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.

Agent Sandboxes & Code ExecutionFree tier

Vercel Sandbox: Pricing, Features & Alternatives

Vercel Sandbox runs each session in an isolated Firecracker microVM, in 19 regions, with up to 8 vCPUs and 24-hour sessions on Pro. Its pricing suits agents well. Active CPU is billed only while code is actually executing ($0.128/hour); time spent waiting on an LLM call does not count. Memory is billed as provisioned ($0.0212/GB-hour), and downloads such as npm installs are free. Hobby includes 5 CPU-hours, 420 GB-hours and 5,000 creations a month, with 45-minute sessions and 10 concurrent sandboxes. On Pro, usage draws down the plan's $20 monthly credit first, and concurrency rises to 10,000.

Vercel Sandbox Pricing Plans (2026)

Plan	Price	Highlights
Hobby	$0 (included quota)	5 active CPU-hours / month · 420 GB-hours memory · 45-minute sessions
ProPopular	Usage-based: $0.128 / active CPU-hour	$0.0212 / GB-hour memory · Uses the Pro plan’s $20 credit first · 24-hour sessions

Pricing summary: Free · then usage-based. Always confirm current pricing on the official site.

Key Vercel Sandbox Features

$0.0212 / GB-hour memory
Uses the Pro plan’s $20 credit first
24-hour sessions
10,000 concurrent sandboxes

Pros

+Active-CPU billing: idle time waiting on the model is free
+Firecracker isolation with snapshots and persistent drives
+Natural fit if the app already runs on Vercel

Cons

−Requires a Vercel account, and Pro for serious use
−Max 8 vCPUs / 16 GB below Enterprise
−Many metered dimensions to model

Best Vercel Sandbox Alternatives

Compare all

Modal

Free · paid from $250/mo

E2B

Free · paid from $150/mo

Vercel Sandbox Compared

Vercel Sandbox vs Modal Vercel Sandbox vs E2B

Vercel Sandbox FAQ

What is Vercel Sandbox used for?⌄

Vercel Sandbox is a agent sandboxes & code execution tool. Firecracker microVMs on Vercel for running untrusted and AI-generated code. You pay only for active CPU time, not for the time a sandbox spends waiting on the model.

Is Vercel Sandbox free?⌄

Yes — Vercel Sandbox has a free tier you can start with, and paid plans for more usage and features.

How much does Vercel Sandbox cost?⌄

Vercel Sandbox is free to use, with usage-based pricing on some features.

What are the best Vercel Sandbox alternatives?⌄

Popular Vercel Sandbox alternatives include Modal, E2B. Compare pricing and features on our Vercel Sandbox alternatives page.

Not sure if Vercel Sandbox fits your stack?

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