Migrating application settings to guix-home is something we want to make really approachable. Right now it's a relatively new and little-known feature but it could quickly become one of the top use cases for Guix, as a lot of people are interested in declarative application configuration.
A free software project to look at for ideas is Mackup: https://github.com/lra/mackup Its strategy is unsophisticated: it moves your configuration files to a synchronized directory in Dropbox (or similar) and replaces it with a symlink. But it's got a great migration story: you run `mackup backup' and it scans for config files for hundreds of applications [1] and automatically migrates them. Whether or not we would want the exact same experience, the overall vision of a single migration command that scans for dotfiles and adds them to your guix home is something we can aspire to. [1]: https://github.com/lra/mackup/tree/master/mackup/applications
