The Modern SaaS Tech Stack I'd Choose in 2025

Every week, founders ask me: "What tech stack should we use for our SaaS?" After building 50+ products and seeing what actually works in production, here's my 2025 recommendation.

The winning teams I work with treat their stack like a go-to-market decision: it has to remove friction for engineers, keep compliance happy, and give product a predictable runway. When we step in as a fractional CTO partner, the mandate is always the same: ship more value with less ceremony, not chase the shiny object of the month.

The Non-Negotiable Principles

Before diving into specific technologies, understand these principles:

• Boring is beautiful - Proven tech > bleeding edge
• Developer velocity matters - Fast iteration > perfect architecture
• Scale when you need to - Don't optimize for 1M users at 100 users
• Full-stack TypeScript - One language, less context switching

Break any of those rules and the hidden costs show up instantly. Last summer I inherited a React + Laravel mashup that took four engineers to deploy because every change tripped over hand-rolled auth and duplicated types. We replaced it with the stack below and cut deploy time from five hours to fifteen minutes without writing a single new feature.

The Core Stack

Frontend - Next.js 14+ with App Router

Why: Next.js has become the de facto standard for React applications with good reason:

• Server Components reduce client bundle size by 30-40%
• Built-in image optimization and font loading
• Edge runtime support for global performance
• Streaming and partial pre-rendering

Alternative considered: Remix (great option, but smaller ecosystem)

UI Components - shadcn/ui + Tailwind CSS

Why: This combination gives you:

• Copy-paste components you own and can modify
• Consistent design system out of the box
• Accessibility built-in with Radix UI
• 60% faster development than custom components

What we use:

// Beautiful, accessible components in minutes
import { Button } from '@/components/ui/button'
import { Card } from '@/components/ui/card'
import { Dialog } from '@/components/ui/dialog'

Backend API - tRPC or Next.js Route Handlers

For most SaaS: Next.js Route Handlers are sufficient When you need more: tRPC for type-safe APIs

Why Route Handlers for most cases:

• No additional complexity
• Works with any frontend
• Easy to add authentication
• Simple to test and debug

Database - PostgreSQL with Prisma

Why PostgreSQL:

• Battle-tested for 30+ years
• Handles 99% of SaaS use cases
• Amazing extensions (pgvector for AI, PostGIS for location)
• Scales from 0 to Notion-size

Why Prisma:

• Type-safe database queries
• Automatic migrations
• Great developer experience
• Works with edge runtimes

Authentication - Clerk or NextAuth.js

For speed: Clerk (5 minutes to production-ready auth) For control: NextAuth.js (more configuration, more flexibility)

What Clerk gives you:

• Social logins
• Multi-factor authentication
• User management UI
• Webhooks for user events
• SOC 2 compliance out of the box

Hosting - Vercel + Neon

Why this combination:

• Vercel: Zero-config deployments, automatic scaling
• Neon: Serverless Postgres with branching for development
• Total cost at 10k MAU: ~$50/month

Alternative: Railway or Render for everything (simpler, one vendor)

The AI Layer (Because It's 2025)

LLM Integration - Vercel AI SDK

import { openai } from '@ai-sdk/openai'
import { generateText } from 'ai'

const { text } = await generateText({
  model: openai('gpt-4-turbo'),
  prompt: 'Generate a product description',
})

Vector Database - pgvector

No need for a separate vector database. PostgreSQL with pgvector handles:

• Semantic search
• RAG implementations
• Recommendation systems

AI Development - Cursor + Claude

This isn't part of your stack, but it's how you build faster:

• 60% reduction in boilerplate code time
• Instant refactoring across files
• Better error messages and debugging

The Payment Stack

Payments - Stripe

Still unmatched for:

• Developer experience
• Global coverage
• Subscription management
• Revenue recognition

Alternative - Paddle (if you want to avoid tax compliance headaches)

The Observability Stack

Analytics - PostHog

One tool for:

• Product analytics
• Session recordings
• Feature flags
• A/B testing
• Error tracking

Monitoring - Vercel Analytics + Sentry

• Vercel Analytics: Web vitals and performance
• Sentry: Error tracking and performance monitoring

The Communication Stack

Transactional Email - Resend

await resend.emails.send({
  from: 'onboarding@example.com',
  to: user.email,
  subject: 'Welcome to SaaS!',
  react: WelcomeEmail({ name: user.name }),
})

Marketing Email - ConvertKit or Loops

ConvertKit for creator-focused products with advanced automation needs. Loops for modern SaaS with a cleaner UI and better developer experience. Both handle compliance and deliverability so you don't have to.

In-app notifications - Knock or build your own

Knock gives you a complete notification system in minutes - in-app, email, SMS, and push. Building your own is feasible for simple needs but gets complex fast when you add preferences, batching, and delivery tracking.

Real-World Stack Wins

BizJetJobs: 2.5× MRR by simplifying the core

BizJetJobs approached us with a decade-old WordPress build that chained together eight plugins and a fragile PHP API. We rebuilt the platform with this stack: Next.js on Vercel, Prisma on top of Neon, and shadcn/ui for reusable components, while introducing feature flags and proper analytics.

• Reporting moved from weekly CSV exports to live dashboards backed by PostHog and Vercel Analytics.
• Automated onboarding flows and billing webhooks cut support requests by 60%.
• A shared TypeScript schema finally aligned product, engineering, and growth teams on a single source of truth.

"Matthew's vision and code turned our WordPress site into the revenue engine that fuels 10 years of YoY growth." - Meredith Koubsky, Co-founder, BizJetJobs

Ready to see the full story? Explore the BizJetJobs case study to understand how these stack choices translated into 2.5x MRR.

