Free tools
Free, open-source
tools for builders.
The same tools I use in my own builds — for shaping specs, designing real apps, and running AI loops that ship.
Free to use or adapt.
No tool fits every build.
I’m Brian. These are some of my tools.
Every tool here was built for a specific job at a specific moment in time. That job may not be your job, and that moment may not be today.
So before you install anything (mine included), pause and think like a builder, not a fan:
- Does this fit the problem you’re actually solving?
- When was it built, and does the reason still hold?
- If it’s not a clean fit, can you adapt the idea without adopting the whole thing?
The goal isn’t to collect tools — it’s to get sharper at deciding which ones earn a place in your workflow. Use them as I do: starting points you adapt, not recipes you follow.
The toolbox.
All free. All open source. Take what fits.
PRD Creator
An agent skill to help you plan a new product's PRD and build-ready milestone prompts & tracking for your agent's build out.
Explore PRD CreatorDesign System
An agent skill that implements a robust, customizable design system in your app — sets up a preview & docs page and instructs your agents on how to adhere to it when building UI.
Explore Design SystemBuild New
A Rails-based starter template for kicking off new apps. Pre-wired with the patterns I reach for on every project, so you can skip the boilerplate and start building.
Explore Build NewBuild with Ralph
Coming soonMy spin on the Ralph Wiggum loop, with well-shaped specs baked into every turn. Keeps your agent grounded, on-task, and shipping real progress on each cycle.
Agent OS
Capture and apply your own coding standards across every agent build. A lightweight, language-agnostic system that helps your AI agents build the way you would.
Explore Agent OSDesign OS
Plan and design real apps using a system built for AI builders. Generates components, screens, and design specs that translate cleanly into code.
Explore Design OSStay in the loop
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