GitHub Copilot app adds stacked sessions and pull requests for linked coding tasks

The article chronicles a real modernization challenge that most developers face: maintaining legacy codebases with outdated dependencies. The author had attempted this work before using traditional methods and given up; the effort required to untangle React 15, Less, react-bootstrap, and years of accumulated cruft was simply not worth the time. The GitHub Copilot app changed that calculus by enabling iterative, scoped AI assistance rather than an all-or-nothing rewrite. The key insight the author describes is the problem of scope creep: when you don't have to write all the code yourself, it becomes tempting to balloon pull requests into 10,000-line monsters that tackle everything at once. By introducing stacked sessions and stacked pull requests, the tool let the author break the work into discrete, manageable chunks (frontend styles first, then the react-bootstrap replacement in a separate session), each building on the prior layer. The discovery of an old dev branch partway through also shows how messy real-world projects are—the AI assistant had to adapt on the fly, switching sessions rather than forcing the original plan. The author frames this as the future of developer experience, and the technical capability (ordering pull requests into a chain targeting one another) is now available in the GitHub Copilot app.