You build the product with AI.
I make sure it is
solid
Your product is production-ready: the important parts work, people can sign up, pay, and use it without things breaking.
11+ years
shipping production software
2-4 weeks
to stabilize the core product
1 technical partner
who keeps things clear and practical
I've worked with
The gap
AI tools build features. But who builds the foundation?
Cursor, Bolt, and Claude Code can move fast. They do not give you a reliable product, a calm launch process, or a plan for when things get messy.
What changes
You should not have to learn DevOps just to ship your product.
My job is to turn your AI-built product into something that can handle real users, real growth, and real change without becoming chaos.
ARCHNo clear structure
The product grew quickly, but nobody defined how it should stay organized. Every new change adds more mess.
SAFENo safety net
There are no reliable checks before launch. Problems show up in front of customers instead of being caught early.
OPSNo reliable launch setup
The app is live, but there is no safe place to test, no clear alerts, and no fallback when something breaks.
CARENo maintenance plan
Small issues pile up quietly until they become expensive problems that slow everything down.
Process
Three steps from idea to production
The goal is simple: keep the speed of AI-assisted building without ending up with a product you are afraid to launch.
Discovery
I look at what you are building, where it feels fragile, and what needs to be fixed first. You leave with a clear plan.
Setup
I set up the parts behind the product that founders should not have to figure out alone, so launch feels safer and the product is easier to trust.
Build and maintain
You keep building features with AI. I keep the product healthy, answer the hard questions, and help when growth adds complexity.
Deliverables
Everything you need to ship. Nothing you do not.
This is not vague advice. You get the pieces that make an AI-built product feel stable, launchable, and easier to grow.
COREArchitecture that scales
A product setup that stays understandable as it grows instead of getting harder to work with every week.
- You and your AI tools work inside clear patterns
- New features create less cleanup later
- You know where things belong as the product evolves
AUTHSignups that work
The core user flows people expect are handled properly from the start.
- Login, signup, and password reset are in place
- Protected areas and sensible access rules are handled
- Less risk of fragile workarounds around user access
DATAData you can trust
Your product data has a clean foundation instead of a pile of shortcuts.
- The structure matches how your business actually works
- Changes can happen safely as the product grows
- Future updates are less scary and less brittle
SHIPSafer launches
Changes are checked before customers see them, not after something breaks.
- Problems are caught earlier instead of in production
- There is a better path from testing to going live
- Launch day comes with fewer surprises
WATCHVisibility and maintenance
You know when something goes wrong, and there is a plan to keep the product healthy.
- You hear about issues before they become customer complaints
- Updates and maintenance do not get ignored
- Less firefighting and fewer surprise problems over time
AIAI that keeps helping
Your tools stay useful because they are working inside a better system.
- Clear rules keep AI-generated work aligned
- Repeatable workflows make common tasks easier
- You move faster with less rework and less drift
Pricing
Choose your starting point
The scope changes with your product. The outcome stays the same: you get something you can launch and keep building without constant tech anxiety.
Maintenance retainer
OptionalStay healthy after launch.
Your first month on the Active plan is included with every Stack. After that, pick the level that fits.
Light
800 €/month
Async support, monitoring, and dependency updates. For founders who mostly build alone but want a safety net.
Get startedActive
1 500 €/month
Everything in Light, plus code reviews and a monthly check-in. For founders shipping fast who want hands-on guidance.
Get started
About
The foundation is the gap between prototype and product.
I help founders turn fast-moving AI-built products into products they can actually trust with real users.
For the last 11+ years, I have built the parts most customers never see but always feel when they are missing. For 5 years, I built my own SaaS products, in the restaurant industry and customer review management, and in 2023, I developed an AI orchestration technology for software development, well before these tools went mainstream.
I started Vibengineer because AI changed who gets to build software. Founders can move faster than ever, but the gap between a prototype and a real product is still very real. You stay in control of the idea and the features. I make sure the product underneath can support that speed.
— Sébastien
Expertise
Security partner

Antoine Heriaud
Certified pentester — Cybreach Consulting
Security scan available as an option inside my packages, so your product doesn't leak data or access.
Verified reviews
They've worked with me
Real feedback from clients and peers, verifiable on Trustpilot and LinkedIn.
“Sébastien is extremely efficient and rigorous. The project was led with great clarity and excellent structure. The work delivered is of very high quality. I will work with him again without hesitation on my next projects.”
Jon Mandel
Doxa Formation, training organisation
“I had the chance to work with Sébastien on a React/Next.js application, and everything went extremely well. Available, friendly and skilled, Sébastien has all the qualities to help you out!”
Sébastien Fieloux
Freelance Ruby on Rails / Magento 2
“Sébastien is experienced, very curious and a great listener. His feedback as a freelance also helped me approach projects differently. I really enjoyed working alongside him and recommend him without hesitation.”
Ariane Spanneut
Full Stack Engineer, ex-Coding Factory Squad
Blog
Ship Your AI-Built Product With Confidence
No jargon, no fluff. Just what you need to know to go from prototype to production.
Ready to launch
Stop worrying about the tech. Start shipping your product.
Book a free 30-minute discovery call. I will assess your current setup, show you the main risks, and recommend the right stack for your stage. No obligation.
Your idea stays confidential. Always.



