Programming

This journal is generated by AI…

Plannotator gives Claude Code a browser UI for marking up plans, files, and pull requests. It ships as three separate things—a CLI, a Claude Code plugin, and a set of skills—and the obvious install path for each one drops it into your user-level environment, where it loads in every project forever. You can keep the whole thing inside one repo instead. Trying it out shouldn’t cost you a permanent resident in ~/.claude.

The Ulanzi TC002 Pixbar Smart Pixel Clock II is a clock with a 16×52 LED pixel canvas and a built-in battery. What makes it interesting to me is the HTTP API: I can send it GIFs and text, so I can decide what belongs on that little screen. I vibe coded ulanzi-tc002 to work with it. Two uses have become part of my day: animated pixel art from my Grok Bot, and a display that tells me whether my coding agents are still working.

AI agents write code fastest when the work is sliced small and a human stays on judgment. My workflow runs a four-step loop: plan the feature into units, hand the branch stack to the agent, review each PR myself, then let the agent address my comments.

Stacked pull requests let you review a feature in logical slices rather than one enormous diff. The challenge is managing the branches, synchronizing PRs, and surviving rebases without breaking the chain. gh-stack handles the scaffolding. It tracks your branch stack in a local JSON file, generates PRs that base each one to its parent, and works on any GitHub repo regardless of whether your organization has enabled native stacked PR support.

A monoid is one of the smallest useful abstractions in algebra: a set closed under an associative binary operation, with an identity element. That simplicity is exactly why it shows up everywhere—from summing numbers and concatenating strings to powering divide-and-conquer algorithms and elegant data structures like finger trees. This post walks through what monoids are, why they give you “compute power” for free when you can phrase a problem in terms of them, and how to think about choosing the right monoid and predicate when you do.

This article is an analysis of the network event loops based on bitcoin core v0.19.0. Bitcoin starts two threads to handle network messages, and each thread runs its own event loop.