Build vs Buy a RAG system
Building a production RAG in-house is measured in months and needs a dedicated team; buying a managed platform is measured in weeks and a subscription. The choice mostly depends on your core business and your team.
Many teams underestimate the cost of taking a RAG to production: it's not the POC that costs, it's industrialization (retrieval quality, observability, scaling, compliance). Here's how to arbitrate between building and buying.
The real cost of building
A demo RAG takes a weekend; a production RAG takes months of continuous engineering: chunking, hybrid search, reranking, evaluation, observability, security, updates. The French government's RAG guide puts an integrator engagement around €100K over three months. Building in-house assumes a dedicated AI team.
When to buy, when to build
Buy if RAG isn't your product (agencies, firms, IT services delivering to clients): you save months and get predictable cost. Build if RAG IS your differentiator and you have an AI infrastructure team to maintain it.
Build vs Buy at a glance
Indicative orders of magnitude, June 2026.
| IgnitionRAG | Build (in-house) | |
|---|---|---|
| Time to first deployment | Weeks | Months |
| Cost | Solo subscription from €59/mo | Team + time (often tens to hundreds of K€) |
| Production-ready | Included (obs., reranking, eval) | Build and maintain it |
| GDPR / hosting | France, IA gérée par la plateforme, native governance | Implement it yourself |
| Maintenance | Handled by the platform | Continuous in-house team |
FAQ
How much does a custom RAG project cost?
Public estimates (including the French government's RAG guide) put an integrator engagement around €100K over three months, not counting maintenance. A managed platform is billed by subscription, from €59/mo.
When is it better to build yourself?
When RAG is your central product advantage and you have a dedicated AI infrastructure team to industrialize and maintain it over time.
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