# Memento Note — Préparation Déploiement SaaS

> **Version:** 1.0 | **Date:** 2026-05-14 | **Statut:** Draft
> **Auteur:** Mary (Business Analyst)

---

## 1. Vision & Proposition de Valeur

### 1.1 Vision Produit

**Memento Note** est une application de prise de notes intelligente alimentée par l'IA, offrant recherche sémantique, suggestions automatiques, et organisation cognitive. L'objectif SaaS est de démocratiser l'accès à une mémoire numérique augmentée par IA — du particulier autodidacte au département R&D enterprise.

### 1.2 Proposition de Valeur par Tier

| Tier | Prix | Positionnement | Proposition Unique |
|------|------|----------------|-------------------|
| **Basic** | Gratuit | Particuliers, étudiants | "Ma première mémoire numérique" — Capturer sans friction, rechercher sans IA |
| **Pro** | 9,90 €/mois | Professionnels, créateurs | "Pensée amplifiée par l'IA" — Accès complet à l'IA avec limites raisonables |
| **Business** | 29,90 €/mois | Équipes, entreprises | "Mémoire organisationnelle partagée" — Collaboration, analytics, limites élevées |

### 1.3 Promotional Hook (PRFAQ style)
> **If I had a penny for every note I lost track of...**
>
> Every knowledge worker knows the frustration: the brilliant idea you jotted down at 11pm, the client insight buried in a 3-year-old doc, the connection between two notes you'd never think to link.
>
> Memento Note doesn't just store your notes. It understands them. It surfaces connections you didn't know existed. It remembers what you forgot.
>
> **Starting at free.**

---

## 2. Modélisation des Tiers d'Abonnement

### 2.1 Tableau Comparatif des Features

| Feature | Basic (Gratuit) | Pro (9,90 €/mois) | Business (29,90 €/mois) |
|---------|:--------------:|:----------------:|:----------------------:|
| **Notes** | 100 max | Illimitées | Illimitées |
| **Notebooks** | 3 | Illimités | Illimités |
| **Collaborateurs** | 0 | 0 | 10 included |
| **AI — Titres auto** | ❌ | ✅ | ✅ |
| **AI — Tags auto** | ❌ | ✅ | ✅ |
| **AI — Recherche sémantique** | ❌ | ✅ (100 req/mois) | ✅ (1000 req/mois) |
| **AI — Reformulation** | ❌ | ✅ (50 req/mois) | ✅ (500 req/mois) |
| **AI — Résumé notebook** | ❌ | ❌ | ✅ |
| **AI — Echo Memory** | ❌ | ❌ | ✅ |
| **AI — Agents web scraper** | ❌ | ❌ | ✅ |
| **Brainstorm collaboratif** | ❌ | ✅ | ✅ |
| **API Access** | ❌ | ❌ | ✅ |
| **Historique & versionning** | 7 jours | 30 jours | Illimité |
| **Export** | PDF | PDF + Markdown | PDF + Markdown + JSON |
| **Canevas Excalidraw** | ✅ | ✅ | ✅ |
| **Support** | Communauté | Email | Priority + SLA 24h |

### 2.2 Quotas IA — Détail

| Service AI | Basic | Pro (mensuel) | Business (mensuel) |
|------------|:-----:|:-------------:|:-----------------:|
| Titre auto | 0 | 200 | 1000 |
| Tags auto | 0 | 200 | 1000 |
| Recherche sémantique | 0 | 100 | 1000 |
| Reformulation texte | 0 | 50 | 500 |
| Résumé notebook | 0 | 0 | 50 |
| Echo Memory | 0 | 0 | 100 |
| Agent Web Scraper | 0 | 0 | 20 runs |
| Chat AI | 0 | 100 | 1000 |
| **Total token estimate** | N/A | ~500K tokens | ~5M tokens |

### 2.3 Période d'Essai

| Tier | Trial |
|------|-------|
| Pro | 14 jours gratuits, sans carte |
| Business | Pas de trial (tier entry élevé) |

---

## 3. Architecture Nécessaire

### 3.1 Vue d'Ensemble des Changements

```
┌─────────────────────────────────────────────────────────────────┐
│                        PRESENTATION LAYER                        │
│  ┌─────────────┐  ┌─────────────┐  ┌─────────────────────────┐  │
│  │  UI Upgrade │  │  Paywall    │  │  Usage Meter / Quota UI  │  │
│  │  Tier Badge │  │  Upgrade    │  │  (Pro: X/200 tags auto)  │  │
│  └─────────────┘  └─────────────┘  └─────────────────────────┘  │
└─────────────────────────────────────────────────────────────────┘
                              │
                              ▼
┌─────────────────────────────────────────────────────────────────┐
│                         API LAYER                                │
│  ┌─────────────┐  ┌─────────────┐  ┌─────────────────────────┐  │
│  │  Billing    │  │  Usage      │  │  Entitlement Check       │  │
│  │  Stripe    │  │  Tracker    │  │  (canUseFeature())       │  │
│  └─────────────┘  └─────────────┘  └─────────────────────────┘  │
│  ┌─────────────┐  ┌─────────────┐  ┌─────────────────────────┐  │
│  │  Subscription│  │  Rate Limit │  │  Analytics Events       │  │
│  │  Webhook    │  │  Per Tier   │  │  (trackFeatureUsage())  │  │
│  └─────────────┘  └─────────────┘  └─────────────────────────┘  │
└─────────────────────────────────────────────────────────────────┘
                              │
                              ▼
┌─────────────────────────────────────────────────────────────────┐
│                         DATA LAYER                              │
│  ┌─────────────┐  ┌─────────────┐  ┌─────────────────────────┐  │
│  │  Subscription│  │  UsageLog   │  │  TenantId / Workspace   │  │
│  │  Model      │  │  (per user) │  │  (future multi-tenancy) │  │
│  └─────────────┘  └─────────────┘  └─────────────────────────┘  │
└─────────────────────────────────────────────────────────────────┘
```

