diff --git a/apps/api/commands/seed_demo.ts b/apps/api/commands/seed_demo.ts
new file mode 100644
index 0000000..0717c71
--- /dev/null
+++ b/apps/api/commands/seed_demo.ts
@@ -0,0 +1,147 @@
+import { BaseCommand, args, flags } from '@adonisjs/core/ace'
+import type { CommandOptions } from '@adonisjs/core/types/ace'
+import db from '@adonisjs/lucid/services/db'
+
+import User from '#models/user'
+import Organization from '#models/organization'
+import Plan from '#models/plan'
+import Client from '#models/client'
+import Invoice from '#models/invoice'
+import ActivityEvent from '#models/activity_event'
+import RelanceTask from '#models/relance_task'
+import CheckinTask from '#models/checkin_task'
+import { provisionDefaultPlans } from '#services/default_plans'
+import { seedDemoOrg } from '#database/factories'
+
+/**
+ * Peuple l'org d'un user existant avec des données de démo réalistes —
+ * pour visualiser dashboard, factures, plans en conditions réelles.
+ *
+ *   node ace seed:demo --email arthurbarre.js@gmail.com
+ *   node ace seed:demo --email ... --reset   # wipe avant
+ */
+export default class SeedDemo extends BaseCommand {
+  static commandName = 'seed:demo'
+  static description = "Peuple l'organisation d'un user existant avec des données de démo (clients, factures, activité)"
+
+  static options: CommandOptions = {
+    startApp: true,
+  }
+
+  @args.string({ description: 'Email du user dont on peuple l\'org', required: false })
+  declare email: string | undefined
+
+  @flags.boolean({
+    description:
+      "Supprime les clients/factures/activité existants de l'org avant le seed",
+    default: false,
+  })
+  declare reset: boolean
+
+  @flags.string({
+    description: "Nom à donner à l'organisation (ex. 'Maçonnerie Dupont'). Si vide, on ne touche pas.",
+  })
+  declare orgName?: string
+
+  async run() {
+    const email = this.email ?? this.parsed.flags.email
+    if (!email) {
+      this.logger.error('Argument requis : --email <user-email>')
+      this.exitCode = 1
+      return
+    }
+
+    const user = await User.findBy('email', String(email).toLowerCase())
+    if (!user) {
+      this.logger.error(`User introuvable : ${email}`)
+      this.exitCode = 1
+      return
+    }
+    this.logger.info(`User trouvé : ${user.fullName ?? user.email} (${user.id})`)
+
+    if (!user.organizationId) {
+      this.logger.error('Le user n\'a pas d\'organization rattachée — flow signup pas terminé ?')
+      this.exitCode = 1
+      return
+    }
+
+    await db.transaction(async (trx) => {
+      const org = await Organization.findOrFail(user.organizationId!, { client: trx })
+
+      if (this.reset) {
+        this.logger.warning('--reset : suppression des clients/factures/activity existants…')
+        // Ordre : enfants d'abord pour respecter les FK
+        await CheckinTask.query({ client: trx })
+          .whereIn(
+            'invoice_id',
+            db.from('invoices').where('organization_id', org.id).select('id')
+          )
+          .delete()
+        await RelanceTask.query({ client: trx })
+          .whereIn(
+            'invoice_id',
+            db.from('invoices').where('organization_id', org.id).select('id')
+          )
+          .delete()
+        await ActivityEvent.query({ client: trx }).where('organization_id', org.id).delete()
+        await Invoice.query({ client: trx }).where('organization_id', org.id).delete()
+        await Client.query({ client: trx }).where('organization_id', org.id).delete()
+      }
+
+      // Configure l'org : nom (si fourni) + bucket volume mensuel
+      const targetName =
+        this.orgName ??
+        (org.name && org.name.length > 0 ? org.name : `Maison ${user.fullName?.split(' ')[1] ?? 'Démo'}`)
+      org.useTransaction(trx)
+      org.name = targetName
+      if (!org.monthlyVolumeBucket) {
+        org.monthlyVolumeBucket = '20-50'
+      }
+      // Reset rubisCount, on le rechargera en fonction des factures seedées.
