Hire a RAG and retrieval engineer on contract

Most wrong RAG answers are retrieval failures. I find where your assistant or agent loses the right context, fix it, and leave you with the evaluation to prove it.

Is this a fit?

A good fit if…

  • Your RAG assistant answers confidently, from the wrong document.
  • You switched to a bigger LLM and quality barely moved.
  • Your agent calls the right tools with the wrong context.
  • You can't say whether the last change to prompts, chunking or models helped.

Look elsewhere if…

  • You need a chatbot UI built. I work on retrieval and evaluation, not front ends.
  • You haven't chosen a use case yet. Start with a product decision; retrieval work needs real questions.
What you get

Deliverables your team keeps.

A retrieval test setReal user questions with the documents that should answer them, scored for retrieval and answers separately.
A failure diagnosisWhether answers go wrong in chunking, embeddings, the index, ranking or generation, measured per query.
Retrieval fixesStructure-aware chunking, hybrid search, metadata filters and a reranker, shipped and measured.
Evaluation you can trustLLM judges checked against human labels, running in CI so regressions get caught.
How it runs

From brief to handover.

Week 1

Collect real questions and failure cases. Map your pipeline from ingestion to answer.

Weeks 2–3

Build the test set and baseline. Trace each failing question to the stage that lost the answer.

Then

Fix retrieval in order of impact: hybrid search, query understanding, reranking, then chunking and embeddings.

Handover

An evaluation harness in your repository and documentation your team can keep using.

Stack

Works with what you run.

LangChain and LlamaIndex (or none)pgvectorPinecone, Weaviate, QdrantElasticsearch and OpenSearchEmbedding models and fine-tuningCross-encoder rerankersLLM-as-judge evaluationOpenAI, Anthropic and open modelsPython
Evidence

What I've built before.

Shopify SidekickWorked across the stack behind Shopify's AI assistant for merchants, mainly fine-tuning the LLMs that power it.
Vantage Discovery → ShopifyLed the ML team on an LLM-powered search engine through the acquisition, then worked on Shopify's new search engine.
PinterestSearch quality tech lead.
Shopify Foundation ModelsTrained commerce foundation models: domain-adaptive pre-training, SFT and DPO.
WritingWhy embeddings don't work for your search: the 7 failure modes I see most, with data. Read it →
Pricing and terms

How it's priced.

Contract engineeringStarting at $200/hourUp to 20 hours a week, hands-on in your codebase. Billed monthly.
AdvisoryStarting at $3,500/monthTwo working sessions a month, design and experiment reviews, and async questions.

Not sure where to start? Most teams begin with a fixed-scope search relevance audit.

Starting prices; the final quote depends on scope and follows a free intro call.

Remote, working with teams in the US, UK and Europe. Async-first, with live time during your Pacific mornings, or your morning and early afternoon if you're in Europe. Contracted and invoiced in USD through Infersense Labs LLC (Wyoming, USA).

FAQ

Questions buyers ask.

Do you work on AI agents, or just RAG?

Both. Agents depend on the same retrieval quality as RAG, plus tool use. At Shopify I worked across the stack behind Sidekick, its AI assistant for merchants, mainly fine-tuning the LLMs that power it.

Should we fine-tune instead?

Usually not first. If the right documents never reach the model, fine-tuning bakes the problem in. I measure retrieval first and recommend training only when the evaluation shows a gap it can close.

Which vector database should we use?

It matters less than the retrieval design around it. I usually work with what you already run.

How long until we see improvement?

The diagnosis in the first weeks usually points to fixes that move the metrics quickly, often hybrid search or query understanding, before any model work.

Free 30-minute intro call

Tell me what you're hiring for.

A free 30-minute call with me. You'll leave with a clear next step, and an honest answer on whether I'm the right person for it.