### 3.2 Nouveau Schéma Base de Données (Prisma)

```prisma
// ===== SUBSCRIPTION MODELS =====

enum SubscriptionTier {
  BASIC    // Free
  PRO      // 9,90 €/mois
  BUSINESS // 29,90 €/mois
}

enum SubscriptionStatus {
  ACTIVE
  PAST_DUE
  CANCELED
  TRIALING
  INACTIVE
}

model Subscription {
  id                String   @id @default(cuid())
  userId            String   @unique
  tier              SubscriptionTier @default(BASIC)
  status            SubscriptionStatus @default(ACTIVE)
  
  // Stripe integration
  stripeCustomerId  String?  @unique
  stripeSubscriptionId String? @unique
  stripePriceId     String?
  
  // Trial
  trialEndsAt       DateTime?
  
  // Billing
  currentPeriodStart DateTime
  currentPeriodEnd   DateTime
  
  // Cancellations
  canceledAt         DateTime?
  cancelAtPeriodEnd Boolean @default(false)
  
  createdAt         DateTime @default(now())
  updatedAt         DateTime @updatedAt
  
  user              User @relation(fields: [userId], references: [id], onDelete: Cascade)
}

model UsageLog {
  id            String   @id @default(cuid())
  userId        String
  feature       String   // e.g., "semantic_search", "auto_tag", "chat"
  tokensUsed    Int      @default(0)
  requestsCount Int     @default(1)
  periodStart  DateTime // Monthly reset
  periodEnd    DateTime
  metadata     Json?    // Extra context (noteId, etc.)
  
  createdAt    DateTime @default(now())
  
  user         User @relation(fields: [userId], references: [id], onDelete: Cascade)
  
  @@index([userId, feature, periodStart])
  @@index([userId, periodStart])
}

model FeatureFlag {
  id        String   @id @default(cuid())
  key       String   @unique
  enabled   Boolean  @default(false)
  tiers     SubscriptionTier[] // Which tiers have access
  metadata  Json?    // Rollout percentage, etc.
  
  updatedAt DateTime @updatedAt
}

// ===== ENHANCED USER MODEL =====

model User {
  // ... existing fields ...
  
  // NEW: Subscription
  subscription    Subscription?
  
  // NEW: Workspace (for future multi-tenancy / Business tier collaboration)
  workspaceId     String?
  workspace       Workspace? @relation(fields: [workspaceId], references: [id])
  
  // NEW: Usage tracking
  usageLogs       UsageLog[]
  
  // NEW: Preferred language for AI responses
  aiLanguage      String @default("en")
}

model Workspace {
  id        String   @id @default(cuid())
  name      String
  plan      SubscriptionTier @default(BASIC)
  
  createdAt DateTime @default(now())
  updatedAt DateTime @updatedAt
  
  members   User[]
  // Future: workspace-level settings, analytics, billing
}

// ===== ENHANCED EXISTING MODELS =====

model Note {
  // ... existing fields ...
  
  // NEW: AI usage tracking at note level
  aiTokensUsed Int @default(0)
  lastAiFeature String? // Last AI feature used
}
```

### 3.3 Endpoints API à Ajouter

| Endpoint | Méthode | Purpose | Tier |
|----------|---------|---------|------|
| `/api/billing/create-checkout` | POST | Initier checkout Stripe | Pro+ |
| `/api/billing/portal` | POST | Customer portal Stripe | Pro+ |
| `/api/billing/webhook` | POST | Stripe webhook handler | All |
| `/api/billing/cancel` | POST | Annuler abonnement | Pro+ |
| `/api/billing/upgrade` | POST | Upgrade tier | Basic→Pro |
| `/api/usage/current` | GET | Quotas actuels utilisateur | All |
| `/api/usage/history` | GET | Historique usage | Pro+ |
| `/api/entitlements` | GET | Features accessibles pour tier | All |

### 3.4 Fonctions d'Entitlement Core

```typescript
// lib/entitlements.ts

const TIER_LIMITS = {
  BASIC: {
    maxNotes: 100,
    maxNotebooks: 3,
    collaborators: 0,
    aiRequestsPerMonth: 0, // No AI
    historyDays: 7,
  },
  PRO: {
    maxNotes: Infinity,
    maxNotebooks: Infinity,
    collaborators: 0,
    aiRequestsPerMonth: {
      autoTitle: 200,
      autoTag: 200,
      semanticSearch: 100,
      reformulate: 50,
      chat: 100,
    },
    historyDays: 30,
  },
  BUSINESS: {
    maxNotes: Infinity,
    maxNotebooks: Infinity,
    collaborators: 10,
    aiRequestsPerMonth: {
      autoTitle: 1000,
      autoTag: 1000,
      semanticSearch: 1000,
      reformulate: 500,
      notebookSummary: 50,
      memoryEcho: 100,
      webScraperAgent: 20,
      chat: 1000,
    },
    historyDays: Infinity,
  },
} as const;

export function canUseFeature(userId: string, feature: string): Promise<boolean> {
  // 1. Check subscription tier
  // 2. Check usage within limits
  // 3. Return boolean
}

export async function trackFeatureUsage(
  userId: string, 
  feature: string, 
  tokensUsed: number,
  metadata?: Record<string, any>
): Promise<void> {
  // Increment UsageLog for current period
}

export async function getRemainingQuota(
  userId: string, 
  feature: string
): Promise<{ remaining: number; total: number; resetsAt: Date }> {
  // Return remaining quota for feature
}
```

---

## 4. Modèle de Monétisation

### 4.1 Stripe Integration

```
Pricing Table Stripe Products:
├── Memento Basic (Free)          → No Stripe, free tier
├── Memento Pro (9,90 €/mois)      → Stripe Price: monthly + annual
├── Memento Business (29,90 €/mois) → Stripe Price: monthly + annual
└── Add-ons (future):
    ├── +5 Collaborators           → Seat-based
    └── +AI Pack (extra tokens)   → Usage-based
```

### 4.2 Stratégie de Conversion

```
Funnel de Conversion:
                          
  [Basic Free] ──────────────────────────────────────────► [Churn)
                    │
                    │ 14-day trial offer
                    │ in-app prompt
                    ▼
            [Upgrade to Pro]
                    │
                    │ Team needs
                    │ Advanced features
                    ▼
            [Upgrade to Business]
```

**Touchpoints de Conversion:**
1. **Inline upgrade prompt** — Quand utilisateur hit AI limit (Basic tries AI)
2. **Usage meter in UI** — Barres de progression quota (Pro/Business)
3. **Upgrade modal** — Au clic sur feature payante depuis Basic
4. **Trial banner** — Pour Basic users, "Essayez Pro 14 jours"

### 4.3 Rétention & Engagement

| Tactique | Description |
|----------|-------------|
| Onboarding optimisé | 3-step wizard: Capture → Search → AI Discover |
| Usage-based email | "Vous avez utilisé X feature Y fois ce mois" |
|milestone celebrate | "100 notes créées! Débloquez Pro pour l'IA" |
| Health dashboard | "Votre score mémoire: 87/100" |

---

## 5. Métriques & Analytics pour SaaS

### 5.1 Métriques à Implémenter

#### A. Product Analytics (qui ne coûte pas cher)

| Métrique | Description | Outil |
|---------|-------------|-------|
| DAU/WAU/MAU | Active users daily/weekly/monthly | DB query |
| Feature Adoption | % users using each AI feature | UsageLog |
| Activation Rate | % new users who create 1st note | events |
| Retention Curve | Week 1, 2, 4, 8 retention | events |
| Conversion Rate | Free → Pro → Business | Subscription |

#### B. Usage Metrics (par tier)

```typescript
// Types pour analytics
interface SaaSMetrics {
  // Growth
  newUsersToday: number;
  newUsersThisMonth: number;
  churnedUsersThisMonth: number;
  
  // Revenue
  mrr: number; // Monthly Recurring Revenue
  arr: number; // Annual Run Rate
  arpu: number; // Average Revenue Per User
  
  // Usage
  totalAiRequests: number;
  avgAiRequestsPerUser: number;
  topFeatures: { feature: string; count: number }[];
  
  // Engagement
  medianNotesPerUser: number;
  medianNotebooksPerUser: number;
  activeUsersLast30Days: number;
}
```

