Activity is a starting point.
A workflow running for longer doesn’t mean it did more useful work. Before counting tasks, I want to know what a good result looks like and how someone checks it.
Notes on measurement →$~:whoami> matheo
I’m Matheo, a security engineer working across data platforms and applied AI. I turn fragmented information into useful software, with clear checks on what gets trusted, automated, and shipped.
A little curiosity goes a long way. Press ~ for a terminal.
$~:ls work/
Products and tools I’ve built: the problem, the stack, the decisions, and the evidence. Project identities stay private; the engineering is here to examine.
Data platforms & applied AI
Keeping searchable records, calculated answers, and generated explanations consistent as the underlying facts change.
Product engineering & information quality
Turning a stream of incoming information into searchable records and reviewed briefings, with usable behavior when dependencies fail.
Operational tooling & measurement
Collecting usage and cost without confusing missing data, observed activity, and estimates of value.
Real-time application engineering
Keeping a shared session coherent across phones, reconnects, timed phases, and external-service failures.
Browser product engineering
Giving multiple learning activities a consistent shell, shared preferences, and progress that stays on the device.
$~:cat principles
Tools change. Clear thinking, useful constraints, and honest verification keep earning their place.
Understand the people, constraints, and useful outcome before choosing a tool.
Make facts and calculations traceable, and leave uncertainty visible.
Give implementation and review distinct roles. Observe the result where people use it.
Automate bounded work, make tradeoffs explicit, and keep human judgment where it matters.
Illustrative workflow patterns, not a live team roster or the architecture of a particular product.
Matheo
Frames the problem · reviews consequential decisions
Make the input understandable before asking a model to interpret it.
Checks whether the available material supports the question.
Type: CheckerOrganizes inputs and flags gaps for review.
Type: AutomationUse generated language where it helps and explicit rules where precision matters.
Checks the result against the evidence and the task.
Type: CheckerProposes an explanation using the material provided.
Type: AIProduces numeric results from explicit inputs and rules.
Type: DeterministicKeep implementation and review separate, then observe the result.
Assesses the change against its stated goal and constraints.
Type: CheckerMakes a bounded change with clear acceptance criteria.
Type: AIExercises the change and makes failures visible.
Type: Automation$~:ls notes/
Security, software, product decisions, and whatever else I’m figuring out.
A workflow running for longer doesn’t mean it did more useful work. Before counting tasks, I want to know what a good result looks like and how someone checks it.
Notes on measurement →A small tool can keep preferences on the device, work without an account, and leave fewer things to maintain. Choosing what a product doesn’t need is part of the engineering.
More on the blog ↗$~:cat about
Security is my starting point. I’m interested in how data, software, and AI fit together—and in making the result useful to the people who rely on it.
World explorer, mentor, and tinkerer. Pushing to prod since Win95. I make room for community work, playful experiments, and learning something outside my usual lane.
More about my background ↗$~:ls community/
Helping older adults recognize scams, protect themselves online, and know where to turn when something goes wrong.
Community & resources$~:ls playground/
Games, desk accessories, and a terminal with a few secrets. All inside a little computer from a different era.
Enter Arcade 95