This chapter walks you step by step through setting up the infrastructure of a modern SaaS. For each service: what it is, how to set it up, how much it costs. Reading time: 15 minutes.

Overview

A typical modern SaaS uses 7 to 8 services.

Supabase: database + authentication + storage 2. Vercel: hosting and deployment 3. Domain name: your app's address (Namecheap, OVH, etc.)
Stripe: payments and subscriptions 5. Resend: transactional emails
Upstash: rate limiting (anti-abuse) 7. Anthropic: generative AI (if your app uses AI) 8. Sentry: error monitoring in production

All of them ship a free plan that's enough to develop with. You only pay when you move to production with real users.

Prerequisites: Docker and Node.js

Before configuring the services, two tools on your machine.

Docker (for the local database)

Docker runs a Supabase database on your computer during development. You never touch production data.

On macOS:

Download Docker Desktop from docker.com/products/docker-desktop, free for individual use
Install it like any other application
Launch Docker Desktop, it runs in the background (whale icon in the menu bar)

On Windows:

Download Docker Desktop from docker.com/products/docker-desktop
The installer enables WSL 2 (Windows Subsystem for Linux) if needed, accept it
Restart if asked, then launch Docker Desktop

Check that Docker is running:

docker --version

Docker Desktop uses RAM (2-4 GB). If your computer has less than 8 GB of RAM, it can slow things down. You can close Docker when you're not coding.

Node.js (for the dev tools)

Node.js runs the project's tooling (Next.js dev server, Supabase migrations, etc.). Not required for Claude Code itself, but essential as soon as you work on a real project.

On macOS, open Terminal and paste:

curl -fsSL https://fnm.vercel.app/install | bash && fnm install 22

Close and reopen Terminal, then check:

node --version

You should see v22.x.x.

On Windows:

Go to nodejs.org
Download the LTS installer
Run the installer, check "Add to PATH" when prompted
Open PowerShell and type node --version

Common Windows error: if node --version doesn't work after the install, restart your computer. The PATH needs a reboot to take effect.

1. Supabase, database, Auth, Storage

What it is: your PostgreSQL database, your auth system (login, register, OAuth), and your file storage. All in one, with a web admin interface.

Setup steps

Create an account on supabase.com
Create a new project (pick the eu-west region for France)
Note the URL and API keys (Dashboard → Settings → API)
Locally, install the CLI: npx supabase init then npx supabase start (Docker must be running)

Environment variables

NEXT_PUBLIC_SUPABASE_URL=https://xxxxx.supabase.co
NEXT_PUBLIC_SUPABASE_ANON_KEY=eyJhbGci...
SUPABASE_SERVICE_ROLE_KEY=eyJhbGci...

Pricing

Plan	Price	Limits	For whom
Free	$0/mo	500 MB storage, 50K users, 2 projects	Development
Pro	$25/mo	8 GB storage, 100K users, daily backups	Production

Gotcha: the Free plan pauses your project after 7 days of inactivity. Your users won't be able to sign in anymore. Move to Pro as soon as you have real users.

2. Vercel, hosting and deployment

What it is: the host that runs your Next.js app. Every git push triggers an automatic deploy. Zero server config.

Setup steps

Create an account on vercel.com (sign in with GitHub)
Click "New Project" and import your GitHub repository
Vercel automatically detects it's Next.js
Add your environment variables in Settings → Environment Variables
First automatic deploy in 2 minutes

Key features

Deploy Preview: every Pull Request gets its own preview URL
Cron Jobs: scheduled tasks (sending emails, sync, reminders) defined in vercel.json
Analytics: Web Vitals performance metrics

Pricing

Plan	Price	Limits	For whom
Hobby	$0/mo	1 personal project, functions up to 60s, 1 cron/day max	Testing
Pro	$20/mo	Unlimited projects, functions up to 300s (800s with Fluid Compute), unlimited crons	Production

3. Domain name

What it is: your app's address (e.g. myapp.com). You can buy it from any registrar.

