There has been a big change with Claude 4.0 in my opinion. Probably depends on your environment, but it’s the first time I’ve been able to get hundreds of lines of Python that just works when vibe coding a new project.

It’s still slower going as the codebase increases in size, and this is my hypothesis for the huge variance; I was getting giddy at how fast I blew through the first 5 hours of a small project (perhaps in 30 mins with Claude) but quickly lost velocity when I started implementing tests and editing existing code.