#### C. Health Dashboard (Admin)

```
┌─────────────────────────────────────────────────────────┐
│                    SaaS Health                          │
├──────────────┬──────────────┬──────────────┬────────────┤
│  Total Users │   Pro Users  │ Business     │  Churn %   │
│    1,247    │     89       │    12        │   2.3%     │
├──────────────┴──────────────┴──────────────┴────────────┤
│  MRR: 1,040 €        ARR: 12,480 €       ARPU: 9,74 € │
├───────────────────────────────────────────────────────-─┤
│  Feature Adoption (last 30 days)                        │
│  ┌──────────────────────────────────────────────────┐ │
│  │ Auto-Tag    ████████████████████░░░░░  78%        │ │
│  │ Semantic    ████████████████░░░░░░░░░  62%        │ │
│  │ Reformulate ████████████░░░░░░░░░░░░░  44%        │ │
│  │ Chat        ████████░░░░░░░░░░░░░░░░░░  31%        │ │
│  └──────────────────────────────────────────────────┘ │
└─────────────────────────────────────────────────────────┘
```

### 5.2 Tracking Événements

```typescript
// lib/analytics/track.ts

type EventName = 
  | 'note_created'
  | 'note_edited'
  | 'ai_feature_used'
  | 'ai_feature_limit_hit'
  | 'upgrade_intent'
  | 'upgrade_completed'
  | 'downgrade_completed'
  | 'subscription_canceled'
  | 'trial_started'
  | 'trial_converted'
  | 'export_triggered'
  | 'brainstorm_created';

interface TrackPayload {
  userId: string;
  tier: SubscriptionTier;
  timestamp: Date;
  metadata?: Record<string, any>;
}

// Usage:
// track('ai_feature_used', { feature: 'auto_tag', tokensUsed: 150 })
```

---

## 6. Checklist de Déploiement

### Phase 1: Fondations (Week 1-2)

- [ ] Ajouter `Subscription` model to Prisma schema
- [ ] Ajouter `UsageLog` model to Prisma schema
- [ ] Ajouter `FeatureFlag` model to Prisma schema
- [ ] Créer `lib/entitlements.ts` — core entitlement logic
- [ ] Créer `lib/usage-tracker.ts` — track AI feature usage
- [ ] Créer migration Prisma
- [ ] Ajouter `SubscriptionTier` field to User model
- [ ] Mettre à jour `auth.ts` pour exposer le tier dans la session

### Phase 2: API Billing (Week 2-3)

- [ ] Intégrer Stripe SDK
- [ ] Créer `/api/billing/create-checkout` endpoint
- [ ] Créer `/api/billing/portal` endpoint
- [ ] Créer `/api/billing/webhook` handler (subscription events)
- [ ] Tester Stripe webhook en local (stripe-cli)
- [ ] Configurer produits/tarifs dans Stripe Dashboard

### Phase 3: UI Paywall & Quotas (Week 3-4)

- [ ] Créer `<PaywallModal>` component
- [ ] Créer `<UsageMeter>` component (progress bars)
- [ ] Intégrer PaywallModal dans AI feature calls
- [ ] Afficher remaining quotas dans sidebar/header
- [ ] Ajouter "Upgrade" CTA sur les features Basic
- [ ] Créer page `/settings/billing` (manage subscription)

### Phase 4: Analytics & Metrics (Week 4-5)

- [ ] Créer `lib/analytics/track.ts` event tracking
- [ ] Ajouter analytics calls dans les actions clés
- [ ] Construire `<AdminDashboard>` avec vrais metrics
- [ ] Créer `<UserAnalytics>` pour users (self-service)
- [ ] Implémenter DAU/WAU/MAU queries
- [ ] Dashboard churn tracking

### Phase 5: Trial & Conversion (Week 5-6)

- [ ] Implémenter trial flow (14 jours Pro)
- [ ] Email trial reminder (day 7, day 12)
- [ ] Trial-to-paid conversion tracking
- [ ] Optimiser upgrade flow (reduce friction)
- [ ] A/B test upgrade prompts

### Phase 6: Multi-tenancy Preparation (Week 6-8)

- [ ] Ajouter `Workspace` model
- [ ] Créer workspace settings UI
- [ ] Implémenter invite/collaboration pour Business
- [ ] Workspace-level analytics
- [ ] SSO/OAuth pour Business (future)

---

## 7. Risques & Mitigations

| Risque | Probabilité | Impact | Mitigation |
|--------|------------|--------|------------|
| Stripe webhook failures | Moyenne | Élevé | Retry queue + email alerts |
| AI provider costs explode | Haute | Élevé | Hard limits per tier + alerts |
| Users sharing accounts | Moyenne | Moyen | Device tracking + limit concurrent sessions |
| Churn élevé sur trial | Haute | Moyen | Better onboarding + email sequence |
| Complexity explosion | Haute | Moyen | Phased rollout, v1.0 = scope minimal |

---

## 8. Estimation d'Effort

| Phase | Complexity | Risk | Est. Time |
|-------|------------|------|-----------|
| Phase 1: Fondations | ⭐⭐ | 🟡 | 2-3 days |
| Phase 2: Stripe | ⭐⭐⭐ | 🟡 | 2-3 days |
| Phase 3: UI Paywall | ⭐⭐⭐ | 🟢 | 3-4 days |
| Phase 4: Analytics | ⭐⭐⭐ | 🟡 | 2-3 days |
| Phase 5: Trial | ⭐⭐ | 🟢 | 2 days |
| Phase 6: Multi-tenancy | ⭐⭐⭐⭐ | 🔴 | 1-2 weeks |

**Total estimate: 3-4 weeks full-time developer**

---

## Annexes

### A. Fichiers à Modifier

```
Modified Files:
├── prisma/schema.prisma                    # Add Subscription, UsageLog, Workspace
├── lib/entitlements.ts                     # NEW — entitlement logic
├── lib/usage-tracker.ts                    # NEW — usage tracking
├── lib/analytics/track.ts                  # NEW — event tracking
├── lib/stripe.ts                           # NEW — Stripe client
├── app/api/billing/                        # NEW — billing endpoints
├── app/api/usage/current/route.ts           # NEW
├── app/api/entitlements/route.ts           # NEW
├── app/api/webhook/stripe/route.ts         # NEW
├── auth.ts                                 # Expose subscription tier in session
├── middleware.ts                           # Add tier-based route protection
├── components/paywall-modal.tsx            # NEW
├── components/usage-meter.tsx              # NEW
├── components/admin-dashboard.tsx           # Upgrade for real metrics
├── app/(admin)/admin/page.tsx              # Real metrics integration
└── app/(settings)/billing/page.tsx         # NEW — billing management
```

