Choosing Your Startup Tech Stack 2025: Decision Guide

80% of startups regret their initial stack choice. Average migration cost: €100K + 6 months. Here's the framework to choose the right stack from the start.

Decision Framework: 7 Criteria

1. Time-to-Market (Weight 30%)

Question: Which stack delivers fastest?

Factors:

• Available boilerplate (templates)
• Rich ecosystem (libs, packages)
• Learning curve
• Dev availability

Example:

• ✅ Next.js: Vercel templates → deploy in 1h
• ⚠️ Custom React + Node: 2-3 days setup
• ❌ Java Spring: 1-2 weeks setup

2. Talent Pool (Weight 25%)

Question: Easy to hire?

France 2025 Benchmark:

Tech	Available Devs	Avg TJM	Hiring
JavaScript/TypeScript	150K+	€450	✅ Easy
React	100K+	€500	✅ Easy
Next.js	30K+	€550	✅ Medium
Python	80K+	€500	✅ Easy
Node.js	60K+	€480	✅ Easy
Vue.js	40K+	€480	⚠️ Medium
Go	15K+	€600	⚠️ Difficult
Rust	5K+	€700	❌ Very difficult
Elixir	2K+	€800	❌ Nearly impossible

Golden Rule: If <20K devs in France, hiring risk

3. Scalability (Weight 15%)

Question: Holds up to how many users?

Benchmark:

Stack	0-10K users	10K-100K	100K-1M	1M+
Next.js + Vercel	✅	✅	✅	⚠️ Costs
React + Node + AWS	✅	✅	✅	✅
Python Django	✅	✅	⚠️ Optimization	⚠️
Ruby on Rails	✅	⚠️	❌ Slow	❌
PHP Laravel	✅	⚠️	⚠️	❌

Note: 99% of startups will never reach 1M users

4. Cost (Weight 15%)

Total Cost of Ownership Year 1:

Stack	Infra	Devs	Licenses	Total
Next.js (Vercel)	€2.4K	€60K	€0	€62.4K
MERN (AWS)	€6K	€60K	€0	€66K
Python (Railway)	€3.6K	€60K	€0	€63.6K
.NET (Azure)	€8K	€65K	€0	€73K
Enterprise Java	€12K	€70K	€5K	€87K

Winner: Modern open-source stack + PaaS

5. Ecosystem (Weight 10%)

Library Richness:

Stack	Packages	Quality	Docs
JavaScript (npm)	2M+	⚠️ Variable	✅
Python (PyPI)	500K+	✅	✅
Java (Maven)	500K+	✅	✅
Go	100K+	✅	⚠️
Rust	100K+	✅	⚠️

6. Maturity (Weight 3%)

Stability:

Stack	Age	Stability	Breaking Changes
Next.js	8 years	⚠️ v15 = breaking	Annual
React	12 years	✅	Rare
Vue	10 years	✅	v3 = breaking (2020)
Node.js	15 years	✅	Rare
Python	33 years	✅	Rare
Go	15 years	✅	Rare

7. DX (Developer Experience) (Weight 2%)

Development Pleasure:

Stack	Setup	Hot Reload	Debug	Satisfaction
Next.js	🟢 1h	🟢 Fast	🟢	9/10
Vite + React	🟢 30min	🟢 Ultra fast	🟢	9/10
Create React App	🟡 2h	🟡 Slow	🟡	6/10
Django	🟢 1h	🟢	🟢	8/10
Rails	🟡 2h	🟡	🟢	7/10

Recommended Stacks 2025 by Use Case

Use Case 1: B2B SaaS (dashboard, analytics)

Recommended Stack: Next.js 15 + tRPC + PostgreSQL + Vercel

Architecture:

Frontend: Next.js 15 (App Router)
├─ UI: shadcn/ui + Tailwind CSS
├─ State: Zustand
├─ Forms: React Hook Form + Zod
└─ Charts: Recharts

Backend: tRPC API (Next.js /app/api)
├─ ORM: Prisma
├─ Database: PostgreSQL (Supabase)
├─ Auth: NextAuth.js
├─ Payments: Stripe
└─ Jobs: Inngest (background tasks)

Infra: Vercel Edge
├─ CDN: Automatic
├─ Analytics: Vercel Analytics
└─ Monitoring: Sentry

Advantages:

• ✅ Full-stack TypeScript (optimal DX)
• ✅ 1-click deploy
• ✅ SSR + ISR for SEO
• ✅ Vercel Edge = ultra-fast
• ✅ End-to-end type-safety (tRPC)

Disadvantages:

• ❌ Vercel vendor lock-in (complex migration)
• ❌ Costs if >10K users (€300-500/month)