StaySignal: Cancellation intelligence on the same playbook

StaySignal needed an embedded cancellation experience that captured feedback, delivered retention offers, and surfaced churn analytics in real time. We bootstrapped the product with this exact stack: Next.js 14, Supabase, Stripe, and Vercel so the founder could plug the widget into live SaaS environments quickly.

• The cancellation widget, multi-step feedback flow, and retention offer engine shipped quickly because Supabase and Stripe integrations were part of the base template.
• Shared TypeScript models across widget, dashboard, and API routes kept customer context and incentives aligned.
• Preview branches let us validate cancellations end-to-end before rolling the experience out to production tenants.

"What started as a simple MVP turned into something much more complete and impressive thanks to his dedication and skill." - Tom van den Heuvel, Founder, StaySignal

The same patterns power our StaySignal case study, which covers the embedded cancellation experience, retention automations, and analytics we delivered.

The Testing Stack

Unit/Integration - Vitest

Faster than Jest, with native TypeScript support and compatibility with your existing test suite. Runs tests 10x faster with better error messages.

E2E - Playwright

Microsoft's answer to Cypress, but better. Cross-browser testing that actually works, with auto-wait capabilities and parallel execution out of the box.

Visual Regression - Percy (optional)

Catch unexpected UI changes before your users do. Integrates with your CI pipeline to screenshot every deployment and highlight visual differences.

The Development Workflow

Version Control - GitHub

Still the industry standard. Great Actions integration, Copilot AI assistance, and where all the open source lives. GitLab is fine too, but why swim upstream?

CI/CD - GitHub Actions + Vercel

Push to main, deploy to production. Vercel's preview deployments for every PR mean stakeholders can review changes before they ship. No more "works on my machine" problems.

Code Quality - ESLint + Prettier + Husky

Enforce consistent code style automatically. Husky runs checks before commits, preventing broken code from entering your repository. Set it up once, never think about formatting again.

What I Deliberately Leave Out

GraphQL

Unless you have multiple frontends consuming the same API, it's complexity you don't need.

Microservices

Start with a monolith. You're not Netflix.

Kubernetes

You don't need container orchestration below $1M ARR.

Redis

PostgreSQL can handle caching for most use cases.

Separate API Server

Next.js API routes scale to millions of requests.

Cost Breakdown at Different Stages

MVP Stage (0-100 users)

• Total: $0-20/month
• Vercel free tier
• Neon free tier
• Clerk free tier

Growth Stage (100-1,000 users)

• Total: $50-150/month
• Vercel Pro: $20
• Neon: $20
• Clerk: $25
• PostHog: $0 (free tier)

Scale Stage (1,000-10,000 users)

• Total: $300-800/month
• Vercel Pro: $20
• Neon Pro: $70
• Clerk: $250
• PostHog: $200
• Others: $100-200

Migration Path

As you scale, your needs change. Here's the typical evolution:

• Year 1: Stack as described above
• Year 2: Add Redis for caching, consider dedicated backend
• Year 3: Evaluate microservices for specific domains
• Year 4+: Custom solutions where needed

The Decision Framework

Choose this stack when:

• ✅ Building B2B SaaS
• ✅ Team knows React/TypeScript
• ✅ Need to move fast
• ✅ Want proven, boring technology
• ✅ Planning for under 100k users initially

Consider alternatives when:

• ❌ Building consumer social apps (consider React Native)
• ❌ Heavy real-time requirements (add Socket-io or consider Elixir)
• ❌ Complex computational needs (add Python services)
• ❌ Team expertise in other stacks

FAQ

How flexible is this stack if my team prefers different tools?

Use stack swaps sparingly. Keep Next.js, TypeScript, and Postgres as the backbone, then trade peripheral services (Clerk for Auth0, Resend for Postmark, etc.) when compliance or legacy reasons demand it. That way you avoid fragmenting your language, deployment pipeline, or developer onboarding.

When do we actually need microservices or Kubernetes?

Stay inside a well-factored monolith until coordination truly hurts: multiple teams shipping weekly, strict data isolation, or scale that needs independent deploys. Most B2B SaaS products can comfortably ride this stack past $1M ARR with feature flags and strong testing before the operational overhead of microservices makes sense.

Is Neon or other serverless Postgres ready for production SaaS?

Yes, as long as you treat it like any production database: enable nightly backups, monitor connection limits, and upgrade long-lived branches to dedicated instances once write volume spikes. Several Continuum clients run Neon in production with predictable latency and painless branching for QA.

How do AI workloads fit into this setup without blowing up costs?

Lean on the Vercel AI SDK for orchestration, meter requests with usage caps, and cache expensive responses in Postgres when you can. That lets you experiment with models before committing to higher-tier plans and keeps infrastructure simple until you prove demand.

How fast can a fractional CTO stand up this stack?

With decision frameworks ready, we usually ship the baseline platform (auth, database, CI/CD, analytics) in two sprints. Week three adds AI and payments. The real bottleneck is alignment, which is why we front-load workshops to lock scope before code starts flying.

Conclusion

The best tech stack is the one that lets you ship features quickly while maintaining code quality. This stack has been battle-tested across dozens of successful SaaS products and consistently delivers.

Remember: your tech stack is a means to an end. The goal is to build something customers love, not to have the most sophisticated architecture.

Want hands-on help implementing it? Explore our SaaS development agency service for the end-to-end buildout, or pair the strategy with ongoing leadership through the virtual CTO engagement.

Next Steps

• Start with the basics: Next.js + PostgreSQL + Tailwind
• Add complexity as needed: Don't prematurely optimize
• Measure and iterate: Use analytics to guide decisions
• Get help when needed: Consider fractional CTO support

Need help choosing or implementing your tech stack? Book a quick-win audit for personalized recommendations based on your specific needs.