### B. Variables d'Environnement Requises

```env
# Stripe
STRIPE_SECRET_KEY=sk_live_...
STRIPE_WEBHOOK_SECRET=whsec_...
STRIPE_PRICE_PRO_MONTHLY=price_...     # €9.90/mois
STRIPE_PRICE_PRO_ANNUAL=price_...      # ~€99/an (2 mois gratuits)
STRIPE_PRICE_BUSINESS_MONTHLY=price_... # €29.90/mois
STRIPE_PRICE_BUSINESS_ANNUAL=price_...  # ~€299/an (2 mois gratuits)
STRIPE_PRICE_ENTERPRISE=price_...      # Custom seat-based

# Dual-currency: les prix USD sont définis dans Stripe Dashboard
# et affichés selon la locale de l'utilisateur
NEXT_PUBLIC_DEFAULT_CURRENCY=EUR
NEXT_PUBLIC_SUPPORTED_CURRENCIES=EUR,USD

# Feature flags
NEXT_PUBLIC_FEATURE_TRIAL_ENABLED=true
NEXT_PUBLIC_FEATURE_BILLING_ENABLED=true
```

### D. Addons & Enterprise Tier

#### Addon: Collaborateurs Supplémentaires (Business+)

| Addon | Prix |
|-------|------|
| +5 collaborateurs | +4,90 €/mois |
| +10 collaborateurs | +8,90 €/mois |

*Les collaborateurs additionnels sont des "member seats" — ils ont leur propre compte Memento mais appartiennent au même workspace Business.*

#### Enterprise Tier — Proposition

Pour les équipes de **20+ utilisateurs** avec besoins avancés.

| Élément | Détail |
|---------|--------|
| **Prix** | 49,90 €/mois fixes + 3,90 €/utilisateur/mois |
| **Exemple** | 20 users = 49,90 + (20 × 3,90) = 127,90 €/mois |
| **Minimum** | 20 users minimum facturés |
| **Maximum** | Soft cap 500 users, au-delà = pricing custom |

| Feature Enterprise | Détail |
|-------------------|--------|
| **Tout Business** | Inclus |
| **SSO/SAML** | Okta, Azure AD, Google Workspace |
| **Audit Logs** | Accès complet aux logs d'activité équipe |
| **API illimitée** | Rate limit +10x Business |
| **SLA** | 99.9% uptime + support dédié |
| **Onboarding** | Session onboarding live incluse |
| **Custom contracts** | Invoice net-30, BPA available |
| **White-label** | Logo + couleurs custom (future) |
| **Data residency** | EU-only data storage |

**Migration path:** Business → Enterprise est seamless (ajustement facturation, pas de migration data).

---

### E. Tableau Comparatif Complet (4 Tiers)

| Feature | Basic | Pro | Business | Enterprise |
|---------|------:|----:|-----------|-----------:|
| **Prix** | Gratuit | 9,90 €/mois | 29,90 €/mois | 49,90 + 3,90 €/user |
| **Notes** | 100 max | Illimitées | Illimitées | Illimitées |
| **Notebooks** | 3 | Illimités | Illimités | Illimités |
| **Collaborateurs** | 0 | 0 | 10 | 20+ |
| **AI Titres auto** | ❌ | 200/mois | 1000/mois | 5000/mois |
| **AI Tags auto** | ❌ | 200/mois | 1000/mois | 5000/mois |
| **Recherche sémantique** | ❌ | 100/mois | 1000/mois | Illimitée |
| **Reformulation** | ❌ | 50/mois | 500/mois | 2000/mois |
| **Résumé notebook** | ❌ | ❌ | 50/mois | 200/mois |
| **Echo Memory** | ❌ | ❌ | 100/mois | Illimité |
| **Agent Web Scraper** | ❌ | ❌ | 20 runs | 100 runs |
| **Chat AI** | ❌ | 100/mois | 1000/mois | Illimité |
| **Brainstorm collaboratif** | ❌ | ✅ | ✅ | ✅ |
| **API Access** | ❌ | ❌ | ✅ | ✅ (illimitée) |
| **Historique** | 7 jours | 30 jours | Illimité | Illimité |
| **Export formats** | PDF | PDF+MD | PDF+MD+JSON | Tous + API |
| **Support** | Commu | Email | Priority 24h | Dédié + SLA |
| **SSO** | ❌ | ❌ | ❌ | ✅ |
| **Audit Logs** | ❌ | ❌ | ❌ | ✅ |
| **SLA** | ❌ | ❌ | ❌ | 99.9% |

---

## 9. V3 — Zéro Coût Additionnel (Staff Engineer Review)

> **Relecture par Mary (Staff Engineer / Product Growth)** | _Optimisations PLG + B2B — Version Gratuite_
>
> **Changements:** Redis self-hosted (pas Upstash) | Umami auto-hébergé (pas PostHog) | Option PostgreSQL UPSERT pour les quotas

---

### A. Nouvelle Stratégie Freemium — "AI Discovery Pack"

**Problème V1:** Basic avec 0 IA = pas d'effet "Aha!". L'utilisateur ne peut jamais tester la magie du produit.

**Solution V2:** "Starter Pack" — un quota de découverte à vie pour initier les utilisateurs à la valeur IA sans les forcer à payer.

| Feature | Basic Starter | Pro | Business | Enterprise |
|---------|:-------------:|----:|-----------|-----------:|
| **Prix** | Gratuit | 9,90 €/mois | 29,90 €/mois | 49,90 + 3,90 €/user |
| **Notes** | 100 max | Illimitées | Illimitées | Illimitées |
| **Notebooks** | 3 | Illimités | Illimités | Illimités |
| **Collaborateurs** | 0 | 0 | 10 | 20+ |
| **AI Starter Pack** | **✅** | ✅ | ✅ | ✅ |
| — Recherche sémantique | **30 req/mois (lifetime)** | 100/mois | 1000/mois | Illimitée |
| — Tags auto | **20 req/mois (lifetime)** | 200/mois | 1000/mois | 5000/mois |
| — Titres auto | **10 req/mois (lifetime)** | 200/mois | 1000/mois | 5000/mois |
| **AI Reformulation** | ❌ | 50/mois | 500/mois | 2000/mois |
| **AI Résumé notebook** | ❌ | ❌ | 50/mois | 200/mois |
| **AI Echo Memory** | ❌ | ❌ | 100/mois | Illimité |
| **AI Chat** | ❌ | 100/mois | 1000/mois | Illimité |
| **Brainstorm collaboratif** | ❌ | ✅ | ✅ | ✅ |
| **API Access** | ❌ | ❌ | ✅ | ✅ (illimitée) |
| **Historique** | 7 jours | 30 jours | Illimité | Illimité |
| **Support** | Commu | Email | Priority 24h | Dédié + SLA |
| **SSO** | ❌ | ❌ | ❌ | ✅ |
| **Audit Logs** | ❌ | ❌ | ❌ | ✅ |
| **SLA** | ❌ | ❌ | ❌ | 99.9% |

**Pourquoi ce changement:**
- 30 requêtes sémantiques = ~1 semaine d'usage intensif ou 1 mois modéré — assez pour comprendre la valeur
- L'effet "Aha!" arrive typiquement à la 3ème-5ème recherche sémantique (quand tu retrouves un vieux note enfoui)
- Le "lifetime" supprime l'anxiété du quota mensuel — "je garde mes crédits même si je ne souscris pas"

**Copy pour l'onboarding:**
> "Vous avez accès à 30 recherches sémantiques gratuites — à vie. Découvrez comment l'IA retrouve vos idées enfouies."

