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.

Payment Gateway

Best Payment Processors for SaaS in 2026

Getting paid shouldn’t be the hard part. From developer-first APIs to merchant-of-record platforms that handle global tax, here are the best payment tools for startups in 2026.

Payment Gateway Tools Compared

Tool	Pricing	Free tier
Polar	Free · paid from $20/mo
Razorpay	Free
Chargebee	Free
Square	Free · paid from $49/mo
Lemon Squeezy	Usage-based	—
Paddle	Usage-based	—
PayPal / Braintree	Usage-based	—
Stripe	Usage-based	—

The Best Payment Gateway Tools, Ranked

1. Polar

Free tier· Free · paid from $20/mo

Developer-first merchant of record for SaaS and digital products — handles global tax, billing, and entitlements.

Merchant of record (offloads tax/VAT)
Great developer experience
Built for SaaS & digital goods

Polar & alternatives

2. Razorpay

Free tier· Free

Leading Indian payment gateway for accepting payments online — UPI, cards, wallets, and subscriptions.

Best-in-class for India/UPI
No monthly fee
Rich payment methods

Razorpay & alternatives

3. Chargebee

Free tier· Free

Subscription billing and revenue management on top of your payment gateway — free up to $250K billed.

Powerful subscription/revenue ops
Generous free starter tier
Integrates with major gateways

Chargebee & alternatives

4. Square

Free tier· Free · paid from $49/mo

All-in-one payments for in-person and online — POS hardware, invoicing, and a free plan.

Great for in-person + online
No monthly base fee
Hardware ecosystem

Square & alternatives

5. Lemon Squeezy

· Usage-based

All-in-one platform for selling digital products with payments, tax compliance, and email marketing.

Lemon Squeezy & alternatives

6. Paddle

· Usage-based

All-in-one payments, billing, and tax compliance platform for SaaS businesses.

Paddle & alternatives

7. PayPal / Braintree

· Usage-based

Global payments platform supporting PayPal, cards, wallets, and local payment methods.

PayPal / Braintree & alternatives

8. Stripe

· Usage-based

Payments infrastructure for the internet with global card support and developer-friendly APIs.

Stripe & alternatives

How to choose a payment gateway tool

Use Stripe for maximum flexibility and the best developer experience.
Pick a merchant of record (Paddle, Lemon Squeezy) to offload global sales tax and VAT.
Compare per-transaction fees against the value of tax/compliance handling.
Check payout countries and supported payment methods for your market.

Frequently Asked Questions

What are the best payment gateway tools for startups in 2026?⌄

The best payment gateway tools for startups in 2026 include Polar, Razorpay, Chargebee, Square, Lemon Squeezy. Compare them by pricing, free tiers, and features in the list above.

What is the best free payment gateway tool?⌄

Free payment gateway options include Polar, Razorpay, Chargebee, Square — all offer a free tier suitable for bootstrapped startups and MVPs.

How do I choose a payment gateway tool?⌄

Start with your budget and team size, prefer tools with a free tier to validate, and make sure your pick integrates with the rest of your stack. App Stack Builder can recommend a complete, budget-aware stack in about 60 seconds.

Need the whole stack, not just payment gateway?

Get a free, AI-powered tech stack — matched to your budget, app type, and team size in 60 seconds.

Build my stack free