Ekwo OS

Ekwo OS is free and open source data infrastructure for accounting, finance and tax, under AGPL-3.0: a schema, the rules of each country as data, and tools, for businesses and their accountants. Install it on your own Supabase project and own your accounting data, forever. It is software — not an accounting firm, and not accounting, tax or financial advice (DISCLAIMER.md). Built and maintained by Ekwo. A fully managed edition — your own instance, operated for you, with the AI agents you configure acting on your instructions — is available at ekwo.ai.

An empty Supabase project to a prepared VAT return, for two countries side by side, with the published ekwo-os 0.5.0. How it was recorded, and a longer cut: docs/demo/.

Try it on your own books. Already using Claude? Start with Claude goes from a free Supabase project to your own books taken over, questioned and your next VAT return prepared — Claude Desktop or Claude Code, about twenty minutes — or open the same books in the web application, Ekwo Cloud.

Why Ekwo

The long version — financial autonomy for every business, accounting as a commons, a network rather than a vendor — is in MANIFESTO.md.

Accounting software has settled into two shapes, and both take something from you. The SaaS keeps your books on its servers, behind its API and its price list, and leaving means exporting a PDF. The open-source ERP gives you the code but keeps the parts that save time — bank feeds, automatic matching, invoice recognition — for the paid edition and a network of integrators.

Ekwo is built on a different premise: the data belongs to the business, and the work of keeping the books can be done by software that the business also owns. So the whole accounting core is open, the data sits in a Postgres database that you control, and the interface is designed for machines as much as for people. A REST API and an OpenAPI description come free with Supabase, and an MCP server sits on top of them, so an AI agent can book a purchase, match a payment, prepare a VAT return or produce a FEC on your own data — as you, under your own row level security, without the data ever leaving your account.

What we are building, in order:

1. This repository — the core. Schema, posting rules, VAT, reports, the FEC, and the country packs. Done, tested, installable today.
2. npx -y ekwo-os@latest init — point it at your own Supabase project and it applies the schema, seeds the country rules, creates the first administrator and the first company, in one command. Done; see packages/cli.
3. The MCP server — npx @ekwo-ai/mcp, so any AI agent can operate the books: read the ledger, raise an invoice, post it, match a payment, pull the VAT return or the FEC. Done; see packages/mcp. The web application is Ekwo Cloud, and it opens an instance you run yourself as well as one we host.
4. Any country as a versioned pack of data, with one golden test per country. Every folder of packs/ ships today — the list is under What is in this repository — and more arrive every week. The plan is in docs/international.md.
5. Format libraries as independent MIT packages, in packages/formats/, organised by format and never by country: the French FEC, Factur-X, XBRL for the NBB, the Belgian VAT return, Peppol BIS Billing 3.0, four recapitulative statements and three readers of bank statements — camt.053, CODA and CFONB 120 — exist today; MT940 waits for somebody who needs it.

Who it is for: a company that wants to keep its own books with an AI at the keyboard; an accounting firm that runs several companies inside one installation; a developer who needs a real double-entry core with VAT rules as data rather than as code; and anyone who wants to leave a proprietary system with the books intact.

What we sell, so that this stays free: a managed edition at ekwo.ai where the same schema runs on your own Supabase project, and Ekwo operates the application, the AI agents you set up, the bank connections, the Peppol access point and the channels to the administrations. It is infrastructure, not a service that keeps the books: the books and the filings stay the business's and its accountant's. The Community edition stands on its own, with us or without us, for as long as its owner wants it to. That is the test every feature has to pass before it lands here.

What is in this repository

A double-entry accounting core for Postgres. It is the schema, the posting rules and the reports, as migrations you apply to a database you control. There is no server to run: Supabase turns the schema into a REST API with an OpenAPI description, and row level security decides who sees what.

