kalei/docs/technical/kalei-infrastructure-plan.md

# Kalei — Infrastructure & Financial Plan

## The Constraint

**Starting capital:** €0 – €2,000 max
**Monthly burn target:** Under €30/month at launch, scaling only when revenue justifies it
**Goal:** Ship a production-quality AI mental wellness app that can serve its first 1,000 users without going broke

---

## 1. The AI Decision (This Is Everything)

AI is 70–90% of Kalei's variable cost. Every other infrastructure decision is rounding error compared to this one.

### The Research That Changed Everything

A 2025 Nature study tested LLMs on 5 standardized emotional intelligence tests. DeepSeek V3, Claude 3.5 Haiku, and several other LLMs all outperformed humans (81% avg vs 56% human avg). The gap between Claude and cheaper open-weight models on emotion understanding is much smaller than originally assumed. This opened the door to a dramatically cheaper AI strategy.

### The Decision: OpenRouter Gateway + DeepSeek V3.2 (Non-Chinese Hosting)

**Primary engine:** DeepSeek V3.2 via OpenRouter, pinned to non-Chinese providers (DeepInfra / Fireworks)
**Automatic fallback:** Claude Haiku 4.5 via OpenRouter (activated if primary provider has an outage)
**Batch processing:** DeepSeek V3.2 for Spectrum analysis and weekly insights (no separate batch tier needed at this price point)

| | DeepInfra (via OpenRouter) | Claude Haiku 4.5 (fallback) | Savings |
|---|---|---|---|
| Input (cache miss) | $0.26/M | $1.00/M | 74% cheaper |
| Input (cache hit) | $0.216/M | $0.10/M | — |
| Output | $0.38/M | $5.00/M | 92% cheaper |

### Why OpenRouter + Non-Chinese Providers (Not DeepSeek Direct)

DeepSeek's direct API is cheaper ($0.028 cache hits, $0.42 output) but routes all data through Chinese servers. For a mental wellness app handling sensitive emotional content, this is a non-starter — both for user trust and GDPR considerations. Routing through DeepInfra/Fireworks (US/EU infrastructure) via OpenRouter costs ~2–3x more than the direct API but still delivers ~85–90% savings vs Claude Haiku.

OpenRouter gives us:
- **Provider pinning** — deterministic routing to non-Chinese hosts via the `order` array in API calls
- **Automatic failover** — if DeepInfra goes down, routes to Fireworks or Claude Haiku automatically
- **One API, one billing** — no lock-in, switching models is a config change not a code change
- **No markup** on base provider pricing (OpenRouter doesn't add fees on paid models)

### Self-Hosted GPU: Not Yet

GPU self-hosting (Qwen3-30B-A3B on RTX 4090 at ~$245/month) only beats the API route at ~600+ DAU. Below that, APIs are cheaper. Revisit when user base justifies fixed GPU costs, or if data sovereignty becomes a hard requirement.

### Why Not Tiered Models (Option D)?

We evaluated a hybrid strategy using different models per feature tier (DeepSeek for emotional tasks, Qwen3 via Groq for structured generation, batch APIs for analytics). At our current scale, the complexity cost outweighs the savings: separate prompt tuning, multiple quality benchmarks, routing logic in the ai_gateway, and edge cases when tasks don't cleanly fit one tier. The ~$30–50/month savings doesn't justify maintaining four model configurations as a solo founder. Introduce tiering only when usage data reveals which tasks genuinely benefit from a different model.

---

## 2. Per-User AI Cost Model

Here's what a real user session looks like in tokens:

### The Mirror (Freeform Writing + AI Highlights)

| Component | Input Tokens | Output Tokens |
|---|---|---|
| System prompt (cached after first call) | ~800 | — |
| User's writing (per session, ~300 words) | ~400 | — |
| Fragment detection (5 highlights avg) | — | ~500 |
| Inline reframe (per tap, user triggers ~2) | ~200 | ~150 |
| Session Reflection | ~300 | ~400 |
| **Total per Mirror session** | **~1,700** | **~1,050** |

With prompt caching (system prompt cached): effective input ≈ 980 tokens (800 cached at 0.1×) + 900 fresh = **~980 billable input tokens**

### The Kaleidoscope (One Turn)

| Component | Input Tokens | Output Tokens |
|---|---|---|
| System prompt (cached) | ~600 | — |
| User's fragment + context | ~300 | — |
| 3 reframe perspectives | — | ~450 |
| **Total per Turn** | **~900** | **~450** |