**Conversion trigger:** Une fois le Starter Pack épuisé, l'utilisateur a **vu la valeur** et comprend ce qu'il perd. Le paywall devient une évidence, pas une frustration.

---

### B. Architecture Quotas Haute Performance — Redis + PostgreSQL Hybride

**Problème V1:** Écrire dans `UsageLog` à chaque requête IA = écriture DB intensive. À 10 000 utilisateurs actifs × 100 req/jour = 1M writes/jour sur PostgreSQL. Ça fond le serveur en pic.

#### B.1 Vue d'Ensemble de l'Architecture

```
┌─────────────────────────────────────────────────────────────────────┐
│                        AI Request Flow                             │
│                                                                     │
│  User → Next.js API → canUseFeature() [Redis counter check]        │
│                        │                                              │
│                        ├── [quota OK] → AI Service → trackUsage()    │
│                        │                                    │         │
│                        │                            Redis INCRBY       │
│                        │                            (async, fire-and- │
│                        │                             forget)          │
│                        │                                              │
│                        └── [quota EXCEEDED] → 429 + PaywallModal    │
│                                                                     │
│  ─── CRON toutes les 5 min ───────────────────────────────────────  │
│  │                                                                  │
│  │  SyncWorker: Lis les compteurs Redis                             │
│  │  → Écrit les增量 (delta) dans PostgreSQL UsageLog               │
│  │  → Réinitialise les compteurs Redis si nouveau mois             │
│  │                                                                  │
│  ─────────────────────────────────────────────────────────────────  │
└─────────────────────────────────────────────────────────────────────┘
```

#### B.2 Redis Schema (Self-Hosted)

```typescript
// Clés Redis par user et par feature
// Format: usage:{userId}:{feature}:{YYYY-MM}
// Option: PostgreSQL UPSERT (plus simple, $0, voir Section B.3)

// Exemples:
// usage:user123:semantic_search:2026-05     → Counter (INCRBY)
// usage:user123:auto_tag:2026-05            → Counter (INCRBY)
// usage:user123:auto_title:2026-05         → Counter (INCRBY)

// Workspace-level pour Business:
// workspace:{workspaceId}:semantic_search:2026-05 → Counter

// TTL: 90 jours (auto-cleanup, covers grace period)
```

#### B.3 Service d'Entitlement Hybride

```typescript
// lib/entitlements.ts

import { Redis } from '@upstash/redis';

// Redis client (côté server, pas Next.js route)
const redis = new Redis({
  url: process.env.UPSTASH_REDIS_REST_URL!,
  token: process.env.UPSTASH_REDIS_REST_TOKEN!,
});

const TIER_LIMITS = {
  BASIC: {
    maxNotes: 100,
    maxNotebooks: 3,
    collaborators: 0,
    aiStarterPack: { semanticSearch: 30, autoTag: 20, autoTitle: 10 },
    historyDays: 7,
  },
  PRO: {
    maxNotes: Infinity,
    maxNotebooks: Infinity,
    collaborators: 0,
    aiRequestsPerMonth: { autoTitle: 200, autoTag: 200, semanticSearch: 100, reformulate: 50, chat: 100 },
    historyDays: 30,
  },
  BUSINESS: {
    maxNotes: Infinity,
    maxNotebooks: Infinity,
    collaborators: 10,
    aiRequestsPerMonth: { autoTitle: 1000, autoTag: 1000, semanticSearch: 1000, reformulate: 500, notebookSummary: 50, memoryEcho: 100, webScraperAgent: 20, chat: 1000 },
    historyDays: Infinity,
  },
  ENTERPRISE: {
    maxNotes: Infinity,
    maxNotebooks: Infinity,
    collaborators: Infinity,
    aiRequestsPerMonth: { autoTitle: 5000, autoTag: 5000, semanticSearch: Infinity, reformulate: 2000, notebookSummary: 200, memoryEcho: Infinity, webScraperAgent: 100, chat: Infinity },
    historyDays: Infinity,
  },
} as const;

// READ: fast path — Redis only
export async function canUseFeature(userId: string, feature: string): Promise<{ allowed: boolean; remaining: number; limit: number }> {
  const user = await getUserSubscription(userId);
  const tier = user.subscription?.tier ?? 'BASIC';
  const limit = getLimit(tier, feature);
  const key = `usage:${userId}:${feature}:${getCurrentPeriodKey()}`;
  
  const [currentStr, maxStr] = await Promise.all([
    redis.get<string>(key),
    limit === Infinity ? Promise.resolve('Infinity') : Promise.resolve(String(limit)),
  ]);
  
  const current = parseInt(currentStr ?? '0');
  const max = maxStr === 'Infinity' ? Infinity : parseInt(maxStr);
  
  if (max === Infinity) return { allowed: true, remaining: Infinity, limit: Infinity };
  
  return {
    allowed: current < max,
    remaining: Math.max(0, max - current),
    limit: max,
  };
}

// WRITE: fire-and-forget, ne bloque pas la requête IA
export async function trackFeatureUsage(
  userId: string,
  feature: string,
  tokensUsed: number,
  metadata?: Record<string, any>
): Promise<void> {
  const key = `usage:${userId}:${feature}:${getCurrentPeriodKey()}`;
  
  // Piped transaction — atomic increment sans read-modify-write
  redis.pipeline()
    .incrby(key, 1)
    .incrbyfloat(`${key}:tokens`, tokensUsed)
    .expire(key, 90 * 24 * 60 * 60) // 90 days TTL
    .exec();
}

function getCurrentPeriodKey(): string {
  return new Date().toISOString().slice(0, 7); // "2026-05"
}

function getLimit(tier: SubscriptionTier, feature: string): number {
  const tierLimits = TIER_LIMITS[tier];
  if ('aiStarterPack' in tierLimits && feature in tierLimits.aiStarterPack) {
    return tierLimits.aiStarterPack[feature as keyof typeof tierLimits.aiStarterPack];
  }
  if ('aiRequestsPerMonth' in tierLimits && feature in tierLimits.aiRequestsPerMonth) {
    return tierLimits.aiRequestsPerMonth[feature as keyof typeof tierLimits.aiRequestsPerMonth];
  }
  return 0;
}
```