+      org.rubisCount = 0
+      await org.save()
+      this.logger.info(`Org configurée : "${org.name}"`)
+
+      // Plans : provision si manquants (idempotent)
+      await provisionDefaultPlans(org.id, trx)
+      const plans = await Plan.query({ client: trx }).where('organization_id', org.id)
+      this.logger.info(`Plans disponibles : ${plans.length} (${plans.map((p) => p.name).join(', ')})`)
+
+      // Seed la data
+      const result = await seedDemoOrg({
+        organizationId: org.id,
+        plans,
+        trx,
+      })
+
+      // Met à jour le compteur rubis de l'org en fonction du seed
+      await trx
+        .from('organizations')
+        .where('id', org.id)
+        .update({ rubis_count: result.rubisEarned })
+
+      this.logger.success(
+        `Seed terminé : ${result.clients.length} clients · ${result.invoices.length} factures · ${result.rubisEarned} rubis`
+      )
+
+      // Petit récap par statut
+      const byStatus: Record<string, number> = {}
+      for (const inv of result.invoices) {
+        byStatus[inv.status] = (byStatus[inv.status] ?? 0) + 1
+      }
+      for (const [status, count] of Object.entries(byStatus)) {
+        this.logger.info(`  · ${status} : ${count}`)
+      }
+
+      // User : signature par défaut si vide (utile pour les previews/tests email)
+      if (!user.signature) {
+        user.useTransaction(trx)
+        user.signature = `Cordialement,\n${user.fullName ?? 'L\'équipe'}\n${org.name}`
+        await user.save()
+        this.logger.info('Signature email par défaut posée sur le user.')
+      }
+    })
+
+    this.logger.success('Done.')
+  }
+}
diff --git a/apps/api/database/factories.ts b/apps/api/database/factories.ts
new file mode 100644
index 0000000..9c2bb0c
--- /dev/null
+++ b/apps/api/database/factories.ts
@@ -0,0 +1,382 @@
+/**
+ * Factories — créent des entités réalistes (FR, format Rubis) pour
+ * peupler une org de démo ou alimenter des tests.
+ *
+ * Pas de framework lourd type @adonisjs/lucid factories : des fonctions
+ * pures, idempotentes, qu'on compose dans une commande Ace ou un test.
+ */
+
+import { DateTime } from 'luxon'
+import { randomUUID } from 'node:crypto'
+import type { TransactionClientContract } from '@adonisjs/lucid/types/database'
+
+import Client from '#models/client'
+import Invoice from '#models/invoice'
+import ActivityEvent from '#models/activity_event'
+import type Plan from '#models/plan'
+
+// ---------------------------------------------------------------------------
+// Sources de données déterministes (pas de Faker — moins de deps, plus stable)
+// ---------------------------------------------------------------------------
+
+const CLIENT_TEMPLATES: Array<{
+  name: string
+  firstName: string | null
+  lastName: string | null
+  emailDomain: string
+  phone: string | null
+  address: string | null
+  siret: string | null
+}> = [
+  {
+    name: 'Boulangerie Martin SARL',
+    firstName: 'Marie',
+    lastName: 'Martin',
+    emailDomain: 'boulangerie-martin.fr',
+    phone: '+33 1 23 45 67 89',
+    address: '12 rue du Pain, 75011 Paris',
+    siret: '82345678900012',
+  },
+  {
+    name: 'Maçonnerie Dupont & Fils',
+    firstName: 'Jean',
+    lastName: 'Dupont',
+    emailDomain: 'maconnerie-dupont.fr',
+    phone: '+33 4 78 56 12 34',