Year 1 Budget: €3K infra + €60K dev = €63K

Setup Time: 2-3 days

Use Case 2: Marketplace (supply + demand)

Recommended Stack: React + Node + MongoDB + AWS

Architecture:

Frontend: React 19 (Vite)
├─ Routing: React Router v7
├─ UI: Material-UI
├─ State: TanStack Query + Context
└─ Forms: Formik

Backend: Node.js + Express
├─ Database: MongoDB (Atlas)
├─ Search: Elasticsearch
├─ Storage: S3
├─ Queue: Bull + Redis
├─ Real-time: Socket.io
└─ Auth: Passport.js

Infra: AWS (EC2 + RDS + S3)
├─ Load balancer: ALB
├─ CDN: CloudFront
└─ Monitoring: CloudWatch + Datadog

Advantages:

• ✅ Flexible schema (MongoDB)
• ✅ Real-time (chat, notifications)
• ✅ Powerful search (Elasticsearch)
• ✅ No vendor lock-in

Disadvantages:

• ❌ Complex setup (DevOps required)
• ❌ AWS costs from start

Year 1 Budget: €8K infra + €70K dev = €78K

Setup Time: 1-2 weeks

Use Case 3: Mobile-first app (iOS + Android)

Recommended Stack: React Native + Expo + Supabase

Architecture:

Mobile: React Native + Expo
├─ Navigation: React Navigation
├─ UI: React Native Paper
├─ State: Zustand
└─ Offline: WatermelonDB

Backend: Supabase (BaaS)
├─ Database: PostgreSQL
├─ Auth: Supabase Auth
├─ Storage: Supabase Storage
├─ Real-time: Supabase Realtime
└─ Edge Functions: Deno

Push: Expo Notifications

Advantages:

• ✅ 1 codebase = iOS + Android
• ✅ Supabase = ready backend
• ✅ OTA updates (Expo)
• ✅ Minimal budget

Disadvantages:

• ❌ Performance < native (3D games impossible)
• ❌ Expo/Supabase dependency

Year 1 Budget: €1.5K infra + €65K dev = €66.5K

Setup Time: 1 week

Use Case 4: E-commerce (physical products)

Recommended Stack: Next.js + Shopify Hydrogen OR Medusa.js

Option A: Shopify Hydrogen (no-code backend)

Architecture:

Frontend: Next.js + Shopify Hydrogen
├─ UI: Tailwind CSS
├─ Cart: Shopify Storefront API
└─ Checkout: Shopify Checkout

Backend: Shopify Admin
├─ Products: Shopify
├─ Orders: Shopify
├─ Inventory: Shopify
└─ Payments: Shopify Payments

Infra: Vercel

Advantages:

• ✅ 0 backend code
• ✅ Payments included
• ✅ Inventory management

Disadvantages:

• ❌ Shopify commission (2% + €0.30/transaction)
• ❌ Strong lock-in

Year 1 Budget: €3K infra + €30K dev = €33K + commissions

Option B: Medusa.js (open-source)

Architecture:

Frontend: Next.js
Backend: Medusa.js (Node.js)
├─ Products: PostgreSQL
├─ Cart: Medusa
├─ Orders: Medusa
└─ Payments: Stripe

Infra: Railway (backend) + Vercel (frontend)

Advantages:

• ✅ 0 commission (vs Shopify)
• ✅ 100% customizable
• ✅ Open-source

Disadvantages:

• ❌ Backend code required
• ❌ Inventory management to build

Year 1 Budget: €5K infra + €50K dev = €55K

Use Case 5: Data-intensive app (analytics, ML)

Recommended Stack: Python FastAPI + PostgreSQL + React

Architecture:

Frontend: React + Vite
├─ Charts: Plotly.js
├─ Tables: TanStack Table
└─ State: Redux Toolkit

Backend: Python FastAPI
├─ ORM: SQLAlchemy
├─ Database: PostgreSQL
├─ ML: scikit-learn / TensorFlow
├─ Data: Pandas / NumPy
└─ Cache: Redis

Infra: Railway (backend) + Vercel (frontend)
├─ Jobs: Celery + Redis
└─ Storage: S3

Advantages:

• ✅ Python = ML ecosystem
• ✅ FastAPI = performant
• ✅ Jupyter notebooks integration

Disadvantages:

• ❌ 2 languages (Python + JS)
• ❌ Manual type-safety

Year 1 Budget: €6K infra + €70K dev = €76K

Setup Time: 1 week

Common Mistakes to Avoid

Mistake #1: Hype Stack Without Reason

❌ Bad:

"We'll do Rust + WebAssembly because it's cool"

Problem:

• Hiring Rust devs = mission impossible
• Time-to-market x3
• Over-engineering

✅ Good:

"We do Next.js + Node because 100K devs available in France"

Mistake #2: Copy BigTech Stack

❌ Bad:

"Netflix uses microservices + Kafka, we'll do the same"

Problem:

• Netflix = 10K engineers, you = 2 devs
• Complexity kills startups

✅ Good:

"Netflix started with Ruby monolith. So do we."

