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RAG App Development

AI that answers from
your data, not its imagination.

RAG, retrieval-augmented generation, is how you make an AI answer from your real data instead of guessing. It retrieves the relevant facts first, then generates from them. That grounding is what separates a useful AI product from a confident liar, and it is the part competitors cannot copy. We build it on Claude, owned by you.

01
Retrieval
The system finds the relevant facts in your data.
02
Grounding
The model answers from those facts, not its memory.
03
Accuracy
Fewer hallucinations, answers you can trust.
04
Defensibility
Your data is the moat a model alone cannot give.
05
Built on Claude
Production retrieval and stack, owned by you.

What RAG is

Retrieve first.
Then answer.

A raw language model answers from its training, which means it guesses about anything specific to you and sometimes guesses wrong with total confidence. RAG fixes that: before answering, the system retrieves the relevant pieces of your real data, and the model answers from those. Grounded, accurate, and specific to your business.

01Why it matters
02The moat
03The build

Why it matters

Grounding is the difference between useful and dangerous

A language model on its own is a confident guesser. Ask it about your product, your data, your specifics, and it will answer fluently whether or not it actually knows, which means it will sometimes be wrong in a way that looks exactly like being right. For a real product, that is not a quirk, it is a liability. RAG is the fix.

Retrieval-augmented generation grounds the model in reality. Before the model answers, the system retrieves the relevant pieces of your actual data, your listings, your documents, your records, and the model answers from those, not from its hazy training memory. The result is an AI that is accurate about your business specifically, because it is reading your facts at the moment it answers.

We built exactly this in sellyourboat.io, our own venture. The Claude-powered buyer assistant helps people find the right boat by answering from the real listing data, over 12,000 live listings, not by guessing about boats in general. That is RAG doing its job: turning a generic model into something accurate and useful about a specific, real dataset.

The moat

Why RAG is where AI products get defensible

Here is the strategic point most founders miss: the model is a commodity, but your data is not. Anyone can call the same model you can. What they cannot copy is the retrieval over your proprietary data, the documents, records, and knowledge that only your business has. RAG is how that data becomes the product's competitive advantage rather than just sitting in a database.

This is why RAG is so often the right architecture for a defensible AI product. It puts your unique data at the centre of what the AI does, so the value comes from something a competitor cannot replicate by calling the same API. The better your retrieval over your data, the more useful and the more defensible the product, and that gap compounds as your data grows.

So we treat RAG not just as a technical pattern but as a positioning decision. Building the retrieval well, choosing what data to ground in, how to chunk and index it, how to keep it current, is building the moat. It is the part of an AI product most worth getting right, because it is the part that is genuinely yours.

The build

What building a real RAG system involves

Good RAG is less about the model and more about the retrieval, and the retrieval is where the craft is. The data has to be prepared, split into the right pieces, indexed so the relevant ones can be found fast, and kept current as it changes. Poor retrieval, fetching the wrong context, feeds the model bad facts, and a model grounded in bad facts is confidently wrong, the worst outcome.

Then there is the generation side, prompting the model to answer strictly from the retrieved facts and to say when it does not know, rather than filling gaps with invention. And evaluation, because RAG quality is not obvious from a demo, it shows up against real, varied questions, so you need a way to measure whether the answers are actually grounded and right.

We build all of this as production software, on Claude, on a real stack, owned by you, in eight weeks. We have done it in a live product with a large, changing dataset and real users depending on the answers, which is a different bar from a proof of concept over a handful of documents. RAG that holds up in production is the thing we build.

FAQ

Questions, answered straight.

What is RAG app development?

Building an AI app that uses retrieval-augmented generation: before answering, the system retrieves the relevant pieces of your real data, and the model answers from those rather than from its training. It grounds the AI in your facts, which makes it accurate about your business and defensible against competitors.

Why does RAG matter?

Because a raw model guesses about anything specific to you and sometimes guesses confidently wrong, a real liability in a product. RAG grounds the model in your actual data so it answers accurately about your business. It is the difference between a useful AI product and a fluent liar.

How is RAG a competitive moat?

The model is a commodity, anyone can call it. Your proprietary data is not. RAG puts retrieval over your unique data at the centre of the product, so the value comes from something competitors cannot copy by calling the same API. Better retrieval over your data means a more useful and more defensible product.

Have you built a RAG system in production?

Yes. The Claude-powered buyer assistant in sellyourboat.io, our own venture, answers from over 12,000 live listings to help people find the right boat, rather than guessing about boats in general. That is RAG holding up in a live product with a large, changing dataset and real users, a higher bar than a proof of concept.

What does a RAG app cost to build?

From 16,000 GBP for a focused RAG build, 30,000 GBP for a larger one with multiple data sources, user types, and integrations. Both fixed price, both eight weeks. The per-call inference cost is passed through at cost, and good retrieval design helps keep it down by having the model read less.

What makes RAG hard to build well?

The retrieval, not the model. The data has to be prepared, chunked, indexed, and kept current, and fetching the wrong context feeds the model bad facts. Plus prompting it to answer only from retrieved facts, and evaluating quality against real varied questions rather than a flattering demo. Production-grade RAG is a craft.

Ready

Ground your AI
in your data.

Tell us the data you want your AI to answer from. We will build the retrieval and the product around it, on Claude, owned by you, in eight weeks.

Book a scoping call →

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