+    address: '45 chemin des Carrières, 69100 Villeurbanne',
+    siret: '53412987600028',
+  },
+  {
+    name: 'Atelier Durand',
+    firstName: null,
+    lastName: null,
+    emailDomain: 'atelier-durand.fr',
+    phone: null,
+    address: null,
+    siret: null,
+  },
+  {
+    name: 'Cabinet Rousseau Conseil',
+    firstName: 'Julien',
+    lastName: 'Rousseau',
+    emailDomain: 'cabinet-rousseau.fr',
+    phone: '+33 4 56 78 90 12',
+    address: '8 place de la République, 69002 Lyon',
+    siret: '53412987600101',
+  },
+  {
+    name: 'Garage Lemoine',
+    firstName: 'Pierre',
+    lastName: 'Lemoine',
+    emailDomain: 'garage-lemoine.fr',
+    phone: '+33 2 99 87 65 43',
+    address: '23 boulevard de la Liberté, 35000 Rennes',
+    siret: '78912345600054',
+  },
+  {
+    name: 'Studio Lefèvre',
+    firstName: 'Camille',
+    lastName: 'Lefèvre',
+    emailDomain: 'studio-lefevre.com',
+    phone: null,
+    address: null,
+    siret: null,
+  },
+  {
+    name: 'Restaurant Le Beauvoir',
+    firstName: 'Sophie',
+    lastName: 'Beauvoir',
+    emailDomain: 'le-beauvoir.fr',
+    phone: '+33 1 45 22 33 44',
+    address: '15 rue Mouffetard, 75005 Paris',
+    siret: '12345678900078',
+  },
+  {
+    name: 'Imprimerie Henri & Fils',
+    firstName: 'Henri',
+    lastName: 'Petit',
+    emailDomain: 'imprimerie-henri.fr',
+    phone: '+33 5 61 78 90 23',
+    address: '7 avenue Jean Jaurès, 31000 Toulouse',
+    siret: '45123789600041',
+  },
+]
+
+const INVOICE_NOTES_POOL = [
+  'Prestation conseil — janvier',
+  'Travaux de rénovation second œuvre',
+  'Photographe événementiel — mariage',
+  'Maintenance trimestrielle',
+  'Livraison matières premières',
+  'Audit comptable annuel',
+  null,
+  null,
+]
+
+// ---------------------------------------------------------------------------
+// Factories
+// ---------------------------------------------------------------------------
+
+export type ClientFactoryInput = {
+  organizationId: string
+  trx?: TransactionClientContract
+  /** Index 0..N dans CLIENT_TEMPLATES, sinon valeurs random. */
+  index?: number
+}
+
+export async function makeClient(input: ClientFactoryInput): Promise<Client> {
+  const tpl =
+    input.index !== undefined
+      ? CLIENT_TEMPLATES[input.index % CLIENT_TEMPLATES.length]!
+      : CLIENT_TEMPLATES[Math.floor(Math.random() * CLIENT_TEMPLATES.length)]!
+
+  const inboxName = tpl.firstName
+    ? `${tpl.firstName.toLowerCase()}@${tpl.emailDomain}`
+    : `compta@${tpl.emailDomain}`
+
+  return Client.create(
+    {
+      organizationId: input.organizationId,
+      name: tpl.name,
+      email: inboxName,
+      contactFirstName: tpl.firstName,
+      contactLastName: tpl.lastName,
+      phone: tpl.phone,
+      address: tpl.address,
+      siret: tpl.siret,
+      notes: null,
+    },
+    { client: input.trx }
+  )
+}
+
+export type InvoiceStatus = Invoice['status']
+
+export type InvoiceFactoryInput = {
+  organizationId: string
+  clientId: string
+  planId: string | null
+  /** Status cible — drive aussi les dates (pending = future, paid = passé). */
+  status: InvoiceStatus
+  /** Numéro override, sinon F-YYYY-XXXX random. */
+  numero?: string
+  /** Montant en centimes. Sinon random 250€-8000€. */
+  amountTtcCents?: number
+  /** Décalage en jours par rapport à aujourd'hui pour issueDate.
