Westark Data

Field notes on data, Fabric, and applied AI.

I build data platforms on the Microsoft stack for a living. This is where I write down what works, what breaks, and what I would do differently.

John Morrison, senior data architect ยท Van Buren, Arkansas

John Morrison, smiling, in a blue checked button-down shirt, with forested mountain ridges and a sunset behind him.
John Morrison

What I write about

Notes from data projects in healthcare, retail, manufacturing, and finance.

  • 01Microsoft Fabric
  • 02Medallion architecture
  • 03Power BI
  • 04Python for dataflows
  • 05Applied AI
All the writing
Writing

Latest posts

Microsoft FabricJune 26, 2026
9 min read

You probably don't need Spark for that nightly batch

Spark on Fabric needs a capacity, and that capacity runs all day to serve your reports. For a nightly job on data that is not actually big, an Azure Container Apps job in Python bills per second and scales to zero. A cost comparison: capacity 24/7 vs pay-and-shut-off, OneLake vs ADLS, and when each wins.

Medallion ArchitectureJune 19, 2026
4 min read

The silver layer is staging, not clean bronze

The textbook says silver is a cleansed, queryable copy of bronze. Under real transformation complexity it almost never is. It becomes a staging area, or you sprout a fourth layer. An opinion piece on why medallion architecture is a metaphor, not a law, and how I actually use the silver layer.

Applied AIJune 12, 2026
5 min read

Karpathy's LLM Wiki versus a vector store: two ways to give an AI a memory

Andrej Karpathy's LLM Wiki has the agent compile knowledge into interlinked markdown pages. I run the opposite: atomic notes the agent searches by meaning. Same goal, opposite bet. An honest pros, cons, and which one wins for which job.

Applied AIJune 5, 2026
6 min read

How AI does the work on a data engagement, and the data it never touches

Useful AI on a consulting project is not a model pointed at your data lake. It is a model reading the ordinary materials of the work: a local copy of the repo, discovery and design transcripts, the statement of work and pre-sales handoff, the deliverables, and a private knowledge base that ties them together. Here is how they fit, and the line they all share: none of them is your production data.

Microsoft FabricMay 29, 2026
4 min read

Point your Fabric data agent at the semantic model, not the gold lakehouse

Fabric lets you attach a data agent to a lakehouse, a warehouse, or a Power BI semantic model. Most teams aim it straight at the gold layer. I think the semantic model is usually the better home, and the reasons go well past convenience.

More posts on the way. See every post

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Work with me

Talk shop, or hire the practice.

Westark Data LLC is my data consulting practice: Fabric platforms, pipelines, and the reporting on top of them.

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