With caching: ~360 billable input tokens

### The Lens (Daily Affirmation)

| Component | Input Tokens | Output Tokens |
|---|---|---|
| System prompt (cached) | ~400 | — |
| User context + goals | ~200 | — |
| Generated affirmation | — | ~100 |
| **Total per daily affirmation** | **~600** | **~100** |

With caching: ~240 billable input tokens

### The Guide (Active Coaching Layer)

| Component | Input Tokens | Output Tokens |
|---|---|---|
| System prompt (cached after first call) | ~600 | — |
| Goal Check-In conversation (per check-in, ~4 exchanges) | ~1,200 | ~800 |
| Cross-Feature Bridge detection (per analysis pass) | ~500 | ~200 |
| Attention Prompt generation (per prompt) | ~300 | ~100 |
| Evidence Intervention (per intervention) | ~400 | ~300 |
| Weekly Pulse AI Read (per pulse) | ~800 | ~500 |
| **Total per weekly cycle (1 check-in + 7 prompts + 1 pulse + 1 bridge analysis)** | **~4,600** | **~2,600** |

With prompt caching: effective input ≈ 3,200 billable input tokens per week

**Note on Guide intelligence:** The Guide requires cross-feature context analysis — it reads Mirror sessions, Turn history, and Lens goals to generate bridges and check-ins. This makes its per-call token count higher than single-feature interactions, but the calls are less frequent (weekly check-ins, daily prompts, bridges max once/day). The Guide also benefits heavily from prompt caching since its system prompt and user context window are reused across multiple Guide interactions.

### Monthly Usage Per Active User Profile

**Free user** (3 Turns/day, 2 Mirror sessions/week, daily Lens, basic Guide):

| Feature | Sessions/Month | Billable Input Tokens | Output Tokens |
|---|---|---|---|
| Kaleidoscope | 90 Turns | 32,400 | 40,500 |
| Mirror | 8 sessions | 7,840 | 8,400 |
| Lens | 30 affirmations | 7,200 | 3,000 |
| Guide (basic: 1 check-in, 12 prompts, 4 pulses self-report, bridges) | ~15 interactions | 6,400 | 3,200 |
| **Total** | | **53,840** | **55,100** |

**Cost with DeepSeek V3.2 via DeepInfra:** (53,840 × ~$0.24 blended + 55,100 × $0.38) / 1,000,000 = **$0.013 + $0.021 = ~$0.034/month**
*(Previous Claude Haiku 4.5 estimate: $0.33/month — this is a ~90% reduction)*

**Prism subscriber** (unlimited usage, assume 2× free user + full Guide + Spectrum):

| Feature | Sessions/Month | Billable Input Tokens | Output Tokens |
|---|---|---|---|
| Kaleidoscope | 180 Turns | 64,800 | 81,000 |
| Mirror | 16 sessions | 15,680 | 16,800 |
| Lens | 30 affirmations | 7,200 | 3,000 |
| Guide (full: 4 check-ins, 30 prompts, 4 full pulses, evidence interventions, all bridges) | ~50 interactions | 22,400 | 14,000 |
| Spectrum (batch) | 4 analyses | 8,000 | 12,000 |
| **Total** | | **118,080** | **126,800** |

**Cost with DeepSeek V3.2 via DeepInfra:** (118,080 × ~$0.24 + 126,800 × $0.38) / 1,000,000 = **$0.028 + $0.048 = ~$0.076/month**
*(Previous Claude Haiku 4.5 estimate: $0.72/month — this is a ~89% reduction)*

**Reality check:** Most users won't hit max usage. Expect average active user cost of **$0.03–$0.06/month.** The Guide adds ~$0.005–$0.01/month for free users and ~$0.01–$0.02/month for Prism subscribers — negligible cost for a significant retention benefit.

---

## 3. Infrastructure Stack

### Server: Netcup VPS 1000 G12

| Spec | Value |
|---|---|
| CPU | 4 vCores (AMD EPYC) |
| RAM | 8 GB DDR5 ECC |
| Storage | 256 GB NVMe |
| Bandwidth | Unlimited, 2.5 Gbps |
| Location | Nuremberg, Germany |
| **Price** | **€8.45/month** (~$9.20) |

This runs everything: API server, database, Redis cache, reverse proxy. Comfortably handles hundreds of concurrent users. Can upgrade to VPS 2000 (€15.59/mo) when we outgrow it.