• Double entry, enforced by the database. Amounts are positive, a reversal flips the side, an entry cannot be posted unless it balances, and a locked period refuses writes at the trigger — not in a form validator.
• Documents and entries are two layers, joined by a foreign key. An invoice answers to EN 16931 and Peppol; an entry answers to the chart of accounts and to the FEC. Keeping them apart keeps both honest.
• Country rules are data. A tax points at the ledger accounts it posts to and at the boxes of the VAT return it feeds. Adding a régime is a row, not a release.
• Every label is data, in every language the country pack publishes. Identifiers and error codes are English and never move; what a person reads is a row. Belgium ships its chart of accounts, its journals, its VAT codes, its declaration boxes and its annual accounts in French, Dutch, German and English, and a company keeping its books in Dutch reads Dutch throughout. docs/languages.md is the mechanism.
• Every country a pack, out of the box. United Arab Emirates (ae), Albania (al), Argentina (ar), Austria (at), Australia (au), Bosna i Hercegovina (ba), Belgium (be), Burkina Faso (bf), България (bg), البحرين (bh), Bénin (bj), Bolivia (bo), Canada (ca), République démocratique du Congo (cd), Centrafrique (cf), Congo (cg), Schweiz (ch), Côte d’Ivoire (ci), Chile (cl), Cameroun (cm), 中国 (cn), Colombia (co), Costa Rica (cr), Cyprus (cy), Czechia (cz), Germany (de), Danmark (dk), Dominican Republic (do), Algérie (dz), Ecuador (ec), Estonia (ee), مصر (eg), España (es), Finland (fi), France (fr), Gabon (ga), United Kingdom (gb), საქართველო (ge), Ghana (gh), Guinée (gn), Guinée équatoriale (gq), Ελλάδα (gr), Guatemala (gt), Guinée-Bissau (gw), Hong Kong (hk), Croatia (hr), Magyarország (hu), Indonesia (id), Ireland (ie), Israel (il), India (in), Ísland (is), Italia (it), 日本 (jp), Kenya (ke), Comores (km), 대한민국 (kr), Қазақстан (kz), Lietuva (lt), Luxembourg (lu), Latvija (lv), Maroc (ma), Moldova (md), Crna Gora (me), Северна Македонија (mk), Mali (ml), Malta (mt), México (mx), Malaysia (my), Niger (ne), Nigeria (ng), Nederland (nl), Norge (no), New Zealand (nz), Oman (om), Panamá (pa), Perú (pe), Philippines (ph), Polska (pl), Portugal (pt), Paraguay (py), Romania (ro), Srbija (rs), Rwanda (rw), Saudi Arabia (sa), Sverige (se), Singapore (sg), Slovenia (si), Slovensko (sk), Sénégal (sn), Tchad (td), Togo (tg), ประเทศไทย (th), Tunisie (tn), Türkiye (tr), 臺灣 (tw), Tanzania (tz), Україна (ua), Uganda (ug), United States (us), Uruguay (uy), Việt Nam (vn), Kosova (xk) and South Africa (za) — each with its chart of accounts, its tax codes, its declaration boxes and its annual accounts, and each installed by ekwo init. The United Kingdom was the first that is not a Member State of the European Union; the United States, with the sales and use taxes of three states and no value added tax, the first without a VAT; Senegal and Côte d'Ivoire the first on the SYSCOHADA chart the OHADA member States share, written once in packs/ohada/. The version and the certification of each are in docs/packs.md.
• The French FEC. Eighteen columns, the arrêté du 29 juillet 2013, with the reconciliation letter and the sub-ledger code the format requires.
• Modules, one Postgres schema each. Fixed assets and budgets ship with this release, in assets and budgets. A module depends on the socle by foreign key, reaches the ledger only through one function, and is enabled per company. The socle ignores its modules.
• Tested on real Postgres. The test suite runs the migrations, the seeds, the accounting scenarios, the installer and the MCP server against Postgres compiled to WebAssembly.

Modules

The socle is public. Beside it, a module is a schema of its own with its own migrations, its own row level security and its own tests.