Ok, trying the new Claude Code, gave it a small edit to a real-life very large code base, also less common framework as it is Solid-js.
I wanted to move the video.js plugin registrations from the video player component (which cause them to be loaded repeatedly) to a top level component loaded once. It found the registrations, and created a utility function, and a component to add to the entry app.tsx.
I asked it if it wanted to know about clientOnly importing in Solid-js, and it responded yes. So, let it know about solid-js clientOnly() function for importing a client-only component and it did the correct changes for that as well.
There was a subtle issue in one of the plugins self registering, so when I provided this warning Claude went back and figured out why, and made a very safe correction (check if loaded, and load if not, just in case the plugin code changed). It also found another related issue of calling a method of a plugin, and added a safety check there.
Every step allows confirmation while viewing a diff in the terminal.
Using local history in WebStorm (any JetBrains IDE) allowed me to track through external changes as well using the IDE toolset, not just the terminal.
I am going to integrate it via MCP to manage local history, or to setup diffs so they are in the IDE more than only in the command-line. If you instruct it how you want to work with branches, or stash, it allows you to let it run amok with the safety of you doing merges in your favorite tool. More to come on this!