Fine-tuning & RAG
Production LLM work across finance and developer tools
Two and a half years of shipping adaptation and retrieval systems for paying clients: fine-tuned LLMs for code generation and intent recognition, and RAG pipelines over financial documents.
- Where
- Fiverr — freelance
- When
- 2024 — present
- Role
- Machine Learning Engineer & Gen AI Specialist
- Stack
- PyTorch · GPT · BERT · FAISS · Pinecone · Transfer learning · Prompt engineering
Problem
Client work has a constraint research does not: someone is paying, and they will not accept a demo. Both engagements here started with a general-purpose model that was directionally right and practically unusable — a code assistant that misread intent, and a financial workflow where a human still re-read every document to find four numbers.
Constraints
- 01Fixed freelance budgets — no room for a training run that might not work
- 02Client data, client infrastructure, client compliance rules
- 03Handover matters: the client has to be able to run it after the engagement ends
- 04Measurable against the manual process it replaces, not against a benchmark
Architecture
Key decisions & trade-offs
Transfer learning before anything more ambitious
Fine-tuning from a strong base with transfer learning is the highest-certainty use of a fixed freelance budget. It gets to a measurable improvement fast, and it leaves room in the budget to iterate if the first attempt lands short.
Trade-offIt caps the ceiling — you inherit whatever the base model is bad at. For a client who needs a working system this quarter, a reliable 30% beats a speculative 60%.
FAISS and Pinecone, chosen per engagement
Where data could not leave the client's environment, FAISS ran locally. Where the client wanted no infrastructure to operate after handover, Pinecone was the honest answer. The retrieval logic stayed the same either way.
Trade-offSupporting both means an abstraction layer and two sets of operational quirks. It is the price of not forcing every client into the same deployment story.
Measure against the manual process, not a benchmark
The number a client cares about is how much work disappeared. Framing the financial pipeline as 40% less manual effort — rather than a retrieval score — is what made the value legible to the person approving the invoice.
Trade-offIt makes results harder to compare across engagements, and it means baselining the human process first. It is also the only number anyone acts on.