Steps

Pick a registrar: Namecheap, OVH, Google Domains, Gandi...
Search and buy your domain name
In Vercel: Settings → Domains → add your domain
Copy the DNS records Vercel gives you to your registrar
Wait 24-48h for DNS propagation

Pricing

.com: around $10/year (first year often on promo at $7)
.fr: around $10-12/year
.app: around $15/year
WhoisGuard (privacy protection): free at Namecheap

4. Stripe, payments

What it is: the payment platform that handles your subscriptions. No monthly subscription, Stripe only takes a cut when someone pays.

Setup steps

Create an account on stripe.com
Turn on Test mode first (Dashboard → toggle "Test mode")
Create your products and prices (Products → Add product)
Grab your API keys (Developers → API keys)
Set up the webhook: Developers → Webhooks → add your URL + /api/webhooks/stripe
Locally: stripe listen --forward-to localhost:3000/api/webhooks/stripe

Environment variables

STRIPE_SECRET_KEY=sk_test_xxx
STRIPE_WEBHOOK_SECRET=whsec_xxx
STRIPE_PRICE_PRO_MONTHLY=price_xxx

Pricing

Type	Cost
Stripe subscription	$0, free as long as nobody pays
Per-payment fee (Europe)	1.5% + €0.25 per transaction
Stripe Billing (subscriptions)	+0.7% of the billed volume

Real-world cost: if you have 10 Pro customers at €29/mo, Stripe takes about €5/month total. It's negligible.

5. Resend, transactional emails

What it is: the service that sends your automated emails (welcome, reminders, weekly recaps). Modern UI, easy integration with React Email.

Setup steps

Create an account on resend.com
Add your domain: Settings → Domains → Add domain
Set up 3 DNS records at your registrar
Verify the domain (a few minutes)
Grab your API key: API Keys → Create

Environment variable

RESEND_API_KEY=re_xxx

Pricing

Plan	Price	Limits
Free	$0/mo	3,000 emails/mo, 1 day of log retention
Pro	$20/mo	50,000 emails/mo, full analytics

3,000 free emails/month = more than enough to get started. Even with 100 active users, you stay inside the free quota.

6. Upstash, rate limiting (anti-abuse)

What it is: a serverless Redis that prevents abuse. Without it, a user could spam your AI API and cost you hundreds of dollars in tokens.

Setup steps

Create an account on upstash.com
Create a Redis database (region: eu-west-1)
Grab the URL and token (Database → Details)

Environment variables

UPSTASH_REDIS_REST_URL=https://xxx.upstash.io
UPSTASH_REDIS_REST_TOKEN=xxx

Pricing

Free: 500,000 commands/month. You'll probably never go past this quota, even with 1,000 users.
Pay-as-you-go: $0.2 per 100,000 commands beyond that.

7. Anthropic, Claude API (if your app uses AI)

What it is: the API that powers AI content generation in your app.

Don't confuse them: the Claude Max subscription ($200/mo in 2026) gives you access to Claude Code for development. The Anthropic API is a separate service, billed by usage, for embedding AI inside your app.

Steps

Create an account on console.anthropic.com
Add a payment method (required even for testing)
Create an API key: API Keys → Create Key
Set a monthly budget cap in Settings → Billing (to avoid surprises)

Environment variable

ANTHROPIC_API_KEY=sk-ant-xxx

Pricing (Claude Sonnet 4.6, 2026 rates)

Input: $3 per million tokens
Output: $15 per million tokens
In practice: a content generation (3 variants) costs around $0.02-0.05

Realistic monthly estimate: - 10 active users, 20 generations/month each = around $10-20/month - 100 active users = around $50-100/month - Set a budget cap in the console to avoid surprises

8. Sentry, error monitoring

What it is: automatically captures production errors and reports them. Without it, you don't know when your app crashes for your users.

Steps

Create an account on sentry.io
Create a Next.js project
Follow the install wizard (it adds the config files automatically)

Environment variables

NEXT_PUBLIC_SENTRY_DSN=https://xxx@sentry.io/xxx
SENTRY_ORG=your-org
SENTRY_PROJECT=your-project
SENTRY_AUTH_TOKEN=sntrys_xxx

Pricing

Developer ($0/mo): 5,000 errors/mo, 1 user. Enough to get started.
Team ($26/mo): 50,000 errors/mo, unlimited users.

