Field notes — essays & research notes

Things I've written down.

Ruby, Rails, performance, security and applied machine learning. Updated when something feels finished.

All Ruby & Rails Security LLM & Agents MLOps Computer Vision Big Data Research
3 posts in LLM & Agents
LLM & AGENTS 08 / 15 / 26

pgvector or a dedicated vector database?

For most applications the answer is the database you already run, and the threshold where that stops being true is higher than the marketing suggests.

3 min
LLM & AGENTS 06 / 27 / 26

Chunking is a retrieval decision, not preprocessing

How you split documents determines what is findable. Everything downstream inherits that choice, and almost nobody measures it.

3 min
LLM & AGENTS 02 / 09 / 26

Your RAG chatbot doesn't have a model problem

It has a measurement problem. Why swapping the model is the last thing to try, what to instrument first, and how an aggregate score hides the failure that matters.

4 min