Data & AI architect

Sam Reghenzi

Field notes on LLMs, agents, and the architecture that has to hold them.

Archive 12 posts
01 Sep 2026 blog

The Ontology Was Always a Bounded Context

Two agents meet in a park. "I've just had a complaint from a customer," says the first. "What's a customer?" asks the second. "Anyone with an account." A third agent walks over. "That's not a customer," it says. "A customer is anyone with an active subscription." The three agents pause …

30 Aug 2026 blog

The Guardrail Is Not in the Model

Frank Coyle gave a twenty-minute talk at the AI Engineer World's Fair that has been circulating for a few weeks now, and the argument in it is simple enough to state in one sentence: agentic systems need ontologies, because LLMs are probabilistic and probabilistic systems need logical...

26 Apr 2026 blog

Running Gemma 4 31B on an Apple Silicon Mac with Ollama

A practical configuration for a 32 GB M5 Mac that still needs to remain usable Running large language models locally has become surprisingly practical on Apple Silicon. With a modern Mac, Ollama, and a carefully quantized GGUF model, it is possible to run models that only a short time ago …

17 Apr 2020 blog

Forecasting Time Series from a COVID-19 Red Zone

Hello, dear citizen of the free world. I’m writing while I’m in a restricted lifestyle. On Monday night Italy’s prime minister decided that the entire country would be covered by restrictions that can be summarised as follows: “I stay at home” All travel was banned unless justified …

17 Apr 2017 blog

I will ride like a gentlemen

I will ride like a gentlemen On September 24th I will ride in the Distinguished Gentlemen Ride This is me an my bike at a recent Ducati Scrambler event As a rider of a stylish Ducati Scrambler, I will join my local chapter of the DGR. It is a retro-themed …