MVP in 15 Days: The Complete Guide for Fast-Moving Startups

Do you have a startup idea and want to validate your market quickly? The 15-day MVP (Minimum Viable Product) is the solution. Here’s my proven methodology from 20+ projects.

Why 15 Days?

The 3 Advantages of a Short Sprint

1. Rapid Validation: Test your idea before investing 6 months
2. Controlled Budget: €5K-15K vs €50K+ for a full project
3. Time-to-Market: Get ahead of your competitors

"A delivered MVP is better than a perfect product never launched."

The 3-Phase Methodology

Phase 1: Scoping (Day 1-3)

Goal: Define the minimum viable scope

Scoping Workshop (4h)

• Identify the 3 core features
• Define priority user stories
• Validate success criteria

Deliverables by Day 3

• ✅ Prioritized backlog
• ✅ Low-fi wireframes
• ✅ Validated technical architecture

Phase 2: Development (Day 4-12)

Recommended Stack:

• Frontend: Next.js 15 + React 19 + Tailwind CSS
• Backend: Next.js API Routes or Node.js
• Database: PostgreSQL (Supabase) or MongoDB
• Auth: NextAuth.js or Clerk
• Hosting: Vercel or Railway

3-Day Sprints

Sprint 1 (D4-D6): Setup + Auth + Landing
Sprint 2 (D7-D9): Feature 1 + Feature 2
Sprint 3 (D10-D12): Feature 3 + Polish

Daily Rituals

• 15min daily standup (9:30am)
• End-of-sprint demo
• Real-time adjustments

Phase 3: Deployment (Day 13-15)

Launch Checklist:

• User tests with 5 early adopters
• Fix blocking bugs
• Go live
• Monitoring and analytics in place
• SEO landing page
• Tracking scripts configured

What’s INCLUDED in the MVP

✅ Essential Features

1. Authentication: Login/signup with email or OAuth
2. User Dashboard: Personalized overview
3. Core Feature 1: The feature delivering 80% of the value
4. Core Feature 2: The differentiator vs competitors
5. Core Feature 3: The retention element

✅ Technical Aspects

• Mobile-first responsive design
• Optimized performance (Lighthouse 90+)
• Basic SEO (meta tags, sitemap)
• Analytics (Google Analytics or Plausible)
• Error monitoring (Sentry)
• SSL and basic security

What’s EXCLUDED from the MVP

❌ For v2

• Multi-language (unless core business)
• Advanced personalization
• Push notifications
• Complex integrations
• Full admin dashboard
• Data export
• Public API
• Full automated tests

Budget & Resources

Price Range

Profile	Rate	15-Day Budget
Junior Freelancer	€300-400/day	€4.5K-6K
Senior Freelancer	€500-700/day	€7.5K-10.5K
CTO Freelancer	€800-1200/day	€12K-18K

My positioning: €890/day = €13.5K for a complete MVP with:

• Scoping + wireframes
• Fullstack development
• Deployment + training
• 1 month post-launch support

Savings vs Agency

An agency will charge €30K-50K for the same result with:

• More process/bureaucracy
• Slower response times
• Less flexibility

Example MVPs Delivered in 15 Days

Case #1: B2B SaaS Marketplace

Challenge: Connect freelancers and companies
Stack: Next.js + Supabase + Stripe
Features:

• Freelancer/company profiles
• Skills-based matching
• Integrated payments

Result: 150 signups in 2 weeks, 12 transactions

Case #2: AI Project Management Tool

Challenge: Generate roadmaps with AI
Stack: Next.js + OpenAI API + PostgreSQL
Features:

• Project brief import
• AI-generated roadmap
• PDF export

Result: €500 MRR after 1 month

Case #3: Healthcare Booking App

Challenge: Booking for practitioners
Stack: Next.js + MongoDB + Cal.com API
Features:

• Practitioner calendar
• Patient booking
• Email reminders

Result: 50 practitioners onboarded, 2K appointments/month

Mistakes to Avoid

🚫 Scope Creep

Symptom: "What if we also add..."
Consequence: 15 days → 2 months
Solution: List v2 features from the start

🚫 Technical Perfectionism

Symptom: "We need to refactor first..."
Consequence: Missed deadline
Solution: "Good enough" for MVP, clean up in v2

🚫 Overworked Design

Symptom: 50 landing page iterations
Consequence: Feature delays
Solution: Premium template + light adjustments

🚫 No User Testing

Symptom: "We’ll see at launch"
Consequence: Broken UX, high bounce rate
Solution: 5 user tests by Day 13

After the MVP: Growth

Weeks 1-4 Post-Launch

Goals:

• Collect feedback from 50 users
• Track metrics (signups, conversions, retention)
• Fix critical bugs

Months 2-3: Iteration

v2 Roadmap:

• Top 3 requested features
• UX optimizations based on analytics
• Third-party integrations if relevant

Months 4-6: Scaling

Focus:

• Performance and stability
• Process automation
• Prepare for fundraising if applicable

Ready to Launch Your MVP?

Pre-Launch Checklist

• Clearly defined problem
• 3 core features identified
• Budget validated
• 15 days available for follow-up
• 5 early adopters ready to test

My Commitments

✅ Delivery: Functional MVP in 15 calendar days
✅ Quality: Clean, documented, maintainable code
✅ Support: 1 month included post-launch
✅ Training: Handover for your future team
✅ Transparency: Weekly demos, Git access

Conclusion

The 15-day MVP is not a myth—it’s a proven methodology. The key: absolute focus on essentials, modern stack for speed, and experience to anticipate pitfalls.

Your idea deserves to be tested quickly. Don’t spend 6 months building something nobody wants.

Book a 30-minute call to discuss your project and see if the 15-day MVP format is right for you.

---

About the author: Jérémy Marquer is a freelance CTO specializing in rapid MVPs. He has delivered 20+ MVPs in under 3 weeks, 70% of which raised funds or reached profitability.