🐞 ladybug
ladybug is a visual debugger for Ruby web applications that uses the excellent Chrome Dev Tools as a user interface. It aims to provide a rich web backend debugging experience in a UI that many people are already familiar with for debugging their frontend Javascript.
To implement Ladybug, I wrote a custom debugger for Ruby that uses the Ruby Tracepoint API to hook into the code execution, and communicates with the browser dev tools using the Devtools remote debugging protocol over Web Sockets.
It supports things like setting breakpoints, stepping through code, and inspecting state. DevTools is designed only for debugging Javascript so not everything translates perfectly to Ruby, but I did my best to map the concepts.