**What runs on this box:**
- Node.js / Express API server (or Fastify for speed)
- PostgreSQL 16 (direct install, not Supabase overhead)
- Redis (session cache, rate limiting, prompt cache keys)
- Nginx (reverse proxy, SSL termination, rate limiting)
- Certbot (free SSL via Let's Encrypt)

### Why NOT Supabase Cloud

Supabase Cloud Pro is $25/month — that's 3× our VPS cost and we'd still need a separate server for the API layer. Self-hosting Supabase via Docker is possible but adds ~2GB RAM overhead for all the services (GoTrue, PostgREST, Realtime, Storage, Kong). On an 8GB VPS, that leaves very little room.

**Instead:** Run PostgreSQL directly. We get all the database functionality we need (Row Level Security, triggers, functions, JSON support) without the Supabase services overhead. We build our own auth layer (JWT-based, simple) and our own API. This is leaner, cheaper, and gives us full control.

If we later want Supabase features (real-time subscriptions, storage), we can self-host just the components we need.

### Domain & DNS

| Item | Cost |
|---|---|
| kalei.ai domain | ~$50–70/year (~$5/month) |
| Cloudflare DNS (free tier) | $0 |
| Cloudflare CDN/DDoS (free tier) | $0 |

### App Deployment & Distribution

| Item | Cost |
|---|---|
| Expo / EAS Build (free tier) | $0 (limited builds, queue wait) |
| Apple Developer Program | $99/year (~$8.25/month) |
| Google Play Developer | $25 one-time |
| Push Notifications (Firebase Cloud Messaging) | $0 |

**Build strategy:** Use Expo free tier for development. For production releases, use EAS free tier (low priority queue, ~30 min wait) or build locally. 2–4 builds per month is fine for the free tier.

### Email & Transactional

| Item | Cost |
|---|---|
| Resend (transactional email, free tier) | $0 (up to 100 emails/day) |
| Or Brevo free tier | $0 (300 emails/day) |

### Monitoring & Error Tracking

| Item | Cost |
|---|---|
| Sentry (free tier) | $0 (5K errors/month) |
| UptimeRobot (free tier) | $0 (50 monitors) |
| Custom logging to PostgreSQL | $0 |

---

## 4. Total Monthly Cost Breakdown

### Development (Pre-Launch)

| Item | Monthly Cost |
|---|---|
| Netcup VPS 1000 G12 | €8.45 |
| Domain (kalei.ai) | ~€5.00 |
| OpenRouter API (dev/testing) | ~€5 |
| Expo Free Tier | €0 |
| Cloudflare, Sentry, email | €0 |
| **Total** | **~€18.50/month** |

**Upfront costs:** Apple Developer ($99) + Google Play ($25) + Domain (~$55/year) = **~€180 one-time**

### At Launch (0–500 users, ~50 DAU)

All features ship in v1: Mirror, Turn, Lens, Spectrum, Rehearsal, Ritual, Evidence Wall, Guide. Assuming 50 daily active users, ~200 registered:

| Item | Monthly Cost |
|---|---|
| Netcup VPS 1000 G12 | €8.45 |
| Domain | ~€5.00 |
| AI via OpenRouter (~50 active × $0.04 avg) | ~€2.00 |
| Expo Free Tier | €0 |
| Infrastructure (Cloudflare, etc.) | €0 |
| **Total** | **~€15.50/month** |

### At Traction (500–2,000 users, ~200 DAU)

| Item | Monthly Cost |
|---|---|
| Netcup VPS 2000 G12 (upgrade) | €15.59 |
| Domain | ~€5.00 |
| AI via OpenRouter (~200 active × $0.04 avg) | ~€8.00 |
| Expo Starter (if needed for OTA updates) | €19.00 |
| Email (may need paid tier) | €0–10 |
| **Total** | **~€48–58/month** |

### At Growth (2,000–10,000 users, ~1,000 DAU)

| Item | Monthly Cost |
|---|---|
| Netcup VPS 4000 G12 | €26.18 |
| Domain | ~€5.00 |
| AI via OpenRouter (~1,000 active × $0.04 avg) | ~€40.00 |
| Expo Production plan | €99.00 |
| Email paid tier | ~€20 |
| Sentry paid (if needed) | ~€26 |
| **Total** | **~€216/month** |

AI cost is now only ~19% of total spend at 1,000 DAU (down from ~60% under the Haiku-first plan). Infrastructure and app store tooling become the dominant costs at scale.

