Kladde - AI Bookkeeping for German Freelancers and Small Firms
AI Bookkeeping Platform for a Berlin Startup
Designed and built a clickable AI bookkeeping product for German freelancers, sole traders and small GmbHs: a bank feed with a suggested booking and confidence score on every payment, a receipt inbox that validates e-invoices and checks §14 UStG fields, and a VAT advance return previewed box by box and submitted through ELSTER.
Most of our work is under NDA. Per agreement, we can share the work but not the company details - all names and identifying information shown here have been changed.
Impact
Dashboard, bank transactions, receipt inbox, document detail and VAT return detail, plus the transaction panel, the ELSTER submission panel and the Ask Kladde assistant.
Suggestions from 0.90 show green, 0.60 to 0.89 amber, and below 0.60 grey as "Unsure". Each one names its source - a rule, a learned pattern or the AI model - and gives a one-line reason.
Every supplier invoice is checked for the mandatory fields, with the simplified list for small invoices. XRechnung and ZUGFeRD files are also validated against EN 16931, and the validator's errors are shown.
26 bank transactions, 18 receipts and invoices including 5 e-invoices, 9 monthly VAT returns, 25 SKR03 accounts and 3 bank and cash accounts for one fictional Berlin design studio.
The Problem
Brückstein's target customers kept a shoebox of paper receipts, a folder of PDF invoices in their inbox and a bank app, and once a quarter they or their tax adviser typed it all into a bookkeeping system. Receipts went missing, VAT returns were filed late or estimated, and the adviser spent most of the year-end fee chasing documents and re-booking miscategorised payments. Existing tools assumed an accountant at the keyboard or produced exports the adviser could not trust.
Our Solution
Kladde pulls in bank transactions, suggests a booking account for each one with a confidence score, collects receipts and e-invoices from email, upload and the phone camera, and matches them to payments. From the journal it previews the VAT advance return and submits it through ELSTER, so the owner spends a few minutes a week confirming while the adviser receives books they can review and import into DATEV.
The Challenge: Bookkeeping the Tax Office and the Adviser Both Accept
German small-business bookkeeping has strict rules on how entries are kept, which invoices allow input VAT and when returns are due, and the people doing it are designers and consultants, not accountants.
Books That Cannot Be Rewritten
Under GoBD, entries must be complete, timely and unalterable. A booked entry is corrected with a reversal (Storno) and a new booking, every change is logged, and books are generally kept for 10 years, with accounting vouchers kept for 8 from 2025.
VAT Rules Per Payment
One bank feed mixes 19% and 7% VAT, reverse charge under §13b, EU services, VAT-exempt rent and private shares of a phone bill. Monthly or quarterly advance returns are due by the 10th, or a month later with a permanent extension.
A PDF Is No Longer an E-Invoice
Since 1 January 2025 businesses must be able to receive structured e-invoices in EN 16931 formats such as XRechnung and ZUGFeRD. The XML is the original and must be kept, and an invoice missing a §14 UStG field can cost the input VAT deduction.
AI That Is Not Tax Advice
Tax advice is reserved to tax advisers under the StBerG. The AI may suggest bookings and answer general questions, but it has to show its reasons and sources, say it is not tax advice, and hand individual questions to the customer's Steuerberater.
Our Approach: From German Bookkeeping Rules to a Clickable Product
Spec and Rules Research
Mapped 6 roles from owner and bookkeeper to the tax adviser and their staff, and 42 screens across the business app, the adviser portal and the public and mobile pages. Defined the data model for bank transactions, suggestions, rules, documents, matches, bookings, periods, invoices, VAT returns and a hash-chained audit log. Wrote down the rules the design follows: GoBD, SKR03 and SKR04, EÜR or HGB double entry, ELSTER advance returns, the §19 small business limits from 2025, §14 invoice fields, e-invoicing, retention, StBerG, PSD2 consent and GDPR.
Clickable Demo on a Production UI Kit
Built 5 key screens on a production dashboard kit: the dashboard with to-do cards, KPIs and the next VAT return, the bank feed with status tabs, confidence bars, split chips and bulk confirm, the receipt inbox with format chips and match suggestions, the document detail with the §14 check, VAT ID check and retention date, and the VAT return detail with readiness checks, Kennzahl drill-down and ELSTER submission. All actions run on local state.
What a Production Build Adds
PSD2 bank feeds through a licensed provider such as finAPI or Tink, receipt OCR, e-invoice parsing with Mustang and the KoSIT validator, ELSTER submission via ERiC, DATEV EXTF export, BZSt and VIES VAT ID checks, inbound receipt email and an EU-hosted language model. Also the journal, invoicing, reports, the adviser portal, mobile capture, role-based access, the append-only audit log and legal review of every rule before launch.
Why It Works: The AI Does the Typing, the Owner Confirms
Every Suggestion Explains Itself
A suggested booking shows the account, VAT code, confidence and why, for example 11 earlier Nordhafen Hosting invoices booked to 4806, or rule R-014 splitting off a 20% private share of the phone bill. Low-confidence payments say Unsure instead of guessing, and confirming many at once is one click.
Problems Surface Before They Cost VAT
An e-invoice that fails validation shows a red chip with the first error, a missing §14 field warns that input VAT may not be deductible and offers to request a corrected invoice, and the supplier's VAT ID shows its check result next to the name.
The VAT Return Shows Its Workings
The preview is laid out like the official form, and each Kennzahl opens the bookings behind it. Five readiness checks, a comparison with the previous month and the same month last year, and an authorisation step come before Submit to ELSTER.
Built for GoBD From the First Screen
Originals are stored unaltered with a SHA-256 hash and received time, every document shows its retention date, and submitting a return locks its bookings. Corrections are made with a corrected return, never by editing a locked booking.
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Enterprise Software Engineering - Human + AI
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Location
Global Headquarters
21 Merchant Road, 3rd Floor, Singapore 058267
Main corporate office and leadership operations
North America Office
548 Market Street, PMB 12345, San Francisco, CA 94104
Client operations and business development
India Office
402 Shivalik Shilp II, SG Highway, Ahmedabad 380015
Engineering and delivery center
Enterprise Software Engineering - Human + AI
Contact Us
Locations
Global Headquarters
21 Merchant Road, 3rd Floor, Singapore 058267
Main corporate office and leadership operations
North America Office
548 Market Street, PMB 12345, San Francisco, CA 94104
Client operations and business development
India Office
402 Shivalik Shilp II, SG Highway, Ahmedabad 380015
Engineering and delivery center
© 2026 - Copyright. All Rights reserved Oceanlab