+   *  Négatif = passé. */
+  issueOffsetDays?: number
+  /** Délai de paiement en jours (par défaut 30, conforme LME). */
+  paymentTermDays?: number
+  trx?: TransactionClientContract
+}
+
+export async function makeInvoice(input: InvoiceFactoryInput): Promise<Invoice> {
+  const issueOffset = input.issueOffsetDays ?? -randomInt(7, 90)
+  const paymentTerm = input.paymentTermDays ?? 30
+  const issueDate = DateTime.utc().plus({ days: issueOffset }).startOf('day')
+  const dueDate = issueDate.plus({ days: paymentTerm })
+  const amount = input.amountTtcCents ?? randomInt(25_000, 800_000)
+  const numero =
+    input.numero ?? `F-${issueDate.year}-${String(randomInt(1, 9999)).padStart(4, '0')}`
+
+  // paidAt : pour les statuts paid, on simule un paiement après l'échéance
+  // (parfois en avance, parfois en retard — réaliste).
+  let paidAt: DateTime | null = null
+  if (input.status === 'paid') {
+    const paidOffset = randomInt(-5, 25) // -5 = payé en avance, +25 = en retard
+    paidAt = dueDate.plus({ days: paidOffset })
+  }
+
+  // rubisEarned : 1 par relance envoyée + 1 si payée
+  let rubisEarned = 0
+  if (input.status === 'in_relance' || input.status === 'awaiting_user_confirmation') {
+    rubisEarned = randomInt(1, 3)
+  } else if (input.status === 'paid') {
+    rubisEarned = randomInt(0, 4) // certaines payées sans relance
+  }
+
+  return Invoice.create(
+    {
+      organizationId: input.organizationId,
+      clientId: input.clientId,
+      planId: input.planId,
+      numero,
+      amountTtcCents: amount,
+      issueDate,
+      dueDate,
+      paidAt,
+      status: input.status,
+      pdfStorageKey: null,
+      rubisEarned,
+      notes: pickRandom(INVOICE_NOTES_POOL),
+    },
+    { client: input.trx }
+  )
+}
+
+export type ActivityFactoryInput = {
+  organizationId: string
+  invoice: Invoice
+  client: Client
+  trx?: TransactionClientContract
+}
+
+/**
+ * Pour chaque facture, génère les events réalistes :
+ *  - invoice_imported (toujours, à issueDate)
+ *  - relance_sent N fois si status in_relance/awaiting (entre issueDate et now)
+ *  - invoice_paid si status paid
+ */
+export async function makeActivityForInvoice(
+  input: ActivityFactoryInput
+): Promise<void> {
+  const { invoice, client, trx } = input
+
+  // Import — toujours
+  await ActivityEvent.create(
+    {
+      organizationId: input.organizationId,
+      kind: 'invoice_imported',
+      at: invoice.issueDate,
+      label: `Facture <b>${invoice.numero}</b> importée`,
+      meta: { invoiceId: invoice.id, clientId: client.id },
+    },
+    { client: trx }
+  )
+
+  if (invoice.status === 'in_relance' || invoice.status === 'awaiting_user_confirmation') {
+    const relanceCount = randomInt(1, 3)
+    for (let i = 0; i < relanceCount; i++) {
+      const sentAt = invoice.dueDate.plus({ days: 3 + i * 7 })
+      if (sentAt > DateTime.utc()) break
+      await ActivityEvent.create(
+        {
+          organizationId: input.organizationId,
+          kind: 'relance_sent',
+          at: sentAt,
+          label: `Relance J+${3 + i * 7} envoyée à <b>${client.name}</b>`,
+          meta: {
+            invoiceId: invoice.id,
+            clientId: client.id,
+            planStepOrder: i,
+          },
+        },
+        { client: trx }
+      )
+    }
+  }
+
+  if (invoice.status === 'paid' && invoice.paidAt) {
+    await ActivityEvent.create(
+      {
+        organizationId: input.organizationId,
+        kind: 'invoice_paid',
+        at: invoice.paidAt,
+        label: `<b>${client.name}</b> a réglé ${invoice.numero}`,
+        meta: { invoiceId: invoice.id, clientId: client.id },
+      },
+      { client: trx }