---

## 5. Pricing Reevaluation

### The Old Price: $7.99/month (Prism)

Based on the cost model above, let's check if this works:

**At 50 DAU (~10 paying subscribers):**
- Revenue: 10 × $7.99 = $79.90
- Costs: ~$28
- **Margin: +$52 (65%)**

**At 200 DAU (~40 paying subscribers @ 20% conversion):**
- Revenue: 40 × $7.99 = $319.60
- Costs: ~$100
- **Margin: +$220 (69%)**

**At 1,000 DAU (~150 paying subscribers @ 15% conversion):**
- Revenue: 150 × $7.99 = $1,198.50
- Costs: ~$425
- **Margin: +$773 (65%)**

The margins are healthy. But $7.99 feels like a lot for a brand-new app from an unknown brand in a competitive wellness space. Users compare against Headspace ($12.99), Calm ($14.99), but those have massive brand recognition and content libraries.

### The New Price: $4.99/month (Prism)

**Why $4.99:**
- Psychological barrier is much lower — impulse-buy territory
- Significantly undercuts major competitors while offering AI personalization they don't have
- At ~$0.08/month cost per Prism subscriber (including full Guide coaching), the margin is **98%**
- Annual option: $39.99/year ($3.33/month) — strong incentive to commit
- Free tier remains generous enough to demonstrate value (3 Turns/day, 2 Mirror/week, basic Guide)

**Revised projections at $4.99 (with OpenRouter + DeepSeek V3.2 AI strategy):**

| Scale | Paying Users | Monthly Revenue | Monthly Cost | Margin |
|---|---|---|---|---|
| Launch (~50 DAU) | 15 (higher conversion at lower price) | $74.85 | ~$16 | +$59 (79%) |
| Traction (~200 DAU) | 60 | $299.40 | ~$53 | +$246 (82%) |
| Growth (~1,000 DAU) | 250 | $1,247.50 | ~$216 | +$1,032 (83%) |

The AI cost reduction transforms the unit economics. Margins now exceed 79% at every stage, and break-even comes faster.

### Alternative: Tiered Pricing

| Tier | Price | What You Get |
|---|---|---|
| **Free** | $0 | 3 Turns/day, 2 Mirror/week, basic Lens, 30-day Gallery |
| **Prism** | $4.99/mo | Unlimited Turns + Mirror, advanced reframe styles, full Gallery, fragment tracking |
| **Prism+** | $9.99/mo | Everything in Prism + full Spectrum dashboard, weekly/monthly AI insights, export, priority processing |

This is smart because Spectrum is the most expensive feature (batch AI analysis of historical data) and the most valuable retention tool. Gating it behind a higher tier means only your most engaged (and willing-to-pay) users generate that cost, and they're paying for it.

---

## 6. Revenue Milestones & Sustainability

### Break-Even Analysis

**Monthly fixed costs (at launch):** ~€14 (VPS + domain)
**Variable cost per active user:** ~€0.04

Break-even on fixed costs alone: **3 Prism subscribers at $4.99** cover the infrastructure.

To cover Apple's annual fee ($99) and Google ($25 amortized): add ~$10/month → total of **5 subscribers** to fully break even.

### Path to Sustainability

| Milestone | Users | Paying | MRR | Costs | Profit |
|---|---|---|---|---|---|
| Month 3 | 100 | 5 | $25 | $17 | +$8 |
| Month 6 | 500 | 30 | $150 | $22 | +$128 |
| Month 9 | 1,500 | 80 | $400 | $35 | +$365 |
| Month 12 | 3,000 | 200 | $1,000 | $60 | +$940 |
| Month 18 | 8,000 | 600 | $3,000 | $150 | +$2,850 |

The model is profitable from **month 3** with just 5 paying subscribers. The 90% AI cost reduction means Kalei reaches profitability immediately at launch rather than needing a 4–5 month runway.