Mistake #3: "Full-stack Developer" Stack

❌ Bad:

"I'll hire a fullstack JavaScript dev, he does everything"

Problem:

• Specialist > generalist
• 1 person = 1 SPOF (Single Point of Failure)

✅ Good:

"Frontend specialist + Backend specialist OR Senior fullstack + Specialized junior"

Mistake #4: Ignoring Hidden Costs

Example:

• AWS = "free" → €5K/month bill after 6 months
• Serverless = "cheap" → Cold starts + scale costs

✅ Calculate TCO (Total Cost of Ownership):

TCO Year 1 =
  Infra costs
  + Developer salaries
  + Licenses (if any)
  + Migration costs (if pivot)
  + Opportunity cost (time-to-market)

Mistake #5: No Plan B (Exit Strategy)

❌ Bad:

"Vercel/Supabase vendor lock-in, we'll see later"

Problem:

• Migration = €100K + 6 months if issue

✅ Good:

"Vercel now, but architecture allows AWS migration if needed"

Strategy:

• Abstract dependencies (e.g., lib/db.ts wraps Prisma)
• Docker containers (portable)
• Infrastructure as Code (Terraform)

Decision Tree: Which Stack for ME?

Questions

Q1: Need SEO?

• Yes → Next.js SSR
• No → React SPA (Vite)

Q2: Mobile app?

• Yes → React Native + Expo
• No → Web responsive

Q3: Real-time (chat, collab)?

• Yes → Node.js + Socket.io OR Supabase Realtime
• No → REST API classic

Q4: Data/ML intensive?

• Yes → Python (FastAPI/Django)
• No → JavaScript/TypeScript

Q5: Limited dev budget (<€50K)?

• Yes → No-code backend (Supabase, Firebase) + Next.js
• No → Custom backend

Q6: Team <3 devs?

• Yes → Fullstack framework (Next.js, Remix)
• No → Microservices OK

Decision Tree Result

Early Startup (0-10 clients): → Next.js + Supabase + Vercel

• Time-to-market: 2-3 weeks
• Budget: €60K Year 1

Scale-up (10-100 clients): → React + Node + PostgreSQL + AWS

• Scalable architecture
• Budget: €80K Year 1

Mobile-first: → React Native + Expo + Supabase

• 1 codebase iOS+Android
• Budget: €65K Year 1

E-commerce: → Next.js + Shopify Hydrogen

• 0 backend code
• Budget: €35K Year 1 + commissions

Data/ML: → Python FastAPI + React + PostgreSQL

• ML ecosystem
• Budget: €75K Year 1

Migration: When to Change Stack?

Signals to Migrate

Red Flags:

• ❌ Impossible to hire (Elixir, Rust)
• ❌ Catastrophic perf (<1s load)
• ❌ Costs explode (x10 vs budget)
• ❌ Unmanageable tech debt (bugs > features)
• ❌ Abandoned technology (AngularJS, Meteor)

If 2+ red flags → Consider migration

Typical Migration Cost

Example: Rails → Next.js + Node

Phase	Duration	Cost
Audit	1 week	€5K
New Stack POC	2 weeks	€10K
Incremental Migration	3-6 months	€60-120K
Bug Buffer	1 month	€10K
TOTAL	4-7 months	€85-145K

ROI:

• Easier hiring (Ruby → JS)
• Perf x5
• Infra costs -40%

Break-even: 12-18 months

Conclusion: My 2025 Recommendation

Universal Startup Early Stack

If you don't know what to choose:

Frontend: Next.js 15 (App Router) + Tailwind CSS + shadcn/ui
Backend: tRPC (colocated with Next.js)
Database: PostgreSQL (Supabase)
Auth: NextAuth.js
Payments: Stripe
Hosting: Vercel
Monitoring: Sentry + Vercel Analytics

Why:

• ✅ Optimal time-to-market (2-3 weeks MVP)
• ✅ Huge talent pool (JS/TS)
• ✅ Scalable (100K users easy)
• ✅ Controlled costs (€3K infra/year)
• ✅ End-to-end type-safe
• ✅ Exit strategy possible (containerize → AWS)

Exceptions:

• Mobile-first → React Native + Expo
• Data/ML → Python FastAPI
• Enterprise → .NET/Java

Tech Stack Audit: Is your current stack adapted? Let's discuss in 30min.

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About: Jérémy Marquer has built 30+ MVPs with 15 different stacks. Recommendation: Next.js 90% of the time.