Cost recap

Development phase (0 users)

Service	Cost
Supabase Free	$0
Vercel Hobby	$0
.com domain	~$0.80/mo ($10/year)
Stripe	$0 (no transactions)
Resend Free	$0
Upstash Free	$0
Anthropic (your tests)	~$5/mo
Sentry Developer	$0
Claude Code (Max)	$200/mo
Total dev phase	~$206/mo (of which $200 for Claude Code)

Infrastructure costs almost nothing in development. The only meaningful cost is Claude Code itself ($200/mo on the 2026 Max plan). Every service has a free plan that's enough to develop with.

Production phase (10-50 users)

Service	Cost
Supabase Pro	$25/mo
Vercel Pro	$20/mo
Domain	~$1/mo
Stripe (fees)	~$5/mo
Resend Free	$0
Upstash Free	$0
Anthropic	$20-50/mo
Sentry Developer	$0
Total production	~$75-105/mo

Break-even point: if your subscription is €29/mo, you need 4 to 5 paying customers to cover all infrastructure costs. From the 6th customer onwards, you're profitable.

The recommended install order

Phase 1, development (day 1)

Supabase → your database and auth are working
Vercel → your app is deployed automatically
Sentry → you see errors from day one

Phase 2, features (days 2-3)

Resend → your automated emails work
Upstash → your API is protected against abuse
Anthropic API → your AI is integrated (if applicable)

Phase 3, launch (day 4+)

Stripe → your users can pay
Domain → your app has its own address

Quick-start recipe for a first SaaS

If you're starting your very first project, don't try to wire everything at once. You'll drown.

The minimal stack that scales to 1,000 users:

Supabase (database + auth): $25/mo
Vercel (hosting): $20/mo if you move to Pro, free otherwise
Resend (emails): free up to 3,000 emails/mo
Stripe (payments): $0 flat, commission only

Total budget: around €25/mo to start, climbing to €45-50/mo when you move Vercel to Pro. The rest (Upstash, Sentry, Anthropic API, custom domain) comes when you actually need it, not before.

Takeaway: every service has a free plan that's enough to develop with. You only pay in production, and the break-even point is reached at 4 to 5 paying customers. The infrastructure of a modern SaaS costs less than a Netflix subscription.

This chapter walks you step by step through setting up the infrastructure of a modern SaaS. For each service: what it is, how to set it up, how much it costs. Reading time: 15 minutes.

Overview

A typical modern SaaS uses 7 to 8 services.

Supabase: database + authentication + storage 2. Vercel: hosting and deployment 3. Domain name: your app's address (Namecheap, OVH, etc.)
Stripe: payments and subscriptions 5. Resend: transactional emails
Upstash: rate limiting (anti-abuse) 7. Anthropic: generative AI (if your app uses AI) 8. Sentry: error monitoring in production

All of them ship a free plan that's enough to develop with. You only pay when you move to production with real users.

Prerequisites: Docker and Node.js

Before configuring the services, two tools on your machine.

Docker (for the local database)

Docker runs a Supabase database on your computer during development. You never touch production data.

On macOS:

Download Docker Desktop from docker.com/products/docker-desktop, free for individual use
Install it like any other application
Launch Docker Desktop, it runs in the background (whale icon in the menu bar)

On Windows:

Download Docker Desktop from docker.com/products/docker-desktop
The installer enables WSL 2 (Windows Subsystem for Linux) if needed, accept it
Restart if asked, then launch Docker Desktop

Check that Docker is running:

docker --version

Docker Desktop uses RAM (2-4 GB). If your computer has less than 8 GB of RAM, it can slow things down. You can close Docker when you're not coding.

Node.js (for the dev tools)

Node.js runs the project's tooling (Next.js dev server, Supabase migrations, etc.). Not required for Claude Code itself, but essential as soon as you work on a real project.

On macOS, open Terminal and paste:

curl -fsSL https://fnm.vercel.app/install | bash && fnm install 22

Close and reopen Terminal, then check:

node --version

You should see v22.x.x.