---

## 7. Technical Architecture Summary

```
┌─────────────────────────────────────────────────────┐
│                   CLIENTS                            │
│         React Native (iOS + Android)                 │
│              via Expo / EAS                          │
└──────────────────┬──────────────────────────────────┘
                   │ HTTPS
                   ▼
┌─────────────────────────────────────────────────────┐
│              CLOUDFLARE (Free Tier)                  │
│        DNS · CDN · DDoS Protection · SSL            │
└──────────────────┬──────────────────────────────────┘
                   │
                   ▼
┌─────────────────────────────────────────────────────┐
│        NETCUP VPS 1000 G12 (€8.45/mo)              │
│                                                      │
│  ┌──────────┐  ┌───────────┐  ┌──────────────────┐  │
│  │  Nginx   │→ │  Node.js  │→ │   PostgreSQL 16  │  │
│  │ (proxy)  │  │  API      │  │   (all app data) │  │
│  └──────────┘  └─────┬─────┘  └──────────────────┘  │
│                      │         ┌──────────────────┐  │
│                      │         │     Redis        │  │
│                      │         │  (cache/sessions)│  │
│                      │         └──────────────────┘  │
└──────────────────────┼──────────────────────────────┘
                       │ API Calls
                       ▼
        ┌──────────────────────────────┐
        │     OPENROUTER GATEWAY       │
        │     (single API, one key)    │
        │                              │
        │  ┌────────────────────────┐  │
        │  │ PRIMARY: DeepSeek V3.2 │  │
        │  │ via DeepInfra/Fireworks │  │
        │  │ (US/EU infrastructure) │  │
        │  │                        │  │
        │  │ All features:          │  │
        │  │ • Mirror fragments     │  │
        │  │ • Kaleidoscope reframes│  │
        │  │ • Lens affirmations    │  │
        │  │ • Crisis detection     │  │
        │  │ • Guide coaching       │  │
        │  │ • Spectrum analysis    │  │
        │  │                        │  │
        │  │ $0.26/$0.38 per MTok   │  │
        │  └────────────────────────┘  │
        │              │               │
        │    (automatic failover)      │
        │              │               │
        │  ┌────────────────────────┐  │
        │  │ FALLBACK: Claude Haiku │  │
        │  │ 4.5 (Anthropic)       │  │
        │  │ $1.00/$5.00 per MTok  │  │
        │  │ Activated on outage   │  │
        │  └────────────────────────┘  │
        └──────────────────────────────┘
```

### Key Technical Decisions

**Auth:** Custom JWT-based auth built into our Node.js API. Uses bcrypt for password hashing, short-lived access tokens (15 min) + long-lived refresh tokens stored in PostgreSQL. Social login (Apple Sign-In, Google) via their SDKs — free.

**Database schema:** PostgreSQL with Row Level Security policies. Tables for users, mirror_sessions, mirror_fragments, turns, lens_goals, spectrum_analyses. All user content encrypted at rest (PostgreSQL `pgcrypto` extension).

**AI request pipeline:**
1. Client sends user text to our API
2. API constructs prompt with cached system prompt + user context
3. API calls DeepSeek V3.2 via OpenRouter (pinned to DeepInfra/Fireworks), streams response back to client
4. If primary provider fails, OpenRouter automatically fails over to Claude Haiku 4.5
5. API logs token usage for cost tracking
6. Response stored in PostgreSQL for Spectrum analysis

**Rate limiting:** Redis-based. Free tier: 3 Turns/day, 2 Mirror/week enforced server-side. Prism: unlimited but soft-capped at 50 Turns/day to prevent abuse (99.9% of users will never hit this).

**Prompt caching strategy:** System prompts for each feature (Mirror, Kaleidoscope, Lens, Guide) are designed to be identical across users. Only the user's specific content changes. DeepInfra supports prompt caching with ~20% discount on cached input tokens ($0.216/M vs $0.26/M). While less dramatic than Anthropic's 90% cache discount, the base pricing is already so low that effective costs remain minimal.

---

## 8. Cost Control Safeguards

These prevent a surprise API bill from killing the project:

1. **Hard spending cap** on OpenRouter dashboard (start at $20/month, increase as revenue grows)
2. **Per-user daily token budget** tracked in Redis. If a user somehow generates excessive requests, they get a "take a break" message (fits the wellness brand perfectly)
3. **Graceful degradation:** If API budget is 80% consumed, route Lens affirmations to local template system (pre-written affirmations, no AI needed). Mirror and Kaleidoscope get priority for remaining budget.
4. **Automatic failover:** OpenRouter handles provider switching transparently. If DeepInfra has an outage, requests route to Fireworks or Claude Haiku automatically — no code changes needed.
5. **Monitor daily:** Simple Telegram bot alerts if daily API spend exceeds threshold