#### B.4 Sync Worker — PostgreSQL

Un CRON job (ou serverless function trigger toutes les 5 min) synchronise les compteurs Redis → PostgreSQL pour facturation et historique.

```typescript
// app/api/cron/sync-usage/route.ts
// Trigger: every 5 minutes via Vercel Cron ou node-cron

export async function POST() {
  const keys = await redis.keys('usage:*:2026-05'); // Tous les compteurs du mois
  
  // Batch processing par 1000 pour éviter de tuer Redis
  for (const key of keys) {
    const [parts, counter, tokens] = await Promise.all([
      key.split(':'), // [usage, userId, feature, period]
      redis.get<number>(key),
      redis.get<number>(`${key}:tokens`),
    ]);
    
    const [, userId, feature, period] = parts;
    
    await prisma.usageLog.upsert({
      where: {
        userId_feature_periodStart: {
          userId,
          feature,
          periodStart: new Date(period + '-01'),
        },
      },
      create: {
        userId,
        feature,
        periodStart: new Date(period + '-01'),
        periodEnd: endOfMonth(new Date(period + '-01')),
        requestsCount: counter ?? 0,
        tokensUsed: tokens ?? 0,
      },
      update: {
        requestsCount: counter ?? 0,
        tokensUsed: tokens ?? 0,
        metadata: { lastSyncedAt: new Date() },
      },
    });
  }
  
  return NextResponse.json({ synced: keys.length });
}
```

#### B.5 Schéma Prisma Updated (V2)

```prisma
// ===== SUBSCRIPTION MODELS =====

enum SubscriptionTier {
  BASIC    // Free with Starter Pack
  PRO      // 9,90 €/mois
  BUSINESS // 29,90 €/mois
  ENTERPRISE // 49,90 + 3,90 €/user
}

enum SubscriptionStatus {
  ACTIVE
  PAST_DUE
  CANCELED
  TRIALING
  INACTIVE
}

enum WorkspaceRole {
  OWNER           // Full control, billing
  ADMIN           // Can manage members, can't delete workspace
  MEMBER          // Can create/edit notes
  VIEWER          // Read-only access
}

model Subscription {
  id                    String   @id @default(cuid())
  userId                String   @unique
  tier                  SubscriptionTier @default(BASIC)
  status                SubscriptionStatus @default(ACTIVE)
  
  stripeCustomerId       String?  @unique
  stripeSubscriptionId   String?  @unique
  stripePriceId         String?
  
  trialEndsAt           DateTime?
  currentPeriodStart    DateTime
  currentPeriodEnd      DateTime
  canceledAt            DateTime?
  cancelAtPeriodEnd     Boolean  @default(false)
  
  createdAt             DateTime @default(now())
  updatedAt             DateTime @updatedAt
  
  user                  User @relation(fields: [userId], references: [id], onDelete: Cascade)
}

// UsageLog devient un journal de sync, pas un counter temps-réel
model UsageLog {
  id             String   @id @default(cuid())
  userId         String
  feature        String   // semantic_search, auto_tag, etc.
  periodStart    DateTime // 1er jour du mois
  periodEnd      DateTime // Dernier jour du mois
  requestsCount  Int      @default(0)
  tokensUsed     Int      @default(0)
  
  // Flag de sync (Redis → PG)
  syncedAt       DateTime?
  
  metadata       Json?
  createdAt     DateTime @default(now())
  
  user           User @relation(fields: [userId], references: [id], onDelete: Cascade)
  
  @@unique([userId, feature, periodStart])
  @@index([userId, periodStart])
  @@index([periodStart])
}

model FeatureFlag {
  id        String   @id @default(cuid())
  key       String   @unique
  enabled   Boolean  @default(false)
  tiers     SubscriptionTier[]
  metadata  Json?
  updatedAt DateTime @updatedAt
}

// ===== WORKSPACE MODEL =====

model Workspace {
  id          String   @id @default(cuid())
  name        String
  plan        SubscriptionTier @default(BASIC)
  slug        String   @unique // URL: app.memento.io/acme
  
  // Workspace-level quotas (Business/Enterprise)
  aiQuotaOverrides Json?    // Override user quotas if workspace-wide
  
  createdAt   DateTime @default(now())
  updatedAt   DateTime @updatedAt
  
  members     WorkspaceMember[]
  invitations WorkspaceInvitation[]
  
  // Pour le billing Enterprise
  seatCount   Int @default(1)
  maxSeats    Int @default(20)
}

model WorkspaceMember {
  id          String   @id @default(cuid())
  userId      String
  workspaceId String
  role        WorkspaceRole @default(MEMBER)
  joinedAt    DateTime @default(now())
  
  user        User     @relation(fields: [userId], references: [id], onDelete: Cascade)
  workspace   Workspace @relation(fields: [workspaceId], references: [id], onDelete: Cascade)
  
  @@unique([userId, workspaceId])
  @@index([workspaceId])
}

model WorkspaceInvitation {
  id          String   @id @default(cuid())
  workspaceId  String
  email       String
  role        WorkspaceRole @default(MEMBER)
  token       String   @unique // Magic link token
  expiresAt   DateTime
  acceptedAt  DateTime?
  
  workspace   Workspace @relation(fields: [workspaceId], references: [id], onDelete: Cascade)
  
  @@unique([workspaceId, email])
}

// ===== USER MODEL UPDATED =====

model User {
  // ... existing 42 relations ...
  
  subscription   Subscription?
  workspaceMembers WorkspaceMember[]
  usageLogs      UsageLog[]
  
  // Nouveaux champs
  aiLanguage     String  @default("en")
  locale         String  @default("en")
  
  // Workspace invitation (si en attente)
  pendingInvitation WorkspaceInvitation?
}

// Note: Workspace field removed from User model (many-to-many via WorkspaceMember)
```

---

### C. Modèle B2B & RBAC

#### C.1Hiérarchie des Permissions

```
Workspace (Organisation)
│
├── OWNER (Propriétaire)
│   ├── Full control
│   ├── Billing management
│   ├── Can delete workspace
│   └── Only one per workspace (the creator)
│
├── ADMIN
│   ├── Manage members (invite, remove, change roles)
│   ├── Manage workspace settings
│   └── Cannot delete workspace or change billing
│
├── MEMBER
│   ├── Create/edit/delete own notes
│   ├── Create/edit/delete own notebooks
│   ├── Use AI features (consomme du workspace quota)
│   └── Participate in brainstorm sessions
│
└── VIEWER
    ├── Read-only access to all notes
    └── Cannot use AI features
```

#### C.2 API Entitlements — Résolution Multi-Niveaux

```typescript
// lib/entitlements.ts

export interface EntitlementContext {
  userId: string;
  workspaceId?: string; // Si dans un workspace B2B
  tier: SubscriptionTier;
  workspaceRole?: WorkspaceRole;
}

export async function canUseFeature(ctx: EntitlementContext, feature: string): Promise<EntitlementResult> {
  // 1. Workspace-level quota check (B2B)
  if (ctx.workspaceId) {
    const workspaceQuota = await getWorkspaceQuota(ctx.workspaceId, feature);
    if (workspaceQuota.exhausted) {
      return {
        allowed: false,
        reason: 'WORKSPACE_QUOTA_EXHAUSTED',
        message: 'Le quota IA de votre équipe est épuisé. Demandez à votre admin.',
        workspaceId: ctx.workspaceId,
      };
    }
    return { allowed: true, remaining: workspaceQuota.remaining };
  }
  
  // 2. User-level quota check (B2C)
  const userQuota = await getUserQuotaFromRedis(ctx.userId, feature);
  if (!userQuota.allowed) {
    return {
      allowed: false,
      reason: 'USER_QUOTA_EXHAUSTED',
      message: `Votre quota ${feature} est épuisé. ${upsellMessage(ctx.tier)}`,
      upgradeTier: ctx.tier === 'BASIC' ? 'PRO' : undefined,
    };
  }
  
  return { allowed: true, remaining: userQuota.remaining };
}

// Exemple de réponse quand workspace quota épuisé
interface EntitlementResult {
  allowed: boolean;
  remaining: number;
  reason?: 'WORKSPACE_QUOTA_EXHAUSTED' | 'USER_QUOTA_EXHAUSTED' | 'TIER_LIMITED';
  message?: string;
  upgradeTier?: 'PRO' | 'BUSINESS'; // Pour afficher le bon CTA
  workspaceId?: string;
}
```

