One default for every layer a startup needs, from the frontend to payments and AI, with what each costs, when to pick the alternative, and the open source option.
One catch to check first: Vercel’s free Hobby plan is for personal projects. A product that takes payments needs Pro.
Prices and the “pick it when” notes come from our side by side comparisons, which are checked against each provider’s public pricing page. Follow any comparison for the full feature table.
One TypeScript codebase for the marketing site and the product, server rendering for search, and components you own. Every AI builder and most tutorials assume this combination.
Free and open source
Push to deploy with previews for every branch, made by the team behind Next.js. Watch the plan terms: the free Hobby plan is for personal projects, so a commercial product belongs on Pro.
Vercel Pro at $20/user is standard. Netlify Pro at $19/user is virtually identical. Bandwidth overages are where surprises land, both cost ~$40/100 GB extra.
Building with Next.js, need edge functions, want preview URLs per commit, or care about the tightest DX for React.
Multiframework studio, need Netlify Forms or built in split testing, prefer predictable pricing, or shipping a mostly static marketing site.
Real Postgres with auth, storage and realtime around it. You get a backend in an afternoon and plain SQL underneath, so leaving later is a migration, not a rewrite.
Public pricing pages, verified 27 Jul 2026. Firebase can be cheaper at low volume but harder to predict at scale, model your reads/writes carefully before committing.
Web first app, needs relational queries, wants portability, or has a founder comfortable with SQL and row level security policies.
Mobile first app (especially Flutter or native), needs push notifications and Crashlytics out of the box, or values Google's global infra over open source.
If you are on Supabase its auth is already included. Clerk earns its fee when you want polished sign in screens and team accounts without building them.
If you already pay for Supabase Pro, Supabase Auth is effectively free. Clerk adds ~$25/mo but saves you time building UI and org flows.
You already use Supabase for your DB, want auth to be free forever, and are OK building your own sign in / profile UI (or using the Supabase UI library).
You want the fastest possible auth setup, need built in orgs + roles + invitations + impersonation, and don't mind paying $25/mo once you scale.
Stripe has the lowest headline rate and the widest ecosystem. Paddle acts as the merchant of record and handles tax for you, which is worth its higher fee for a solo founder selling worldwide.
Public pricing pages, verified Aug 2026. Stripe's advertised rate looks cheaper until you add Stripe Tax and the operational cost of managing tax registrations yourself, at that point the gap to Paddle narrows considerably for a global SaaS.
You want full control over checkout and billing logic, you are comfortable handling sales tax and VAT yourself (or paying separately for Stripe Tax), or you already depend on Stripe specific integrations.
You are a solo founder or small team selling a SaaS product globally and do not want to think about VAT registrations, or you want one predictable rate instead of assembling tax compliance yourself.
A clean API, React email templates and a free tier you can actually launch on.
Pricing is virtually identical at the same volume. Resend often feels cheaper because its free tier is genuinely usable (3000/mo vs 100/day).
You are shipping a new app, want React Email templates, need a clean API and dashboard, and expect to send under a few million emails a month.
You have millions of emails per month, need deep analytics + suppression lists, need marketing + transactional in one tool, or you are already in the Twilio ecosystem.
Analytics, session replay, feature flags and experiments from one SDK, with a free tier that covers most early products.
Public pricing pages, verified Aug 2026. Both are usage based past their free tier, model your expected event or user volume before picking, the two free tiers are shaped differently enough that the cheaper option depends entirely on your product's usage pattern.
You want analytics, session replay, feature flags, and experimentation in one place without integrating separate vendors, or you want the option to self host for data control.
You specifically need best in class funnel and retention analysis, your team is used to Mixpanel already, or you would rather pick specialized tools for replay and flags separately.
Errors grouped by release with the stack trace and the user affected, so you hear about a bug before the support email.
Free tier for small teams, then usage based
A typed SDK for streaming and tool calls, one gateway to cap spend and fall back between providers, and a model chosen on your prompts rather than its launch post.
Depends on the model. See the cheapest LLM API ranking
If you started on an AI builder or a platform, the stack above still applies underneath. The launch checklist for your starting point lists what that tool leaves for you to finish.
Microservices, Kubernetes and a separate search cluster slow a three person team down. One app, one Postgres database and managed hosting go a very long way.
Proprietary query models make the first migration a rewrite. Postgres, through Supabase or Neon, keeps every exit open.
Sign in, password resets, webhooks and tax are where small teams get breached or fined. Use the managed option until you have a reason not to.
Without error tracking and product analytics you learn about bugs from churn. Both have free tiers; install them before launch day.
For most web products: frontend, Next.js, Tailwind CSS and shadcn/ui; hosting, Vercel; database and backend, Supabase; authentication, Supabase Auth, or Clerk for prebuilt UI and organisations; payments, Stripe, or Paddle if you sell globally and do not want to handle sales tax; email, Resend; product analytics, PostHog; error monitoring, Sentry; ai features, The AI SDK, a gateway such as LiteLLM, and the cheapest model that passes your evals. It is one language end to end, every layer has a usable free tier, and none of the choices locks you in.
Close to nothing before launch, because every layer here has a free tier. Once you charge customers, budget for a hosting plan that allows commercial use, a paid database tier and usage based email, analytics and payments fees. Each layer below shows the provider prices we have verified.
For a first prototype, often yes. They generate a working Next.js or Vite app quickly. Before real users arrive, export the code to your own repo and check the parts builders skip: auth rules, secrets, rate limits and payment webhooks. The Stack Grader checks exactly those.
Supabase for most web products, because it is real Postgres you can leave. Firebase for mobile first apps that want push notifications and Crashlytics built in. The full comparison has the feature and pricing detail.
No. A startup with fewer than twenty engineers is almost always faster on one app, one database and managed hosting. Split services when a real bottleneck forces it, not before.
Start with an AI app builder on the same foundations (Next.js and Supabase), so a developer you hire later can take the code over. Then run the launch checklist for that builder before you charge anyone.
Ten plain English questions on auth, secrets, backups, rate limits and payments. A letter grade and a fix plan ranked by impact, in about three minutes.
Grade my stack