---

## 9. Startup Budget Allocation

With a maximum €2,000 to spend wisely:

| Category | Amount | What It Covers |
|---|---|---|
| Apple Developer Account | €99 | Annual fee, required for App Store |
| Google Play Developer | €25 | One-time fee |
| Domain (kalei.ai, 1 year) | ~€55 | Annual registration |
| Netcup VPS (6 months prepaid) | ~€51 | Runway for half a year of hosting |
| OpenRouter API credits (initial deposit) | €50 | Covers dev + testing + first ~1,000+ active user-months at DeepSeek V3.2 pricing |
| Design assets (fonts, if not free) | €0–50 | Inter + custom weight = free. Icon set if needed. |
| Contingency | ~€120 | Unexpected costs |
| **Total startup spend** | **~€400–450** | |
| **Remaining reserve** | **~€1,550–1,600** | 100+ months of launch-scale operating costs |

This means the €2,000 budget gives us effectively **unlimited runway** at launch-scale costs (~€16/month). Even without a single paying customer, we could operate for over 8 years. The AI cost reduction transformed our runway from "comfortable" to "virtually infinite" at early scale.

---

## 10. When to Scale (And What Changes)

| Trigger | Action | Cost Impact |
|---|---|---|
| >200 concurrent connections | Upgrade to VPS 2000 (€15.59) | +€7/month |
| >500 DAU | Add Redis Cluster or separate DB VPS | +€5–8/month |
| >600 DAU | Evaluate self-hosted Qwen3-30B-A3B on GPU (~$245/mo) | Cheaper than API at this volume, full data control |
| >2,000 DAU | Upgrade to VPS 4000 (€26.18) | +€10/month |
| >5,000 DAU | Introduce tiered model routing (different models per feature) | Saves ~20–30% on AI costs at scale |
| >10,000 DAU | Consider second VPS for API/DB separation | Architecture change |
| >$2,000/month revenue | Consider dedicated server or managed Postgres | Comfort/reliability upgrade |

The beauty of this architecture is that **nothing changes architecturally as we scale** — we just give the same VPS more resources, and the API costs scale linearly and predictably with users.

---

## 11. Competitive Cost Comparison

To put this in perspective — what would this cost on "standard" startup infrastructure?

| Our Stack | "Normal" Startup Stack | Monthly Cost |
|---|---|---|
| Netcup VPS (€8.45) | AWS EC2 t3.medium | $35–50 |
| PostgreSQL on VPS ($0) | Supabase Pro or RDS | $25–50 |
| Redis on VPS ($0) | Redis Cloud or ElastiCache | $15–30 |
| Cloudflare free ($0) | AWS CloudFront + ALB | $20–40 |
| DeepSeek V3.2 via OpenRouter (~$2) | Claude/GPT-4 API ($50+) | 96% cheaper |
| **Our total: ~$16/mo** | **Their total: ~$120–200/mo** | |

We're running at **8–13%** of what a "typical" startup would spend by self-hosting on a European VPS and using cost-optimized AI routing instead of defaulting to AWS/GCP + expensive frontier models.

---

## 12. Final Pricing Recommendation

| | Free | Prism | Prism+ |
|---|---|---|---|
| **Price** | $0 | **$4.99/month** | **$9.99/month** |
| | | $39.99/year | $79.99/year |
| Turns/day | 3 | Unlimited | Unlimited |
| Mirror/week | 2 | Unlimited | Unlimited |
| Lens | Basic | Full | Full |
| Reframe styles | 1 (Compassionate) | All 4 | All 4 |
| Gallery | 30 days | Full history | Full history |
| Fragment tracking | No | Yes | Yes |
| Spectrum | No | No | **Full dashboard** |
| Weekly AI insights | No | No | **Yes** |
| Growth trajectory | No | No | **Yes** |
| Export | No | Basic | Full |
| **Our cost per user** | ~$0.02 | ~$0.06 | ~$0.08 |
| **Margin** | N/A (acquisition) | **99%** | **99%** |

### Why This Works

At **$4.99**, Kalei is:
- Cheaper than Headspace ($12.99), Calm ($14.99), Woebot (free but limited)
- More personalized than any of them (AI-powered, not pre-recorded content)
- Profitable from subscriber #6
- Self-sustaining from month ~5
- Fully funded for 12+ months on a €2,000 budget even with zero revenue

The model scales cleanly because **AI costs are the only meaningful variable cost**, and they scale linearly with usage at a rate that our pricing covers with 98%+ margins on the AI component. Even at scale, total infrastructure costs stay manageable because the OpenRouter + DeepInfra strategy keeps per-user AI spend under $0.10/month.

---

*Last updated: February 2026*
*All prices include VAT where applicable. USD/EUR conversions at approximate current rates.*