#### C.3 Communication Quota Épuisé aux Membres

```
Scénario: Workspace Business a dépasé son quota de recherche sémantique

1. Admin recoit un email: "Votre quota IA équipe est à 80%"
2. Les membres VIEWER/MEMBER voient un warning banner:
   "Le quota IA de votre équipe sera bientôt épuisé" 
   (pas de bouton upgrade, juste une information)
3. Si le quota est vraiment épuisé:
   - Les appels IA retours 429 avec { reason: "WORKSPACE_QUOTA_EXHAUSTED" }
   - Le banner devient rouge avec CTA "Contacter l'admin"
   - L'admin peut Upgrade le workspace ou acheter des credits additionnels
```

#### C.4 Endpoints API pour Workspaces

| Endpoint | Méthode | Purpose | Rôle Requis |
|---------|---------|---------|-------------|
| `/api/workspaces` | POST | Créer workspace | Any authenticated |
| `/api/workspaces` | GET | Lister mes workspaces | Any authenticated |
| `/api/workspaces/[id]` | GET | Détail workspace | ADMIN+ |
| `/api/workspaces/[id]/members` | GET | Lister membres | ADMIN+ |
| `/api/workspaces/[id]/members/invite` | POST | Inviter membre | ADMIN+ |
| `/api/workspaces/[id]/members/[userId]` | PATCH | Changer rôle | OWNER |
| `/api/workspaces/[id]/members/[userId]` | DELETE | Retirer membre | ADMIN+ |
| `/api/workspaces/[id]/quota` | GET | Quotas workspace | ADMIN+ |
| `/api/workspaces/[id]/invitations/[token]` | POST | Accepter invitation | Any authenticated (email match) |

---

### D. Stack Analytics Découplée — PostHog Integration

**Problème V1:** Requêter DAU/MAU directement sur PostgreSQL = tables verrouillées pendant les heures de pic.

**Solution V2:** PostHog (ou Plausible/Umami pour une alternative moins chère) comme event store central. PostgreSQL ne sert que pour la facturation.

#### D.1Pourquoi PostHog?

| Critère | PostgreSQL Direct | PostHog |
|---------|-----------------|---------|
| Cost at 100K DAU | ~$200/mo (RDS large) | ~$85/mo (PostHog Cloud) |
| Query performance | Dégradé en pic | Constante |
| Session replay | Non | ✅ |
| Feature flags | DIY | ✅ Built-in |
| Funnel analysis | Complex SQL | ✅ 1-click |
| GDPR compliance | Full control | EU cloud available |

#### D.2 Event Payload Structure

```typescript
// lib/analytics/posthog.ts

import { PostHog } from 'posthog-node';

const posthog = new PostHog(process.env.NEXT_PUBLIC_POSTHOG_API_KEY!, {
  host: process.env.NEXT_PUBLIC_POSTHOG_HOST,
  flushAt: 20,      // Batch de 20 events pour réduire les appels
  flushInterval: 10, // ou toutes les 10 secondes
});

// Deux types d'événements: client et server
type EventSource = 'client' | 'server';

interface MementoEvent {
  event: string;
  properties: {
    // Core dimensions (toujours présents)
    userId: string;
    tier: SubscriptionTier;
    workspaceId?: string;
    source: EventSource;
    
    // Feature-specific
    feature?: string;
    noteId?: string;
    notebookId?: string;
    
    // AI-specific
    aiProvider?: string;
    tokensUsed?: number;
    requestDurationMs?: number;
    
    // Billing-specific
    plan?: string;         // 'monthly' | 'annual'
    currency?: string;     // 'EUR' | 'USD'
    amountCents?: number;
    
    // UX-specific
    screenName?: string;
    elementId?: string;
    interactionType?: 'click' | 'focus' | 'submit' | 'scroll';
    
    // Meta
    appVersion: string;
    platform: 'web' | 'ios' | 'android';
  };
  timestamp?: Date;
}

// Événements SERVER (Stripe, billing, usage)
async function trackServerEvent(event: string, properties: Omit<MementoEvent['properties'], 'source'>) {
  await posthog.capture({
    event,
    properties: { ...properties, source: 'server' },
  });
}

// Événements CLIENT (UX, interaction)
async function trackClientEvent(event: string, properties: Omit<MementoEvent['properties'], 'source'>) {
  await posthog.capture({
    event,
    properties: { ...properties, source: 'client' },
  });
}

// ===== Server Events (Stripe & Billing) =====
// Ces événements sont critiques pour la facturation et ne doivent PAS dépendre du client

trackServerEvent('stripe_checkout_started', {
  userId,
  tier: 'PRO',
  plan: 'monthly',
  currency: 'EUR',
  amountCents: 990,
});

trackServerEvent('stripe_subscription_created', {
  userId,
  tier: 'PRO',
  plan: 'annual',
  currency: 'EUR',
  amountCents: 9900,
});

trackServerEvent('stripe_webhook_received', {
  userId,
  eventType: 'invoice.paid',
  // Pas de userId si le webhook est avant authentication
});

trackServerEvent('ai_request_completed', {
  userId,
  tier: 'PRO',
  feature: 'semantic_search',
  aiProvider: 'openai',
  tokensUsed: 1500,
  requestDurationMs: 340,
});

// ===== Client Events (UX) =====
// Ces événements viennent du browser via posthog.capture() automatique

trackClientEvent('page_viewed', {
  userId,
  tier: 'PRO',
  screenName: 'note-editor',
});

trackClientEvent('feature_discovered', {
  userId,
  tier: 'BASIC',
  feature: 'semantic_search',
});

trackClientEvent('upgrade_intent_clicked', {
  userId,
  tier: 'BASIC',
  currentFeature: 'semantic_search',
  screenName: 'search-results',
});

trackClientEvent('starter_pack_exhausted', {
  userId,
  tier: 'BASIC',
  lastFeature: 'semantic_search',
});
```

