Nine years ago, I built two versions of Highlander: an original jQuery application and a React/Redux version that used the same backend concepts. After successfully reviving and deploying the jQuery version, I turned to Highlander-react-redux.
The goal was not simply to make an old repository run again. I wanted to improve the product, modernize its architecture without rewriting everything, and deploy something people could actually explore. This time, I used Turtle AI: a plan-driven engineering workflow built around Codex. It gave the AI explicit phases for planning, implementation, verification, testing, documentation, security review, and performance review.
The process worked—but it also taught me that more guardrails do not automatically create a more efficient workflow.
The Problem: More Than an Old React App
The application had the typical problems of a nine-year-old project:
