sorted bySupplier/YYYY/MM/.manifest.json: Cryptographic checksums and record counts.
Owners can permanently purge their account in Settings. Typing your exact company name triggers an atomic wipe: closes database connections, recursively deletes physical disk files (rm -rf data/tenants/{id}), and cascades deletions across system records.
8. Desk Keyboard Shortcuts
High-Speed Verification & Queue Navigation
Review hundreds of monthly supplier invoices without touching your mouse:
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