+    )
+  }
+}
+
+// ---------------------------------------------------------------------------
+// Recettes — combine les factories pour produire une org démo cohérente
+// ---------------------------------------------------------------------------
+
+export type DemoSeedConfig = {
+  organizationId: string
+  /** Plans déjà provisionnés dans l'org (pour piocher des planId). */
+  plans: Plan[]
+  trx: TransactionClientContract
+  /** Combien de clients (1..N templates dispo). Défaut 8. */
+  clientCount?: number
+}
+
+export type DemoSeedResult = {
+  clients: Client[]
+  invoices: Invoice[]
+  rubisEarned: number
+}
+
+/**
+ * Mix de statuts représentatif d'une TPE active :
+ *  - 5 paid (DSO calc + encaissé total)
+ *  - 4 in_relance (à voir dans le funnel "en relance")
+ *  - 2 awaiting_user_confirmation (check-in en attente)
+ *  - 3 pending (récentes, pas encore relancées)
+ *  - 1 litigation (cas tendu)
+ */
+const INVOICE_RECIPE: Array<{ status: InvoiceStatus; issueOffsetDays: number; planIdx?: number }> = [
+  // Paid — réparties sur 6 mois pour faire vivre le DSO
+  { status: 'paid', issueOffsetDays: -180 },
+  { status: 'paid', issueOffsetDays: -135 },
+  { status: 'paid', issueOffsetDays: -95 },
+  { status: 'paid', issueOffsetDays: -65 },
+  { status: 'paid', issueOffsetDays: -40 },
+  // En relance — échéances passées récentes
+  { status: 'in_relance', issueOffsetDays: -55 },
+  { status: 'in_relance', issueOffsetDays: -50 },
+  { status: 'in_relance', issueOffsetDays: -42 },
+  { status: 'in_relance', issueOffsetDays: -38 },
+  // Awaiting check-in — échéance toute fraîche
+  { status: 'awaiting_user_confirmation', issueOffsetDays: -32 },
+  { status: 'awaiting_user_confirmation', issueOffsetDays: -30 },
+  // Pending — récentes, pas encore arrivées à échéance
+  { status: 'pending', issueOffsetDays: -10 },
+  { status: 'pending', issueOffsetDays: -5 },
+  { status: 'pending', issueOffsetDays: -2 },
+  // Litigation — ancienne, contestée
+  { status: 'litigation', issueOffsetDays: -90 },
+]
+
+export async function seedDemoOrg(config: DemoSeedConfig): Promise<DemoSeedResult> {
+  const { organizationId, plans, trx } = config
+  const clientCount = Math.min(config.clientCount ?? 8, CLIENT_TEMPLATES.length)
+
+  // Crée les clients
+  const clients: Client[] = []
+  for (let i = 0; i < clientCount; i++) {
+    clients.push(await makeClient({ organizationId, index: i, trx }))
+  }
+
+  // Crée les factures (round-robin sur les clients + plans)
+  const invoices: Invoice[] = []
+  for (const [i, recipe] of INVOICE_RECIPE.entries()) {
+    const client = clients[i % clients.length]!
+    const plan = plans[i % plans.length] ?? null
+    const invoice = await makeInvoice({
+      organizationId,
+      clientId: client.id,
+      planId: plan?.id ?? null,
+      status: recipe.status,
+      issueOffsetDays: recipe.issueOffsetDays,
+      trx,
+    })
+    invoices.push(invoice)
+    await makeActivityForInvoice({
+      organizationId,
+      invoice,
+      client,
+      trx,
+    })
+  }
+
+  const rubisEarned = invoices.reduce((s, inv) => s + inv.rubisEarned, 0)
+  return { clients, invoices, rubisEarned }
+}
+
+// ---------------------------------------------------------------------------
+// Helpers
+// ---------------------------------------------------------------------------
+
+function randomInt(min: number, max: number): number {
+  return Math.floor(Math.random() * (max - min + 1)) + min
+}
+
+function pickRandom<T>(arr: readonly T[]): T {
+  return arr[Math.floor(Math.random() * arr.length)]!
+}
+
+// Marque l'export de randomUUID utilisée si on en a besoin ailleurs.
+export { randomUUID }