What Is a Tech Stack (and Why You Should Care)
A "tech stack" is the combination of tools and services that power your app. Even if you are using an AI tool to write all the code, your app still depends on multiple layers of technology working together. Understanding these layers helps you make better decisions, troubleshoot problems faster, and avoid costly mistakes.
Think of it like building a house. You don't need to know how to lay bricks, but you should understand that a house needs a foundation, walls, plumbing, electrical, and a roof. If you skip the foundation, everything else is unstable. The same is true for software.
The Six Layers of a Modern Tech Stack
Every web application, whether built by hand or with AI, consists of these six layers:
- Frontend — What users see and interact with. This is the visual interface: buttons, forms, pages, navigation. Most vibe-coded apps use React (through Next.js), which your AI tool generates automatically.
- Backend and Database — Where your data lives and how it is processed. When a user creates an account, submits a form, or saves a document, that information needs to be stored somewhere and retrieved later.
- Authentication — How users prove who they are. Login, signup, password reset, social login with Google or GitHub. This is the layer that keeps each user's data separate and secure.
- Payments — How you charge for your product. If your app has a paid tier, you need a payment processor to handle credit cards, subscriptions, invoices, and refunds.
- Hosting — Where your app runs on the internet. Someone's computer somewhere is serving your website to visitors. Hosting providers handle the servers so you don't have to.
- Analytics — How you understand what users do. Page views, feature usage, conversion rates, error rates. Without analytics, you are building in the dark.
The Safe Default Stack for Beginners
If you are building your first vibe-coded app, here is the stack that gives you the fewest headaches. These tools work well together, have generous free tiers, and are the ones AI coding tools know best.
| Layer | Recommended Tool | Why This One |
|---|---|---|
| AI Tool | Lovable or Cursor | Lovable for no-code beginners, Cursor for anyone with some technical comfort |
| Database | Supabase | Built-in auth, generous free tier, excellent AI tool integration |
| Auth | Clerk | Easiest setup, beautiful pre-built components, social logins out of the box |
| Payments | Stripe | Industry standard, best documentation, every AI tool knows how to integrate it |
| Hosting | Vercel | Free tier, automatic deploys, great performance, built for Next.js |
| Analytics | PostHog | Free tier with session recordings, feature flags, and product analytics |
This stack can take you from zero users to thousands. You don't need to overthink your choices at the beginning — these defaults work for the vast majority of SaaS apps, marketplaces, and web tools.
Cloud vs. Local AI
Most vibe coding tools run in the cloud: your code is processed on someone else's servers. This is fine for most projects, but there are reasons you might want to run AI locally.
Cloud-hosted tools (Cursor, Lovable, Bolt) offer the best AI models, require no setup, and work on any computer. The trade-off is that your code is sent to external servers for processing. For personal projects and most startups, this is perfectly acceptable.
Local AI tools (Ollama + Continue) run AI models on your own machine. Your code never leaves your computer, which matters if you are working with sensitive data, proprietary algorithms, or in a regulated industry. The trade-off is that local models are generally less capable than cloud models, and you need a powerful computer (ideally with a modern GPU) to run them.
For most vibe coders, cloud tools are the right choice. Consider local tools if privacy is a hard requirement for your project, or if you want to experiment with AI without ongoing subscription costs.
Costs at Different Scales
One of the best things about the modern vibe coding stack is that costs scale with usage. You pay almost nothing when you have no users, and costs grow gradually as your app succeeds. Here is what a typical vibe-coded SaaS costs at different stages:
| Stage | Monthly Cost | What You're Paying For |
|---|---|---|
| Building (0 users) | $0 – $20 | AI tool subscription (Cursor Pro at $20/mo or Lovable free tier). Everything else is free tier. |
| Launched (100 users) | $20 – $50 | AI tool + possibly Supabase Pro ($25/mo) if you need more database storage. |
| Growing (1,000 users) | $50 – $150 | Database upgrade, Vercel Pro ($20/mo), PostHog or analytics upgrade, Clerk paid tier. |
| Scaling (10,000 users) | $200 – $500 | Higher-tier plans across the stack. At this point, your app should be generating enough revenue to cover costs comfortably. |
Compare this to hiring a developer (minimum $5,000-10,000 per month) or a traditional agency build ($20,000-100,000 upfront), and the economics of vibe coding become very clear. The stack is designed to let you start for free and pay only when your app has real traction.
Next step: Understand the Code AI Writes — Learn to read React components, database queries, and error messages so you can be a more effective vibe coder.