Posts on Dustin Lee

Why Maths for Machine Learning?

Tue, 24 Mar 2026 15:00:00 +0000

Part 1 of the Maths for ML series. What mathematics you actually need, why it matters, and a roadmap for learning it from first principles.

Regression and Decision Boundaries

Tue, 24 Mar 2026 14:00:00 +0000

Part 5 of the ML Fundamentals series. Linear and polynomial regression, Ridge and Lasso regularisation, logistic regression, the Perceptron, and visualising decision boundaries — all with infrastructure examples.

Classification — KNN, Naive Bayes, Decision Trees

Tue, 24 Mar 2026 13:00:00 +0000

Part 4 of the ML Fundamentals series. Three foundational classification algorithms — how they work, when to use each, and hands-on implementation with scikit-learn using infrastructure examples.

Python ML Toolkit

Tue, 24 Mar 2026 12:00:00 +0000

Part 3 of the ML Fundamentals series. Setting up a Python ML environment, and practical workflow patterns with Pandas, NumPy, Matplotlib, Scikit-learn, and TensorFlow.

Data Pre-processing and Evaluation

Tue, 24 Mar 2026 11:00:00 +0000

Part 2 of the ML Fundamentals series. Cleaning messy data, selecting features, splitting datasets, and measuring whether your model is actually any good.

What Is Machine Learning?

Tue, 24 Mar 2026 10:00:00 +0000

Part 1 of the ML Fundamentals series. What machine learning actually is, the three main learning paradigms, and why it matters for infrastructure, automation, and ops.

Managing a NixOS Fleet with Claude Code

Mon, 16 Mar 2026 10:00:00 +0000

Using Claude Code as an infrastructure co-pilot: a dedicated service account, scoped sudo, and a workflow for managing NixOS hosts through conversation.

Managing NixOS with Git: A Declarative Infrastructure Workflow

Thu, 05 Mar 2026 04:35:45 +0000

NixOS is unlike any other Linux distribution. Your entire system — packages, services, users, firewall rules, filesystems — is described in configuration files. Change a file, rebuild, and your system matches exactly what you declared. Pair this with Git, and you get version-controlled infrastructure that you can roll back, branch, diff, and share across machines.

This post walks through how a multi-host NixOS setup fits together, how Git integrates into the workflow, and how to use both effectively.

Building Gatehouse: A REST API for OpenBSD's PF Firewall

Mon, 23 Feb 2026 16:50:00 +1000

Managing PF through SSH doesn’t scale when you want phone toggles, family controls, and audit trails. Gatehouse wraps pfctl in 66 authenticated REST endpoints — from feature toggles and device blocking to pflog analytics and cron management.

Archiving Claude Code Conversations to Hugo

Thu, 19 Feb 2026 00:00:00 +0000

Every Claude Code session is a JSONL file sitting in ~/.claude/projects/. Across 17 projects I had 156 sessions — debugging logs, architecture decisions, implementation plans — all invisible unless you go digging through raw JSON. So I built a Python script that batch-converts them into browsable Hugo content, grouped by project.

Shortcode & Theme Showcase

Thu, 19 Feb 2026 00:00:00 +1100

Callout Shortcode

Three variants: alert, warning, and tip.

Alert

Alert callout — Use this for important information that demands attention. This is the default type if none is specified.

Warning

Warning callout — Use this for cautionary notes. Something might break if you ignore this.

Tip

Tip callout — Use this for helpful suggestions. For example: run make help to see all available targets.

Note Shortcode

Three variants: editor, update, and discussion. Each accepts an optional date parameter.

Makefiles as Your Project Interface

Wed, 18 Feb 2026 12:00:00 +1100

Every project gets a Makefile before it gets a README. Not as a build system, but as a project interface — coloured help menus, Docker Compose lifecycle, Terraform wrappers, and smart deploys across a dozen repos.

Documenting AI Conversations in Hugo

Wed, 18 Feb 2026 00:00:00 +0000

I find myself asking AI models questions constantly while working — debugging, architecture decisions, quick syntax lookups. Most of that knowledge disappears into chat history. So I built a Hugo shortcode to embed those conversations directly into blog posts.

GitLab Slash Commands for Claude Code

Wed, 18 Feb 2026 00:00:00 +0000

I’ve been using Claude Code as my daily driver for development work on a self-hosted GitLab instance. One of its best features is slash commands — custom prompts that you can invoke with /command from the CLI. I’ve built a set of GitLab-focused commands that have become muscle memory.

Here’s what I’m running and why they’ve been useful.