#### D.3 PostHog Feature Flags (Pour A/B Tests)

```typescript
// lib/analytics/feature-flags.ts

// Gate le pricing display par locale
const showUSD = posthog.isFeatureEnabled('pricing-display-usd', { userId });

// Gate le trial offer
const showTrial = posthog.isFeatureEnabled('trial-offer-14days', { userId });

// Gate le paywall style
const paywallStyle = posthog.isFeatureEnabled('paywall-v2', { userId }) ? 'v2' : 'v1';

// Gate le AI starter pack
const hasStarterPack = posthog.isFeatureEnabled('ai-starter-pack', { userId });
```

#### D.4 Dashboard PostHog — Vues Clés

| Dashboard | Query | Use Case |
|-----------|-------|----------|
| **PLG Funnel** | Signup → Create note → Use AI → Upgrade | Mesure activation |
| **Feature Adoption** | `% users with event 'ai_feature_used' in 7d` | Priorité roadmap |
| **Retention** | Week 1/2/4/8 cohort retention | Réduce churn |
| **Usage by Tier** | Group by properties.tier | Validate pricing |
| **Revenue** | Sum of stripe events, filter by eventType | MRR/ARR |

#### D.5 GDPR & Data Residency

```typescript
// Pour EU-only data
const posthog = new PostHog(process.env.POSTHOG_API_KEY!, {
  host: 'https://eu.i.posthog.com', // EU datacenter
  flushAt: 20,
  flushInterval: 10,
});

// Option: anonymiser les IPs
posthog.capture('page_viewed', {
  properties: {
    // PostHog enregistre $ip si non spécifié — on le met à 0
    '$ip': '0.0.0.0', // Anonymisé
  },
});

// Option:拒绝 session recording sur pages sensibles
// Dans le composant React:
// <PostHogProvider sessionRecording={{ blockBy: '#note-content' }} />
```

---

### E. Résumé des Changements V1 → V3

| Section | V1 | V2 |
|--------|----|----|
| **Freemium** | Basic = 0 IA | Basic = "Starter Pack" (30 req sémantique lifetime) |
| **Architecture quotas** | PostgreSQL direct (1M writes/jour) | Redis (Upstash) + sync CRON PostgreSQL |
| **RBAC** | Simple user.role | Workspace + WorkspaceRole enum (OWNER/ADMIN/MEMBER/VIEWER) |
| **Analytics** | PostgreSQL queries | PostHog (event store) + PostgreSQL (facturation) |
| **Conversion trigger** | Inline upgrade prompt | Starter Pack exhaust trigger (plus fort car valeur prouvée) |
| **B2B quotas** | Per-user only | Workspace-level quotas partages |

---

### F. Fichiers à Modifier / Ajouter (V3)

```
NEW FILES:
├── docker-compose.yml                     # Redis + Umami (VPS)
├── lib/entitlements.ts                    # PostgreSQL UPSERT ou Redis self-hosted
├── lib/redis.ts                           # Redis client (si Option B)
├── lib/analytics/umami.ts                 # Umami tracker
├── app/api/cron/sync-usage/route.ts      # CRON sync (si Redis)
├── app/api/workspaces/                    # Workspace management APIs
├── app/api/billing/webhook/route.ts      # Stripe webhook

UPDATED FILES:
├── prisma/schema.prisma                   # UsageCounter, Workspace, WorkspaceMember, WorkspaceInvitation, WorkspaceRole enum
├── auth.ts                               # Expose tier + workspaceRole in session
├── middleware.ts                          # Workspace slug routing
└── components/paywall-modal.tsx          # Add workspace quota exhausted state
```

---

### G. Fichiers à Modifier / Ajouter (V3)

```
NEW FILES:
├── docker-compose.yml                     # Redis + Umami (VPS)
├── lib/entitlements.ts                    # PostgreSQL UPSERT ou Redis selon choix
├── lib/redis.ts                           # Redis client (si Option B)
├── lib/analytics/umami.ts                 # Umami tracker
├── app/api/cron/sync-usage/route.ts      # CRON sync (si Redis)
├── app/api/workspaces/                    # Workspace management APIs
├── app/api/billing/webhook/route.ts      # Stripe webhook

UPDATED FILES:
├── prisma/schema.prisma                   # UsageCounter, Workspace, WorkspaceMember, WorkspaceInvitation, WorkspaceRole enum
├── auth.ts                               # Expose tier + workspaceRole in session
├── middleware.ts                          # Workspace slug routing
└── components/paywall-modal.tsx          # Add workspace quota exhausted state
```

---

### H. Enterprise Billing — Pourquoi Complexe (et Alternative Simple)

**Pourquoi complexe:**

Stripe Licensing API pour seat-based billing demande:
1. Webhook pour prorata (ajout/retrait de seats en cours de mois)
2. Minimum 20 seats enforced en code
3. Addons +5 seats + Licensing API = double complexité

**Alternative simple pour V1:**

| Approche | Complexité | Pour qui |
|----------|------------|---------|
| **Manuel (dashboard admin)** | $0 | < 10 clients Enterprise |
| **Subscription + quantity** | Faible | Tu changes le quantity manuellement dans Stripe Dashboard |
| **Full Licensing API** | Haute | 10+ clients Enterprise (plus tard) |

**Ma recommandation:** Enterprise = **subscription simple** à $49.90 + $3.90 × seats. Tu gères le seat count manuellement dans `/admin`. Licensing API plus tard si > 10 clients Enterprise.

---

### I. Docker Compose Prêt à Déployer

```yaml
# docker-compose.yml — Déploiement sur VPS (Ubuntu 22.04)

version: '3.8'
services:
  redis:
    image: redis:7-alpine
    container_name: memento-redis
    command: >
      redis-server
      --requirepass ${REDIS_PASSWORD}
      --appendonly yes
      --maxmemory 256mb
      --maxmemory-policy allkeys-lru
    volumes:
      - redis_data:/data
    ports:
      - "127.0.0.1:6379:6379"
    restart: unless-stopped

  umami:
    image: umami-software/umami:postgresql-latest
    container_name: memento-umami
    ports:
      - "127.0.0.1:3001:3000"
    environment:
      DATABASE_URL: postgresql://${PG_USER}:${PG_PASSWORD}@postgres:5432/${PG_DB}?schema=umami
      DATABASE_TYPE: postgresql
      APP_SECRET: ${UMAMI_APP_SECRET}
    volumes:
      - umami_data:/app/data
    restart: unless-stopped

volumes:
  redis_data:
  umami_data:
```

```bash
# Commandes de déploiement
docker-compose up -d
docker-compose ps   # Vérifier que tout tourne
docker-compose logs -f redis  # Logs si besoin
```

---

### J. Résumé — Coût Total $0

| Composant | Option Coût Zero |替代方案 payante |
|-----------|-----------------|-----------------|
| **Analytics** | Umami auto-hébergé | PostHog Cloud ($85/mois) |
| **Cache/Compteurs** | Redis self-hosted ou PostgreSQL UPSERT | Upstash ($10/mois) |
| **Email transactionnel** | Resend (tu l'as) | SendGrid, Postmark |
| **Serveur** | Ton VPS existant | Vercel, Railway |
| **Total additionnel** | **$0** | ~$95/mois |