Bank transactions and receipts, matched automatically — encrypted in your own browser, no cloud account.
Le Space Belege matches payments to receipts, books crypto in euros at the day’s rate and exports a DATEV package every month. The books stay in your browser, sealed with your passkey.
- €0 · no subscription
- AGPL-3.0
- no server for your data
Still early: keep your statements and receipts somewhere else as well.
What Le Space Belege is, and what it is not
No cloud, no account, no server holding your data. The rest is craft.
- 01
Open source (AGPL-3.0)
Every line of code is open; anyone can check what happens to your data. App and bridge live on GitHub, every release with a changelog.
- 02
No cloud
Your books live encrypted in your browser. Le Space runs no server for them. Every record and every receipt file is sealed with keys derived from your passkey.
- 03
The Safe
Multiple passkey slots: the same passkey on any device, in any browser, and your books are back at once. A second passkey, say a security key in a drawer, gets a slot of its own and opens the same books and every backup.
- 04
Native crypto
Kraken, Bitcoin, EVM, Cosmos, Monero: in euros at the day’s rate with its source, matched like bank payments, in the DATEV export.
- 05
AI only on a click
Your own model: local with Ollama, Qwen for instance, or in an attested enclave (TEE) such as LibertAI’s, whose proof the bridge checks before every connection. Text leaves redacted, every request carries the ✦ mark, and tokens and cost are listed per day, month and receipt. Le Space runs no AI.
- 06
DATEV & free
SKR 03 with BU keys, one ZIP per month including all receipt PDFs, travel expenses as a numbered statement. Free of charge, free software.
Collect, match, export
Three steps, every month. Nothing leaves your computer except the ZIP you hand on yourself.
- 1
Collect
Bank transactions arrive through Hibiscus, Enable Banking or as a CAMT.053 file; crypto from Kraken and your own wallets. Receipts come from the accounting mailbox, uploads, a folder, customer portals or Paperless-ngx. A small bridge on 127.0.0.1 does what a browser is not allowed to.
IMAP · FinTS · CAMT.053 · xpub · IBC - 2
Match
Every receipt scores points against every payment: amount, invoice and customer number, IBAN, vendor, date. Sure pairs are linked; the rest become questions on the home page. Own transfers, bank fees and refunds need no receipt. “Why this match?” explains every link.
sure from 90 points · candidate from 50 · at most 3 suggestions - 3
Export
One ZIP per month: the DATEV batch (EXTF) for your bookkeeping, every receipt as a PDF with its number, a statement per account and an overview for people. Only once every booking has a confirmed account.
DATEV_2026-09.zip · EXTF_Buchungsstapel_2026-09.csv
What lives where, and who can read it
The short answer: in your browser, and only you. The long answer is the threat model, linked below.
- Passkey instead of a password
- At every unlock the passkey answers once; every key is derived from that answer, anew each time. No key is stored, and the private key never leaves the authenticator.
- Stored locally
- The books live in this browser’s IndexedDB, every record sealed on its own (AES-GCM) and every log entry once more as a whole. Not even the databases’ names say what they hold.
- No cookies, no tracking
- Neither this site nor the app sets cookies or loads anything from third parties. Fonts and code come from the same address as the page.
- The network under your hand
- A badge in the app’s header shows what is online. One click pauses everything; own devices and the invoicing app switch on and off one by one.
- The bridge on 127.0.0.1
- Bank, mailbox, language model and exchanges are reached by a small bridge on your own computer. It listens on 127.0.0.1 only, keeps its secrets in the system keychain and opens mailboxes read-only.
- Backup, sealed
- If you choose, the app backs everything up as one sealed file on Aleph Cloud. Only the same passkey opens it, not even Aleph. The envelope is public: whoever knows the CID can fetch the file, but not read it.
Every movement in euros, with quantity, rate and source
A crypto account holds exactly one asset and has a ledger account of its own. Every booking carries the exact quantity, the rate of its day and where that rate came from, so the valuation can be decided differently later.
0.0042 BTC → 412,08 € · CoinGecko · SKR 03 / 1200
Sources
- Kraken, read-only
- Bitcoin by xpub, ypub or zpub
- EVM: Ethereum, Base, Arbitrum One, OP Mainnet, Polygon
- Cosmos: Nym, Akash, with IBC
- Monero from your wallet’s own export, read in the browser
- Filecoin with USDFC
Rates
- the value of one unit at 00:00 UTC of that day
- CoinGecko, Kraken or the ECB; a DEX pool at the booking’s block
- the other side of a trade, or by hand
Recognised
- own transfers across accounts, chains and bridges
- DEX swaps, token migrations and dust
- network and exchange fees, on their account
Which rate and which valuation method apply (FIFO, average cost, year-end valuation) is the tax adviser’s call. Belege records quantity, rate and source so that any decision can be applied.
Every line open, under AGPL‑3.0
App, bridge and documentation live in one repository. Whoever wants to know what happens to the data reads it, instead of trusting.
- App and bridge on GitHub, a changelog with every release
- Unit, end-to-end and bridge tests run on every push
- Bugs and wishes as issues on GitHub, open to everyone
- The crypto ledger format is MIT-licensed and openly documented
Hosted on IPFS, and you can check that
- There is no server of ours behind the app: the release run on GitHub publishes the build’s IPFS hash (CID) in its summary.
