What is App Stack Builder?

App Stack Builder is a free AI-powered tool that helps founders and developers choose the right tech stack for their projects based on budget, app type, team size, and skill level.

What is the best tech stack for SaaS in 2026?

The best tech stack for SaaS in 2026 typically includes Next.js 16 for frontend, Supabase for database and auth, Vercel for hosting, Stripe for payments, and PostHog for analytics. App Stack Builder can generate a personalized recommendation based on your specific budget and requirements.

Is App Stack Builder free to use?

Yes, App Stack Builder is completely free to use. You can generate unlimited tech stack recommendations without any cost.

What types of apps can I build with the recommended stacks?

App Stack Builder supports various app types including SaaS applications, web apps, mobile apps, e-commerce stores, internal tools, and AI/ML products.

How much does a SaaS tech stack cost per month?

A modern SaaS tech stack can cost anywhere from $0-50/month for bootstrapped startups using free tiers, $100-300/month for growth-stage startups, to $500+/month for enterprise-ready infrastructure. App Stack Builder helps you find the best tools within your specific budget.

What is the best tech stack for solo founders?

For solo founders, we recommend Next.js + Vercel (free), Supabase (free tier), Supabase Auth (free), Stripe (pay as you go), and Plausible or PostHog for analytics. This stack can run your entire SaaS for under $50/month.

Can I export my tech stack recommendations?

Yes, you can export your tech stack recommendations as a PDF document or copy them to your clipboard. You can also share a link to your stack with others.

Auth

Clerk vs NextAuth.js: Which is Better in 2026?

Name: App Stack Builder
Availability: InStock

Choosing between Clerk and NextAuth.js? Both are popular auth tools. Below we compare them on pricing, free tiers, features, and pros & cons so you can pick the right fit for your stack.

Quick verdict

Both Clerk and NextAuth.js are strong auth choices. The right pick comes down to your specific feature needs, existing stack, and team preferences.

Clerk vs NextAuth.js — Side by Side

	Clerk	NextAuth.js
Category	Auth	Auth
Pricing	Free · paid from $25/mo	Free
Starting price	Free tier available	Free tier available
Free tier
Best for	Auth — authentication, authorization	Auth — authentication, nextjs

Pros & Cons

Clerk

Excellent developer experience
Prebuilt auth UI saves time
Strong Next.js and React integration
Handles organizations and roles well

Pricing scales with MAUs
Vendor lock-in for auth flows
Less flexible for highly custom auth logic

NextAuth.js

Completely free and open source
Deep integration with Next.js
No vendor lock-in
Highly customizable auth flows
Strong security defaults

Requires backend setup and maintenance
No built-in admin dashboard
Not beginner-friendly compared to hosted auth services

Choose Clerk if…

you want a free tier to start, and Clerk Complete authentication and user management platform for modern web applications.

Clerk review & pricing

Choose NextAuth.js if…

you want a free tier to start, and NextAuth.js Open-source authentication solution for Next.js with built-in providers, sessions, and security best practices.

NextAuth.js review & pricing

Frequently Asked Questions

Is Clerk better than NextAuth.js?⌄

Both Clerk and NextAuth.js are strong auth choices. The right pick comes down to your specific feature needs, existing stack, and team preferences.

What is the difference between Clerk and NextAuth.js?⌄

Clerk — Complete authentication and user management platform for modern web applications. NextAuth.js — Open-source authentication solution for Next.js with built-in providers, sessions, and security best practices. Both are auth tools; the comparison table above breaks down pricing, free tiers, and what each is best for.

Clerk vs NextAuth.js: which is cheaper?⌄

Clerk pricing: Free · paid from $25/mo. NextAuth.js pricing: Free. Confirm current pricing on each tool's official site, as plans change.

See more options in our guide to the best auth tools for startups.

Still not sure which to pick?

Get a free, AI-powered tech stack — including the best auth pick for your budget and team — in 60 seconds.

Build my stack free