Building a SaaS in 2026 with open-source tools is faster, cheaper, and more portable than any time in history. You can ship a production SaaS in a weekend if you pick the right stack.
This guide is the curated version — not "100 ways to do it" but "here's exactly what to use and why."
The complete stack (TL;DR)
| Layer | Pick | Why |
|---|---|---|
| Frontend framework | Next.js 15 | Server Components, App Router, edge runtime — best DX |
| UI components | shadcn/ui + Tailwind | Own the code, ship custom designs |
| Animation | Motion (Framer Motion) | React-first, declarative |
| Backend | Supabase | Postgres + Auth + Storage + Edge functions in one platform |
| Auth | Better Auth | Modern, typesafe, framework-agnostic |
| Payments | Razorpay (India) / Stripe (global) | Local payment methods matter |
| Resend + react-email | Modern, deliverable, dev-friendly | |
| AI | Vercel AI SDK + Ollama | Streaming UI + local dev |
| Analytics | Plausible (privacy-first) | GDPR-safe, simple |
| Hosting | Vercel or Railway | Both work, Railway cheaper for full-stack |
| Domain | Namecheap / Porkbun | Avoid registrars with poor support |
| Monitoring | Sentry (free tier) | Error tracking is non-optional |
This is the exact stack StackPicks itself runs on. We chose every piece by living with the alternatives.
1. Frontend — Next.js 15 + shadcn/ui
Next.js 15 is the right default in 2026. Server Components reduce client JS by 60-80%. The App Router is finally stable. Vercel and Railway both support it natively.
Build with **shadcn/ui** for components. You copy the code into your project — no npm dependency to break in 6 months. Backed by Radix primitives so accessibility is correct out of the box.
For complete UI library tradeoffs, see **Best Open-Source UI Libraries 2026**.
**Animation layer:** Motion (Framer Motion). React-first. Use for page transitions, micro-interactions, scroll reveals.
2. Backend — Supabase
Supabase is the right default in 2026 for solo founders and small teams. You get:
- Postgres (the right database for 95% of SaaS use cases)
- Auth (Email + OAuth providers + Magic links)
- Storage (S3-compatible file storage)
- Edge Functions (Deno-based, for serverless work)
- Row-Level Security baked in — *every public table must have RLS*
The Mumbai region (ap-south-1) is essential for India-first products. Indian users get sub-100ms latency.
RLS is the killer feature. Every public table gets policies like auth.uid() = user_id that enforce access at the database level. Your client-side code can't bypass it. This is what makes Supabase safe for production SaaS without writing a separate backend.
3. Auth — Better Auth (or Supabase Auth)
If you're on Supabase, just use Supabase Auth. Done.
If you're not, **Better Auth** is the modern pick in 2026. Typesafe, framework-agnostic, simpler mental model than NextAuth.
For self-hosted enterprise SSO with SAML/LDAP, you want Keycloak. Heavy but feature-complete.
4. Payments — Razorpay (India) or Stripe (global)
If you're targeting India: Razorpay is the only sane choice. UPI, NetBanking, all major cards, subscription support, and competitive fees (~2% domestic, ~3% international).
We use Razorpay live mode on StackPicks. Their Standard Checkout integration is one HTTP call to create the order, one HMAC verify on success. See our /api/checkout/lifetime source for reference patterns.
If you're targeting US/EU: Stripe. Same simplicity, broader card support, better fraud detection.
Webhook signing is mandatory. Verify every webhook signature server-side before mutating data. If you skip this, anyone can fake a payment.
5. AI integration — Vercel AI SDK + Ollama
For LLM-powered features:
- **Production**: Anthropic Claude or OpenAI GPT-4o via the **Vercel AI SDK**. Streaming responses, structured outputs, tool calling — all in one library.
- **Development**: **Ollama** running Llama 3.3 or Qwen 2.5 locally. Iterate without burning API tokens.
For agents (multi-step LLM workflows), see **Open-Source AI Agent Frameworks Compared**.
6. Email — Resend + react-email
Resend for transactional email. react-email for templates you write in JSX.
Free tier covers 3,000 emails/month — enough for any pre-revenue SaaS.
7. Analytics — Plausible (or Umami)
Plausible is paid but privacy-respecting (no cookies, GDPR-safe). Umami is the open-source self-hosted alternative.
Avoid Google Analytics for new SaaS. The cookie banner alone kills your conversion rate. Plausible has zero cookies.
8. Hosting — Vercel or Railway
Vercel if you're Next.js-first and don't need long-running backend processes. Free tier is generous.
Railway if you have any long-running work (workers, cron, websockets). Pay-as-you-go. We host StackPicks on Railway.
Don't pick AWS / GCP as a solo founder. The ops overhead will kill you. Manage to PMF first, migrate to AWS later if needed.
9. Monitoring — Sentry
Sentry free tier covers 5k errors/month. Sentry's source-map upload + session replay are non-optional for serious products.
Total monthly cost — pre-revenue solo founder
| Service | Cost |
|---|---|
| Supabase Pro | $25/mo (free tier works to ~1k users) |
| Vercel/Railway | $0-20/mo |
| Domain | $10/year |
| Resend | $0 (free tier) |
| Plausible | $9/mo |
| Sentry | $0 (free tier) |
| Total | ~$35/mo |
You can be at $35/mo until ~$1k MRR. After that, costs scale linearly. This is the dream of 2026 — building a real SaaS for less than a Netflix subscription.
What NOT to use in 2026
- MongoDB — Postgres won. Use it.
- Firebase — vendor lock-in to Google, NoSQL only. Pick Supabase instead.
- Redux — Use Zustand or just React state. Redux is over-engineered for 99% of apps.
- GraphQL — Use tRPC or REST. GraphQL has costs that exceed its benefits for solo founders.
- Webpack — Vite or Turbopack. Webpack is a legacy choice.
- Mocha + Chai — Vitest. Done.
The full ship-a-SaaS bundle
We curated the complete stack at **Ship a SaaS bundle** — every repo, every dependency, every config, ready for your AI agent to scaffold.
40+ curated repos. Specific "use this if / skip if" takes. Ready to copy-paste into Cursor or Claude Code.