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

E2B: Pricing, Features & Alternatives

E2B is the sandbox layer many agent products and code-interpreter features call when a model writes code that has to actually run. Each sandbox is an isolated microVM that starts in well under a second, with SDKs for Python and JavaScript and filesystem, process and network access. Compute is billed per second on every plan ($0.000014 per vCPU-second, $0.0000045 per GiB-second). Plans change the limits: Hobby is free with $100 of one-time credit, 1-hour sessions and 20 concurrent sandboxes. Pro is $150/month for 24-hour sessions and 100 concurrent sandboxes, with add-ons up to 1,100. Enterprise starts at $3,000/month and adds bring-your-own-cloud.

E2B Pricing Plans (2026)

Plan	Price	Highlights
Hobby	$0 + $100 one-time usage credit	Sessions up to 1 hour · 20 concurrent sandboxes · $0.000014 / vCPU-second
ProPopular	$150 / month + usage	Sessions up to 24 hours · 100 concurrent sandboxes · Add-ons to 600 or 1,100 concurrent
Enterprise	From $3,000 / month	BYOC and custom deployment · Custom concurrency and limits

Pricing summary: Free · paid from $150/mo. Always confirm current pricing on the official site.

Key E2B Features

Sessions up to 24 hours
100 concurrent sandboxes
Add-ons to 600 or 1,100 concurrent

Pros

+Purpose-built for agents, with SDKs designed around tool calls
+Fast microVM startup with real isolation
+Open-source core

Cons

−$150/month before any compute on the first paid tier
−Hobby sessions cap at one hour
−Usage billing on top of the plan makes costs harder to forecast

Best E2B Alternatives

Compare all

Modal

Free · paid from $250/mo

Vercel Sandbox

Free · then usage-based

E2B Compared

E2B vs Modal E2B vs Vercel Sandbox

E2B FAQ

What is E2B used for?⌄

E2B is a agent sandboxes & code execution tool. Open-source cloud sandboxes built for AI agents to run code in. The Hobby tier is free with $100 in credits, and Pro is $150/month plus usage.

Is E2B free?⌄

Yes — E2B has a free tier you can start with, and paid plans for more usage and features.

How much does E2B cost?⌄

E2B offers a free tier, with paid plans starting at $150/month. Some plans are usage-based (pay-as-you-go).

What are the best E2B alternatives?⌄

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

Not sure if E2B fits your stack?

Get a free, AI-powered tech stack tailored to your budget, app type, and team size — including the best agent sandboxes & code execution pick for you.

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