On Windows:

Go to nodejs.org
Download the LTS installer
Run the installer, check "Add to PATH" when prompted
Open PowerShell and type node --version

Common Windows error: if node --version doesn't work after the install, restart your computer. The PATH needs a reboot to take effect.

1. Supabase, database, Auth, Storage

What it is: your PostgreSQL database, your auth system (login, register, OAuth), and your file storage. All in one, with a web admin interface.

Setup steps

Create an account on supabase.com
Create a new project (pick the eu-west region for France)
Note the URL and API keys (Dashboard → Settings → API)
Locally, install the CLI: npx supabase init then npx supabase start (Docker must be running)

Environment variables

NEXT_PUBLIC_SUPABASE_URL=https://xxxxx.supabase.co
NEXT_PUBLIC_SUPABASE_ANON_KEY=eyJhbGci...
SUPABASE_SERVICE_ROLE_KEY=eyJhbGci...

Pricing

Plan	Price	Limits	For whom
Free	$0/mo	500 MB storage, 50K users, 2 projects	Development
Pro	$25/mo	8 GB storage, 100K users, daily backups	Production

Gotcha: the Free plan pauses your project after 7 days of inactivity. Your users won't be able to sign in anymore. Move to Pro as soon as you have real users.

2. Vercel, hosting and deployment

What it is: the host that runs your Next.js app. Every git push triggers an automatic deploy. Zero server config.

Setup steps

Create an account on vercel.com (sign in with GitHub)
Click "New Project" and import your GitHub repository
Vercel automatically detects it's Next.js
Add your environment variables in Settings → Environment Variables
First automatic deploy in 2 minutes

Key features

Deploy Preview: every Pull Request gets its own preview URL
Cron Jobs: scheduled tasks (sending emails, sync, reminders) defined in vercel.json
Analytics: Web Vitals performance metrics

Pricing

Plan	Price	Limits	For whom
Hobby	$0/mo	1 personal project, functions up to 60s, 1 cron/day max	Testing
Pro	$20/mo	Unlimited projects, functions up to 300s (800s with Fluid Compute), unlimited crons	Production

3. Domain name

What it is: your app's address (e.g. myapp.com). You can buy it from any registrar.

Steps

Pick a registrar: Namecheap, OVH, Google Domains, Gandi...
Search and buy your domain name
In Vercel: Settings → Domains → add your domain
Copy the DNS records Vercel gives you to your registrar
Wait 24-48h for DNS propagation

Pricing

.com: around $10/year (first year often on promo at $7)
.fr: around $10-12/year
.app: around $15/year
WhoisGuard (privacy protection): free at Namecheap

4. Stripe, payments

What it is: the payment platform that handles your subscriptions. No monthly subscription, Stripe only takes a cut when someone pays.

Setup steps

Create an account on stripe.com
Turn on Test mode first (Dashboard → toggle "Test mode")
Create your products and prices (Products → Add product)
Grab your API keys (Developers → API keys)
Set up the webhook: Developers → Webhooks → add your URL + /api/webhooks/stripe
Locally: stripe listen --forward-to localhost:3000/api/webhooks/stripe

Environment variables

STRIPE_SECRET_KEY=sk_test_xxx
STRIPE_WEBHOOK_SECRET=whsec_xxx
STRIPE_PRICE_PRO_MONTHLY=price_xxx

Pricing

Type	Cost
Stripe subscription	$0, free as long as nobody pays
Per-payment fee (Europe)	1.5% + €0.25 per transaction
Stripe Billing (subscriptions)	+0.7% of the billed volume

Real-world cost: if you have 10 Pro customers at €29/mo, Stripe takes about €5/month total. It's negligible.

5. Resend, transactional emails

What it is: the service that sends your automated emails (welcome, reminders, weekly recaps). Modern UI, easy integration with React Email.

Setup steps

Create an account on resend.com
Add your domain: Settings → Domains → Add domain
Set up 3 DNS records at your registrar
Verify the domain (a few minutes)
Grab your API key: API Keys → Create

Environment variable

RESEND_API_KEY=re_xxx

Pricing

Plan	Price	Limits
Free	$0/mo	3,000 emails/mo, 1 day of log retention
Pro	$20/mo	50,000 emails/mo, full analytics

3,000 free emails/month = more than enough to get started. Even with 100 active users, you stay inside the free quota.