- The domain points at exactly that CID through DNSLink.
dig TXT _dnslink.belege.le-space.dehas to show the CID from the release, andhttps://<CID>.ipfs.inbrowser.link/serves the same build with no domain in between, byte for byte. - With your own IPFS node (Kubo) or the IPFS Companion extension your browser fetches the app straight from the network; then not even the visit is logged anywhere. This is optional.
Do it yourself, or have it done
For small businesses and the self-employed, including those who hold or spend crypto assets: income in coins as well as expenses in utility tokens, say for Filecoin, Akash, Aleph or NymVPN services. The monthly DATEV package goes to your bookkeeping software or your tax adviser; the actual posting happens there.
We set Le Space Belege up with you: bridge, bank access, accounting mailbox, customer portals, your own language model. And we build adaptations: further blockchains and exchanges, special cases, and the automation of business processes, such as invoicing straight into the books over UCEP. This is a paid service; the app itself stays free.
Le Space Belege is tailored to the German market today: SKR 03, VAT, DATEV. The pattern carries further, since receipts, payments and a monthly package for the bookkeeping exist everywhere. For adapting it to other countries and tax systems, we are looking for partners.
Write to us belege@le-space.deBelege against bookkeeping from the cloud
Both end in a DATEV export. The difference is who reads along on the way.
| Merkmal | Le Space Belege | Cloud SaaS |
|---|---|---|
| Where the books live | in your browser, sealed | on the provider’s servers |
| Account | none; a passkey | e-mail, password, often 2FA |
| Who can read your receipts | only you | the provider and its processors |
| Price | €0, no subscription | a monthly fee per client |
| Source code | open, AGPL-3.0 | closed |
| Crypto | Kraken, wallets, day’s rate with source | rarely, or as an add-on |
| AI | your model, only on a click, redacted | the provider’s models, in the background |
| Offline | yes, the app is a PWA | no |
| If the provider stops | the app keeps running, the code stays | export while you still can |
In fairness: a cloud service takes backups off your hands. With Belege they are yours, with a second passkey and the sealed backup on Aleph.
What people want to know before the first start
Is it really free?
Yes. Le Space Belege is free software under AGPL-3.0, with no subscription and no per-client fee. What costs money is what you choose yourself: your own language model, if you use one, and the credits for a backup on Aleph Cloud, if you make one.
Where is my data?
In your browser, in this site’s IndexedDB, every record sealed on its own. Le Space runs no server for it and sees none of it. What leaves your computer is your decision: the monthly ZIP, a sealed backup on Aleph, and redacted text to the model you set up yourself.
What happens if I lose my passkey?
With a single passkey that is not synced, the books are lost, and so is every backup: it stays on Aleph, but nothing can open it any more. Hence the Safe: under Settings → Keys a second passkey gets a slot of its own and opens the same books. A passkey in iCloud Keychain or the Google Password Manager travels with you anyway. The app says so while only one passkey is registered. Books have to be kept for eight to ten years in Germany, so: a second passkey, and regular backups.
Which banks and sources work?
German banks through Hibiscus (FinTS) via the bridge, banks across Europe through Enable Banking with your own application, and any bank that provides CAMT.053 statements (Revolut or GLS, say) directly in the browser. Company credit cards as accounts of their own from the issuer’s CSV. Receipts from an IMAP mailbox, uploads, a folder, customer portals and Paperless-ngx; e-invoices (XRechnung, ZUGFeRD) are read without AI.
What is the bridge, and do I have to install it?
A small program on your own computer, started with pnpm bridge from the repository. It does what a browser is not allowed to: bank (FinTS), mailbox (IMAP), exchanges, wallets and the language model. It listens on 127.0.0.1 only, keeps secrets in the system keychain, and is paired once with a code. Quite a lot works without it: importing CAMT.053, uploading receipts, matching, exporting.
Does an AI see my receipts?
Only when you click, and only the model you set up yourself. Recommended: a local model with Ollama or LM Studio, Qwen for instance, so nothing leaves your computer. If setting that up is too much: a model in a confidential enclave (TEE) such as LibertAI’s, Qwen as well; the bridge checks the enclave’s attestation before every connection and follows none that has been swapped. With any hosted model the bridge first redacts names, IBANs, addresses and more; that limits what leaves, it does not make a text anonymous. Every call is listed with model, duration and tokens in the history, the cost in the statistics. Le Space runs no AI.
Does it replace my tax adviser?
No. Belege is pre-bookkeeping: it collects, matches, suggests SKR 03 accounts and BU keys for you to confirm, and hands over a DATEV package every month. The VAT overview is a help for the advance return, not the return itself. Valuing crypto, the year-end accounts and what belongs on which account remain your tax adviser’s work.
Does it run on my phone?
Yes, the app is a PWA. The same books on phone and computer after a passkey proof, over public relays, a relay in your own bridge, or by QR code with no relay at all on your own network. The QR code in this page’s header opens the app on your phone.
Which browser do I need?
A current browser and a password manager with PRF support: Chrome, Safari or Firefox with iCloud Keychain, Google Password Manager or 1Password, say. Without PRF Belege opens no data, and the app tells you so at the first start.