# Set up a company in Luxembourg with Ekwo OS

Ekwo OS is open source software for keeping double-entry books in a database you own. This page is generated from the Luxembourg pack, version 1.9.0; every code on it is read from the pack.

The Luxembourg pack is **community**: contributed, and reviewed by nobody.

> Ekwo is software, not an accountant and not tax advice: a pack is a reading of the rules at the date of its version, and it can be wrong for your situation. Have a qualified professional in Luxembourg check your set-up and your first declarations. See [what Ekwo is, and what it is not](https://ekwo.ai/disclaimer/).

## 1. What you need

- A [Supabase](https://supabase.com) project of your own. The free plan is enough to start; Ekwo does not create it, pay for it or have access to it.
- From its dashboard: the connection string (Connect → **Session pooler**), the Project URL and the `service_role` key (Project Settings → API). The key is used once, to create your first administrator, and is written nowhere. The anon (publishable) key, on the same page, is what you sign in with afterwards.
- Node 20 or later on your machine. Nothing else: no Supabase CLI, no Docker, no clone.

## 2. Install

One command. It asks for the rest as it goes.

```sh
npx ekwo-os init --country LU
```

- One chart of accounts: PCN — plan comptable normalisé, 1026 accounts.
- The books can be kept in `fr`, `de`, `en`; the installer asks. Without a terminal, pass `--language <code>`.
- The Déclaration périodique de TVA (eCDF) is filed on one of these cadences: `month`, `quarter`. Pass `--vat-period <cadence>` to set yours.
- A financial year follows the calendar unless you pass `--fiscal-year-start YYYY-MM-DD`.

The same, with no question asked — every value your own:

```sh
npx ekwo-os init \
  --country LU \
  --language fr \
  --vat-period <month|quarter> \
  --db-url "postgresql://postgres.<ref>:<password>@<pooler host>:5432/postgres" \
  --supabase-url "https://<ref>.supabase.co" \
  --service-role-key "$SUPABASE_SERVICE_ROLE_KEY" \
  --org "Your Organisation" --company "Your Company" \
  --admin-email "you@example.com" \
  --yes
```

## 3. Before you go live

Four settings of your project no installer can reach: turn off self sign-up, keep two administrators, keep the `service_role` key off every other machine, and read the disclaimer. `init` prints them; [the installation guide](https://ekwo.ai/docs/install/#before-you-go-live-four-things-on-your-project) explains each.

## 4. A first invoice

Sign in as the administrator you just created, pick the company, and write a draft. `--dry-run` shows the entry the database would write, and writes nothing; `post` books it.

```sh
ekwo login --supabase-url https://<ref>.supabase.co --anon-key <publishable key> --email you@example.com
ekwo use "Your Company"
ekwo contact add "First Customer" --country LU --ref customer-1
ekwo doc new --contact "First Customer" --ref invoice-1 --line "name=Consulting,price=1000.00,account=7061,tax=LU-S-17"
ekwo post invoice-1 --dry-run
ekwo post invoice-1
```

A line names its account and its tax by code, never by rate. `7061` is the account the pack names for sales; the chart may carry a closer one for what you sell — services, a reduced rate — and `list_accounts` lists them.

What the invoice says about your company — its address, its VAT number — comes from the company’s profile, which the MCP tool `update_company_profile` fills; `ekwo init` sets only the name.

The domestic sale taxes the pack carries today. Which one a sale carries is a question about that sale, for you or your accountant: the list is the pack’s, not advice.

| Tax code | Name | Rate |
|---|---|---|
| `LU-S-17` | Vente 17 % — taux normal | 17 % |
| `LU-S-14` | Vente 14 % — taux intermédiaire | 14 % |
| `LU-S-08` | Vente 8 % — taux réduit | 8 % |
| `LU-S-03` | Vente 3 % — taux super-réduit | 3 % |

## 5. With an AI assistant

The MCP server lets an assistant keep the books as you, under your own row level security, and never with the `service_role` key. [Configuring it](https://ekwo.ai/docs/mcp/), and [what an assistant must and must not do](https://ekwo.ai/docs/agents/).

## What the Luxembourg pack carries

- Charts of accounts: PCN — plan comptable normalisé (1026).
- 35 taxes, at 0 %, 3 %, 7 %, 8 %, 13 %, 14 %, 16 %, 17 %.
- The Déclaration périodique de TVA (eCDF) (`LU-VAT-PERIODIC`), 162 boxes, filed month, quarter.
- Electronic invoices as `peppol-bis-3`.
- Financial statements: Bilan abrégé (eCDF), Compte de profits et pertes abrégé (eCDF).

## What it does not do

- No library of this repository writes the file of the LU-VAT-PERIODIC yet: the return is computed and frozen here, and typed on the administration’s portal.
- No library of this repository reads a `mt940` bank statement yet.
- Nothing is sent to an administration, a Peppol network or a bank by the open source software: transmission is yours, or an operator’s you appoint.
- What the pack leaves out on purpose is in [its README](https://github.com/Ekwo-ai/ekwo-os/tree/main/packs/lu).