6. Upstash, rate limiting (anti-abuse)

What it is: a serverless Redis that prevents abuse. Without it, a user could spam your AI API and cost you hundreds of dollars in tokens.

Setup steps

Create an account on upstash.com
Create a Redis database (region: eu-west-1)
Grab the URL and token (Database → Details)

Environment variables

UPSTASH_REDIS_REST_URL=https://xxx.upstash.io
UPSTASH_REDIS_REST_TOKEN=xxx

Pricing

Free: 500,000 commands/month. You'll probably never go past this quota, even with 1,000 users.
Pay-as-you-go: $0.2 per 100,000 commands beyond that.

7. Anthropic, Claude API (if your app uses AI)

What it is: the API that powers AI content generation in your app.

Steps

Create an account on console.anthropic.com
Add a payment method (required even for testing)
Create an API key: API Keys → Create Key
Set a monthly budget cap in Settings → Billing (to avoid surprises)

Environment variable

ANTHROPIC_API_KEY=sk-ant-xxx

Pricing (Claude Sonnet 4.6, 2026 rates)

Input: $3 per million tokens
Output: $15 per million tokens
In practice: a content generation (3 variants) costs around $0.02-0.05

Realistic monthly estimate: - 10 active users, 20 generations/month each = around $10-20/month - 100 active users = around $50-100/month - Set a budget cap in the console to avoid surprises

8. Sentry, error monitoring

What it is: automatically captures production errors and reports them. Without it, you don't know when your app crashes for your users.

Steps

Create an account on sentry.io
Create a Next.js project
Follow the install wizard (it adds the config files automatically)

Environment variables

NEXT_PUBLIC_SENTRY_DSN=https://xxx@sentry.io/xxx
SENTRY_ORG=your-org
SENTRY_PROJECT=your-project
SENTRY_AUTH_TOKEN=sntrys_xxx

Pricing

Developer ($0/mo): 5,000 errors/mo, 1 user. Enough to get started.
Team ($26/mo): 50,000 errors/mo, unlimited users.

Cost recap

Development phase (0 users)

Service	Cost
Supabase Free	$0
Vercel Hobby	$0
.com domain	~$0.80/mo ($10/year)
Stripe	$0 (no transactions)
Resend Free	$0
Upstash Free	$0
Anthropic (your tests)	~$5/mo
Sentry Developer	$0
Claude Code (Max)	$200/mo
Total dev phase	~$206/mo (of which $200 for Claude Code)

Infrastructure costs almost nothing in development. The only meaningful cost is Claude Code itself ($200/mo on the 2026 Max plan). Every service has a free plan that's enough to develop with.

Production phase (10-50 users)

Service	Cost
Supabase Pro	$25/mo
Vercel Pro	$20/mo
Domain	~$1/mo
Stripe (fees)	~$5/mo
Resend Free	$0
Upstash Free	$0
Anthropic	$20-50/mo
Sentry Developer	$0
Total production	~$75-105/mo

Break-even point: if your subscription is €29/mo, you need 4 to 5 paying customers to cover all infrastructure costs. From the 6th customer onwards, you're profitable.

The recommended install order

Phase 1, development (day 1)

Supabase → your database and auth are working
Vercel → your app is deployed automatically
Sentry → you see errors from day one

Phase 2, features (days 2-3)

Resend → your automated emails work
Upstash → your API is protected against abuse
Anthropic API → your AI is integrated (if applicable)

Phase 3, launch (day 4+)

Stripe → your users can pay
Domain → your app has its own address

Quick-start recipe for a first SaaS

If you're starting your very first project, don't try to wire everything at once. You'll drown.

The minimal stack that scales to 1,000 users:

Supabase (database + auth): $25/mo
Vercel (hosting): $20/mo if you move to Pro, free otherwise
Resend (emails): free up to 3,000 emails/mo
Stripe (payments): $0 flat, commission only

Total budget: around €25/mo to start, climbing to €45-50/mo when you move Vercel to Pro. The rest (Upstash, Sentry, Anthropic API, custom domain) comes when you actually need it, not before.